ORGANOMETALLIC COMPOUND AND LIGHT-EMITTING DEVICE INCLUDING ORGANOMETALLIC COMPOUND

Abstract

Provided are an organometallic compound represented by Formula 1, a light-emitting device including the organometallic compound represented by Formula 1, and an electronic apparatus including the light-emitting device:

##STR00001##

Formula 1 is understood by referring to the description of Formula 1 provided herein.

Claims

1. A light-emitting device comprising: a first electrode; a second electrode facing the first electrode; an interlayer disposed between the first electrode and the second electrode and comprising an emission layer; and an organometallic compound represented by Formula 1: ##STR00202## wherein in Formula 1, M is platinum (Pt), palladium (Pd), nickel (Ni), copper (Cu), silver (Ag), gold (Au), rhodium (Rh), iridium (Ir), ruthenium (Ru), osmium (Os), titanium (Ti), zirconium (Zr), hafnium (Hf), europium (Eu), terbium (Tb), or thulium (Tm), X.sub.1 to X.sub.4 are each independently carbon (C) or nitrogen (N), Y.sub.1 is N, A.sub.1 to A.sub.4 are each independently a C.sub.3-C.sub.60 carbocyclic group or a C.sub.1-C.sub.60 heterocyclic group, CY.sub.1 is a C.sub.1-C.sub.60 heterocyclic group, T.sub.1 is N, B, P, C(Z.sub.11), Si(Z.sub.11), or Ge(Z.sub.11), T.sub.2 to T.sub.4 are each independently a single bond, a double bond, *—N(Z.sub.21)—*′, *—B(Z.sub.21)—*′, *—P(Z.sub.21)—*′, *—C(Z.sub.21)(Z.sub.22)—*′, *—Si(Z.sub.21)(Z.sub.22)—*′, *—Ge(Z.sub.21)(Z.sub.22)—*′, *—S—*′, *—Se—*′, *—O—*, *—C(═O)—*′, *—S(═O)—*′, *—S(═O).sub.2—*′, *—C(Z.sub.21)=*′, *═C(Z.sub.21)—*′, *—C(Z.sub.21)═C(Z.sub.22)—*′, *—C(═S)—*′, or *—C≡C—*′, and * and *′ each indicate a binding site to an adjacent atom, a2 to a4 are each independently an integer from 0 to 3, R.sub.1 to R.sub.5, Z.sub.11, Z.sub.21, and Z.sub.22 are each independently hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, a C.sub.1-C.sub.60 alkyl group unsubstituted or substituted with at least one R.sub.10a, a C.sub.2-C.sub.60 alkenyl group unsubstituted or substituted with at least one R.sub.10a, a C.sub.2-C.sub.60 alkynyl group unsubstituted or substituted with at least one R.sub.10a, a C.sub.1-C.sub.60 alkoxy group unsubstituted or substituted with at least one R.sub.10a, a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a, a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a, a C.sub.6-C.sub.60 aryloxy group unsubstituted or substituted with at least one R.sub.10a, a C.sub.6-C.sub.60 arylthio group unsubstituted or substituted with at least one R.sub.10a, —Si(Q.sub.1)(Q.sub.2)(Q.sub.3), —N(Q.sub.1)(Q.sub.2), —B(Q.sub.1)(Q.sub.2), —C(═O)(Q.sub.1), —S(═O).sub.2(Q.sub.1), or —P(═O)(Q.sub.1)(Q.sub.2), b1 to b5 are each independently an integer from 0 to 10, two R.sub.1(s) of at least two R.sub.1(s) when b1 is 2 or greater are optionally bound to each other to form a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a, two R.sub.2(s) of at least two R.sub.2(s) when b2 is 2 or greater are optionally bound to each other to form a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a, two R.sub.3(s) of at least two R.sub.3(s) when b3 is 2 or greater are optionally bound to each other to form a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a, two R.sub.4(s) of at least two R.sub.4(s) when b4 is 2 or greater are optionally bound to each other to form a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a, two R.sub.5(s) of at least two R.sub.5(s) when b5 is 2 or greater are optionally bound to each other to form a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a, and R.sub.10a is: deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, or a nitro group; a C.sub.1-C.sub.60 alkyl group, a C.sub.2-C.sub.60 alkenyl group, a C.sub.2-C.sub.60 alkynyl group, or a C.sub.1-C.sub.60 alkoxy group, each unsubstituted or substituted with deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, a C.sub.3-C.sub.60 carbocyclic group, a C.sub.1-C.sub.60 heterocyclic group, a C.sub.6-C.sub.60 aryloxy group, a C.sub.6-C.sub.60 arylthio group, —Si(Q.sub.11)(Q.sub.12)(Q.sub.13), —N(Q.sub.11)(Q.sub.12), —B(Q.sub.11)(Q.sub.12), —C(═O)(Q.sub.11), —S(═O).sub.2(Q.sub.11), —P(═O)(Q.sub.11)(Q.sub.12), or a combination thereof; a C.sub.3-C.sub.60 carbocyclic group, a C.sub.1-C.sub.60 heterocyclic group, a C.sub.6-C.sub.60 aryloxy group, or a C.sub.6-C.sub.60 arylthio group, each unsubstituted or substituted with deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, a C.sub.1-C.sub.60 alkyl group, a C.sub.2-C.sub.60 alkenyl group, a C.sub.2-C.sub.60 alkynyl group, a C.sub.1-C.sub.60 alkoxy group, a C.sub.3-C.sub.60 carbocyclic group, a C.sub.1-C.sub.60 heterocyclic group, a C.sub.6-C.sub.60 aryloxy group, a C.sub.6-C.sub.60 arylthio group, —Si(Q.sub.21)(Q.sub.22)(Q.sub.23), —N(Q.sub.21)(Q.sub.22), —B(Q.sub.21)(Q.sub.22), —C(═O)(Q.sub.21), —S(═O).sub.2(Q.sub.21), —P(═O)(Q.sub.21)(Q.sub.22), or a combination thereof; or —Si(Q.sub.31)(Q.sub.32)(Q.sub.33), —N(Q.sub.31)(Q.sub.32), —B(Q.sub.31)(Q.sub.32), —C(═O)(Q.sub.31), —S(═O).sub.2(Q.sub.31), or —P(═O)(Q.sub.31)(Q.sub.32), wherein Q.sub.1 to Q.sub.3, Q.sub.11 to Q.sub.13, Q.sub.21 to Q.sub.23, and Q.sub.31 to Q.sub.33 are each independently: hydrogen; deuterium; —F; —Cl; —Br; —I; a hydroxyl group; a cyano group; a nitro group; a C.sub.1-C.sub.60 alkyl group; a C.sub.2-C.sub.60 alkenyl group; a C.sub.2-C.sub.60 alkynyl group; a C.sub.1-C.sub.60 alkoxy group; or a C.sub.3-C.sub.60 carbocyclic group or a C.sub.1-C.sub.60 heterocyclic group, each unsubstituted or substituted with deuterium, —F, a cyano group, a C.sub.1-C.sub.60 alkyl group, a C.sub.1-C.sub.60 alkoxy group, a phenyl group, a biphenyl group, or a combination thereof, and * and *′ each indicate a binding site to an adjacent atom.

2. The light-emitting device of claim 1, wherein the interlayer comprises: a first compound that is the organometallic compound represented by Formula 1; and a second compound comprising at least one π electron-deficient nitrogen-containing C.sub.1-C.sub.60 cyclic group, a third compound comprising a group represented by Formula 3, a fourth compound capable of emitting delayed fluorescence, or a combination thereof, and the first compound, the second compound, the third compound, and the fourth compound are different from one another: ##STR00203## wherein in Formula 3, ring CY.sub.71 and ring CY72 are each independently a π electron-rich C.sub.3-C.sub.60 cyclic group or a pyridine group, X.sub.71 is a single bond or a linking group comprising O, S, N, B, C, Si, or a combination thereof, * indicates a binding site to an adjacent atom in the third compound, and the following compounds are excluded from the third compound: ##STR00204##

3. The light-emitting device of claim 2, wherein the emission layer comprises: the first compound; and the second compound, the third compound, the fourth compound, or a combination thereof, and the emission layer emits phosphorescence or fluorescence emitted from the first compound.

4. The light-emitting device of claim 2, wherein the second compound comprises a pyridine group, a pyrimidine group, a pyrazine group, a pyridazine group, a triazine group, or a combination thereof.

5. The light-emitting device of claim 2, wherein the fourth compound is a compound comprising at least one cyclic group comprising boron (B) and nitrogen (N) as ring-forming atoms.

6. The light-emitting device of claim 2, wherein the second compound comprises a compound represented by Formula 2: ##STR00205## wherein in Formula 2, L.sub.61 to L.sub.63 are each independently a single bond, a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a, or a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a, b61 to b63 are each independently an integer from 1 to 5, X.sub.64 is N or C(R.sub.64), X.sub.65 is N or C(R.sub.65), X.sub.66 is N or C(R.sub.66), at least one of X.sub.64 to X.sub.66 is N, R.sub.61 to R.sub.66 are each independently hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, a C.sub.1-C.sub.60 alkyl group unsubstituted or substituted with at least one R.sub.10a, a C.sub.2-C.sub.60 alkenyl group unsubstituted or substituted with at least one R.sub.10a, a C.sub.2-C.sub.60 alkynyl group unsubstituted or substituted with at least one R.sub.10a, a C.sub.1-C.sub.60 alkoxy group unsubstituted or substituted with at least one R.sub.10a, a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a, a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a, a C.sub.6-C.sub.60 aryloxy group unsubstituted or substituted with at least one R.sub.10a, a C.sub.6-C.sub.60 arylthio group unsubstituted or substituted with at least one R.sub.10a, —C(Q.sub.1)(Q.sub.2)(Q.sub.3), —Si(Q.sub.1)(Q.sub.2)(Q.sub.3), —N(Q.sub.1)(Q.sub.2), —B(Q.sub.1)(Q.sub.2), —C(═O)(Q.sub.1), —S(═O).sub.2(Q.sub.1), or —P(═O)(Q.sub.1)(Q.sub.2), and R.sub.10a and Q.sub.1 to Q.sub.3 are respectively the same as described in connection with R.sub.10a and Q.sub.1 to Q.sub.3 in Formula 1.

7. The light-emitting device of claim 2, wherein at least one of Conditions 1 to 4 is satisfied: [Condition 1] LUMO energy level in electron volts (eV) of the third compound >LUMO energy level in electron volts (eV) of the first compound [Condition 2] LUMO energy level in electron volts (eV) of the first compound >LUMO energy level in electron volts (eV) of the second compound [Condition 3] HOMO energy level in electron volts (eV) of the first compound >HOMO energy level in electron volts (eV) of the third compound [Condition 4] HOMO energy level in electron volts (eV) of the third compound >HOMO energy level in electron volts (eV) of the second compound.

8. An electronic apparatus comprising: the light-emitting device of claim 1; and a thin-film transistor, wherein the thin-film transistor comprises a source electrode and a drain electrode, and the first electrode of the light-emitting device is electrically connected to at least one of the source electrode and the drain electrode of the thin-film transistor.

9. The electronic apparatus of claim 8, further comprising a color filter, a color-conversion layer, a touchscreen layer, a polarization layer, or a combination thereof.

10. An organometallic compound represented by Formula 1: ##STR00206## wherein in Formula 1, M is platinum (Pt), palladium (Pd), nickel (Ni), copper (Cu), silver (Ag), gold (Au), rhodium (Rh), iridium (Ir), ruthenium (Ru), osmium (Os), titanium (Ti), zirconium (Zr), hafnium (Hf), europium (Eu), terbium (Tb), or thulium (Tm), X.sub.1 to X.sub.4 are each independently carbon (C) or nitrogen (N), Y.sub.1 is N, A.sub.1 to A.sub.4 are each independently a C.sub.3-C.sub.60 carbocyclic group or a C.sub.1-C.sub.60 heterocyclic group, CY.sub.1 is a C.sub.1-C.sub.60 heterocyclic group, T.sub.1 is N, B, P, C(Z.sub.11), Si(Z.sub.11), or Ge(Z.sub.11), T.sub.2 to T.sub.4 are each independently a single bond, a double bond, *—N(Z.sub.21)—*′, *—B(Z.sub.21)—*′, *—P(Z.sub.21)—*′, *—C(Z.sub.21)(Z.sub.22)—*′, *—Si(Z.sub.21)(Z.sub.22)—*′, *—Ge(Z.sub.21)(Z.sub.22)—*′, *—S—*′, *—Se—*′, *—O—*, *—C(═O)—*′, *—S(═O)—*′, *—S(═O).sub.2—*′, *—C(Z.sub.21)=*′, *═C(Z.sub.21)—*′, *—C(Z.sub.21)═C(Z.sub.22)—*′, *—C(═S)—*′, or *—C≡C—*′, and * and *′ each indicate a binding site to an adjacent atom, a2 to a4 are each independently an integer from 0 to 3, R.sub.1 to R.sub.5, Z.sub.11, Z.sub.21, and Z.sub.22 are each independently hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, a C.sub.1-C.sub.60 alkyl group unsubstituted or substituted with at least one R.sub.10a, a C.sub.2-C.sub.60 alkenyl group unsubstituted or substituted with at least one R.sub.10a, a C.sub.2-C.sub.60 alkynyl group unsubstituted or substituted with at least one R.sub.10a, a C.sub.1-C.sub.60 alkoxy group unsubstituted or substituted with at least one R.sub.10a, a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a, a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a, a C.sub.6-C.sub.60 aryloxy group unsubstituted or substituted with at least one R.sub.10a, a C.sub.6-C.sub.60 arylthio group unsubstituted or substituted with at least one R.sub.10a, —Si(Q.sub.1)(Q.sub.2)(Q.sub.3), —N(Q.sub.1)(Q.sub.2), —B(Q.sub.1)(Q.sub.2), —C(═O)(Q.sub.1), —S(═O).sub.2(Q.sub.1), or —P(═O)(Q.sub.1)(Q.sub.2), b1 to b5 are each independently an integer from 0 to 10, two R.sub.1(s) of at least two R.sub.1(s) when b1 is 2 or greater are optionally bound to each other to form a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a, two R.sub.2(s) of at least two R.sub.2(s) when b2 is 2 or greater are optionally bound to each other to form a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a, two R.sub.3(s) of at least two R.sub.3(s) when b3 is 2 or greater are optionally bound to each other to form a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a, two R.sub.4(s) of at least two R.sub.4(s) when b4 is 2 or greater are optionally bound to each other to form a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a, two R.sub.5(s) of at least two R.sub.5(s) when b5 is 2 or greater are optionally bound to each other to form a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a, and R.sub.10a is: deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, or a nitro group; a C.sub.1-C.sub.60 alkyl group, a C.sub.2-C.sub.60 alkenyl group, a C.sub.2-C.sub.60 alkynyl group, or a C.sub.1-C.sub.60 alkoxy group, each unsubstituted or substituted with deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, a C.sub.3-C.sub.60 carbocyclic group, a C.sub.1-C.sub.60 heterocyclic group, a C.sub.6-C.sub.60 aryloxy group, a C.sub.6-C.sub.60 arylthio group, —Si(Q.sub.11)(Q.sub.12)(Q.sub.13), —N(Q.sub.11)(Q.sub.12), —B(Q.sub.11)(Q.sub.12), —C(═O)(Q.sub.11), —S(═O).sub.2(Q.sub.11), —P(═O)(Q.sub.11)(Q.sub.12), or a combination thereof; a C.sub.3-C.sub.60 carbocyclic group, a C.sub.1-C.sub.60 heterocyclic group, a C.sub.6-C.sub.60 aryloxy group, or a C.sub.6-C.sub.60 arylthio group, each unsubstituted or substituted with deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, a C.sub.1-C.sub.60 alkyl group, a C.sub.2-C.sub.60 alkenyl group, a C.sub.2-C.sub.60 alkynyl group, a C.sub.1-C.sub.60 alkoxy group, a C.sub.3-C.sub.60 carbocyclic group, a C.sub.1-C.sub.60 heterocyclic group, a C.sub.6-C.sub.60 aryloxy group, a C.sub.6-C.sub.60 arylthio group, —Si(Q.sub.21)(Q.sub.22)(Q.sub.23), —N(Q.sub.21)(Q.sub.22), —B(Q.sub.21)(Q.sub.22), —C(═O)(Q.sub.21), —S(═O).sub.2(Q.sub.21), —P(═O)(Q.sub.21)(Q.sub.22), or a combination thereof; or —Si(Q.sub.31)(Q.sub.32)(Q.sub.33), —N(Q.sub.31)(Q.sub.32), —B(Q.sub.31)(Q.sub.32), —C(═O)(Q.sub.31), —S(═O).sub.2(Q.sub.31), or —P(═O)(Q.sub.31)(Q.sub.32), wherein Q.sub.1 to Q.sub.3, Q.sub.11 to Q.sub.13, Q.sub.21 to Q.sub.23, and Q.sub.31 to Q.sub.33 are each independently: hydrogen; deuterium; —F; —Cl; —Br; —I; a hydroxyl group; a cyano group; a nitro group; a C.sub.1-C.sub.60 alkyl group; a C.sub.2-C.sub.60 alkenyl group; a C.sub.2-C.sub.60 alkynyl group; a C.sub.1-C.sub.60 alkoxy group; or a C.sub.3-C.sub.60 carbocyclic group or a C.sub.1-C.sub.60 heterocyclic group, each unsubstituted or substituted with deuterium, —F, a cyano group, a C.sub.1-C.sub.60 alkyl group, a C.sub.1-C.sub.60 alkoxy group, a phenyl group, a biphenyl group, or a combination thereof, and * and *′ each indicate a binding site to an adjacent atom.

11. The organometallic compound of claim 10, wherein a bond between X.sub.1 and M is a covalent bond, a bond between X.sub.2 and M is a covalent bond, a bond between X.sub.3 and M is a coordinate bond, and a bond between X.sub.4 and M is a covalent bond or a coordinate bond.

12. The organometallic compound of claim 10, wherein A.sub.3 is an X.sub.3-containing 5-membered ring or an X.sub.3-containing 5-membered ring to which at least one 6-membered ring is condensed, and A.sub.4 is an X.sub.4-containing 5-membered ring, an X.sub.4-containing 5-membered ring to which at least one 6-membered ring is condensed, or an X.sub.4-containing 6-membered ring.

13. The organometallic compound of claim 10, wherein a group represented by ##STR00207## in Formula 1 is a group represented by one of Formulae A1(1) to A1(32): ##STR00208## ##STR00209## ##STR00210## ##STR00211## ##STR00212## ##STR00213## ##STR00214## ##STR00215## wherein in Formulae A1(1) to A1(32), X.sub.1, T.sub.1, and Y.sub.1 are respectively the same as described in connection with X.sub.1, T.sub.1, and Y.sub.1 in Formula 1, R.sub.11 and R.sub.12 are each independently the same as described in connection with R.sub.1 in Formula 1, R.sub.51 and R.sub.52 are each independently the same as described in connection with R.sub.5 in Formula 1, b52 is an integer from 0 to 2, b53 is an integer from 0 to 3, b54 is an integer from 0 to 4, R.sub.11 and R.sub.12 are optionally bound to each other to form a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a, two R.sub.51(s) of at least two R.sub.51(s) when b53 is 2 or greater are optionally bound to each other to form a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a, two R.sub.51(s) when b52 is 2 are optionally bound to each other to form a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a, two R.sub.52(s) of at least two R.sub.52(s) when b54 is 2 or greater are optionally bound to each other to form a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a, two R.sub.52(s) of at least two R.sub.52(s) when b53 is 2 or greater are optionally bound to each other to form a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a, R.sub.10a is the same as described in connection with R.sub.10a in Formula 1, * indicates a binding site to M in Formula 1, *′ indicates a binding site to T.sub.4 in Formula 1, and *″ indicates a binding site to A.sub.2 in Formula 1.

14. The organometallic compound of claim 10, wherein a group represented by ##STR00216## in Formula 1 is a group represented by one of Formulae A2-1 to A2-8: ##STR00217## wherein in Formulae A2-1 to A2-8, X.sub.2 is the same as described in connection with X.sub.2 in Formula 1, X.sub.21 to X.sub.23 are each independently the same as described in connection with X.sub.2 in Formula 1, R.sub.21 to R.sub.23 are each independently the same as described in connection with R.sub.2 in Formula 1, and R.sub.21 to R.sub.23 are each not hydrogen, two of R.sub.21 to R.sub.23 are optionally bound to each other to form a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a, R.sub.10a is the same as described in connection with R.sub.10a in Formula 1, * indicates a binding site to M in Formula 1, *′ indicates a binding site to T.sub.2 in Formula 1, and *″ indicates a binding site to T.sub.1 in Formula 1.

15. The organometallic compound of claim 10, wherein a group represented by ##STR00218## in Formula 1 is a group represented by one of Formulae A3-1 to A3-15: ##STR00219## ##STR00220## wherein in Formulae A3-1 to A3-15, X.sub.3 is the same as described in connection with X.sub.3 in Formula 1, X.sub.32 to X.sub.37 are each independently the same as described in connection with X.sub.3 in Formula 1, R.sub.31 to R.sub.34 are each independently the same as described in connection with R.sub.3 in Formula 1, and R.sub.31 to R.sub.33 are each not hydrogen, b34 is an integer from 0 to 4, two of R.sub.31 to R.sub.34 are optionally bound to each other to form a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a, two R.sub.34(s) of at least two R.sub.34(s) when b34 is 2 or greater are optionally bound to each other to form a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a, R.sub.10a is the same as described in connection with R.sub.10a in Formula 1, * indicates a binding site to M in Formula 1, *″ indicates a binding site to T.sub.2 in Formula 1, and *′ in Formulae A3-9 to A3-12 and A3-15 is a binding site to T.sub.3 in Formula 1.

16. The organometallic compound of claim 10, wherein a group represented by ##STR00221## in Formula 1 is a group represented by one of Formulae A4-1 to A4-32: ##STR00222## ##STR00223## ##STR00224## ##STR00225## ##STR00226## wherein in Formulae A4-1 to A4-32, X.sub.4 is the same as described in connection with X.sub.4 in Formula 1, X.sub.41 to X.sub.47 are each independently the same as described in connection with X.sub.4 in Formula 1, R.sub.41 to R.sub.45 are each independently the same as described in connection with R.sub.4 in Formula 1, and R.sub.41 to R.sub.43 are each not hydrogen, R.sub.44 in Formulae A4-20, A4-25, A4-26, and A4-28 to A4-30 is not hydrogen, b43 is an integer from 0 to 3, b44 is an integer from 0 to 4, two of R.sub.41 to R.sub.45 are optionally bound to each other to form a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a, two R.sub.44(s) of at least two R.sub.44(s) when b44 is 2 or greater are optionally bound to each other to form a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a, two R.sub.45(s) of at least two R.sub.45(s) when b43 is 2 or greater are optionally bound to each other to form a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a, R.sub.10a is the same as described in connection with R.sub.10a in Formula 1, * indicates a binding site to M in Formula 1, *″ indicates a binding site to T.sub.4 in Formula 1, and *′ in Formulae A4-9 to A4-12, A4-15, A4-31, and A4-32 is a binding site to T.sub.3 in Formula 1.

17. The organometallic compound of claim 10, wherein CY.sub.1 is a Y.sub.1-containing 5-membered ring, a Y.sub.1-containing 5-membered ring condensed to at least one 6-membered ring, or a Y.sub.1-containing 6-membered ring.

18. The organometallic compound of claim 10, wherein a group represented by ##STR00227## in Formula 1 is a group represented by Formula CY1(a): ##STR00228## wherein in Formula CY1(a), Y.sub.1a is C or N, CY.sub.11 is a C.sub.3-C.sub.60 carbocyclic group or a C.sub.1-C.sub.60 heterocyclic group, CY.sub.12 is the same as described in connection with CY.sub.1 in Formula 1, R.sub.5a and R.sub.5b are each independently the same as described in connection with R.sub.5 in Formula 1, b5a and b5b are each independently the same as described in connection with b5 in Formula 1, two R.sub.5a(s) of at least two R.sub.5a(s) when b5a is 2 or greater are optionally bound to each other to form a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a, two R.sub.5b(s) of at least two R.sub.5b(s) when b5b is 2 or greater are optionally bound to each other to form a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a, R.sub.10a is the same as described in connection with R.sub.10a in Formula 1, *′ indicates a binding site to A.sub.1 in Formula 1, and *″ indicates a binding site to T.sub.1 in Formula 1.

19. The organometallic compound of claim 10, wherein the organometallic compound is selected from Compounds 1 to 105: ##STR00229## ##STR00230## ##STR00231## ##STR00232## ##STR00233## ##STR00234## ##STR00235## ##STR00236## ##STR00237## ##STR00238## ##STR00239## ##STR00240## ##STR00241## ##STR00242## ##STR00243## ##STR00244## ##STR00245## ##STR00246## ##STR00247## ##STR00248## ##STR00249## ##STR00250## ##STR00251## ##STR00252## ##STR00253## ##STR00254## ##STR00255## ##STR00256## ##STR00257## ##STR00258## ##STR00259## ##STR00260## ##STR00261## ##STR00262## ##STR00263## ##STR00264## ##STR00265## ##STR00266## ##STR00267## ##STR00268## ##STR00269## ##STR00270##

20. The organometallic compound of claim 10, wherein the organometallic compound emits blue light having a maximum emission wavelength in a range of about 430 nanometers (nm) to about 490 nm.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0047] The above and other aspects and features of the disclosure will become more apparent by describing in detail embodiments thereof with reference to the accompanying drawings, in which:

[0048] FIG. 1 is a schematic cross-sectional view of a light-emitting device according to an embodiment;

[0049] FIG. 2 is a schematic cross-sectional view of an electronic apparatus according to an embodiment; and

[0050] FIG. 3 is a schematic cross-sectional view of an electronic apparatus according to an embodiment.

DETAILED DESCRIPTION OF THE EMBODIMENTS

[0051] The disclosure will now be described more fully hereinafter with reference to the accompanying drawings, in which embodiments are shown. This disclosure may, however, be embodied in different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art.

[0052] In the drawings, the sizes, thicknesses, ratios, and dimensions of the elements may be exaggerated for ease of description and for clarity. Like numbers refer to like elements throughout.

[0053] In the description, it will be understood that when an element (or region, layer, part, etc.) is referred to as being “on”, “connected to”, or “coupled to” another element, it can be directly on, connected to, or coupled to the other element, or one or more intervening elements may be present therebetween. In a similar sense, when an element (or region, layer, part, etc.) is described as “covering” another element, it can directly cover the other element, or one or more intervening elements may be present therebetween.

[0054] In the description, when an element is “directly on,” “directly connected to,” or “directly coupled to” another element, there are no intervening elements present. For example, “directly on” may mean that two layers or two elements are disposed without an additional element such as an adhesion element therebetween.

[0055] As used herein, the expressions used in the singular such as “a,” “an,” and “the,” are intended to include the plural forms as well, unless the context clearly indicates otherwise.

[0056] As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items. For example, “A and/or B” may be understood to mean “A, B, or A and B.” The terms “and” and “or” may be used in the conjunctive or disjunctive sense and may be understood to be equivalent to “and/or”.

[0057] In the specification and the claims, the term “at least one of” is intended to include the meaning of “at least one selected from the group of” for the purpose of its meaning and interpretation. For example, “at least one of A and B” may be understood to mean “A, B, or A and B.” When preceding a list of elements, the term, “at least one of,” modifies the entire list of elements and does not modify the individual elements of the list.

[0058] It will be understood that, although the terms first, second, etc. may be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another element. Thus, a first element could be termed a second element without departing from the teachings of the disclosure. Similarly, a second element could be termed a first element, without departing from the scope of the disclosure.

[0059] The spatially relative terms “below”, “beneath”, “lower”, “above”, “upper”, or the like, may be used herein for ease of description to describe the relations between one element or component and another element or component as illustrated in the drawings. It will be understood that the spatially relative terms are intended to encompass different orientations of the device in use or operation, in addition to the orientation depicted in the drawings. For example, in the case where a device illustrated in the drawing is turned over, the device positioned “below” or “beneath” another device may be placed “above” another device. Accordingly, the illustrative term “below” may include both the lower and upper positions. The device may also be oriented in other directions and thus the spatially relative terms may be interpreted differently depending on the orientations.

[0060] The terms “about” or “approximately” as used herein is inclusive of the stated value and means within an acceptable range of deviation for the recited value as determined by one of ordinary skill in the art, considering the measurement in question and the error associated with measurement of the recited quantity (i.e., the limitations of the measurement system). For example, “about” may mean within one or more standard deviations, or within +20%, +10%, or +5% of the stated value.

[0061] It should be understood that the terms “comprises,” “comprising,” “includes,” “including,” “have,” “having,” “contains,” “containing,” and the like are intended to specify the presence of stated features, integers, steps, operations, elements, components, or combinations thereof in the disclosure, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, or combinations thereof.

[0062] Unless otherwise defined or implied herein, all terms (including technical and scientific terms) used have the same meaning as commonly understood by those skilled in the art to which this disclosure pertains. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and should not be interpreted in an ideal or excessively formal sense unless clearly defined in the specification.

[0063] An organometallic compound may be represented by Formula 1:

##STR00008##

[0064] In Formula 1, M may be platinum (Pt), palladium (Pd), nickel (Ni), copper (Cu), silver (Ag), gold (Au), rhodium (Rh), iridium (Ir), ruthenium (Ru), osmium (Os), titanium (Ti), zirconium (Zr), hafnium (Hf), europium (Eu), terbium (Tb), or thulium (Tm).

[0065] In an embodiment, M in Formula 1 may be platinum (Pt), palladium (Pd), nickel (Ni), copper (Cu), silver (Ag), or gold (Au), but embodiments are not limited thereto.

[0066] In Formula 1, X.sub.1 to X.sub.4 may each independently be C or N.

[0067] In an embodiment, X.sub.1 to X.sub.4 may each be C, or X.sub.1 to X.sub.3 may each be C and X.sub.4 may be N.

[0068] In an embodiment, in Formula 1, a bond between X.sub.1 and M may be a covalent bond, a bond between X.sub.2 and M may be a covalent bond, a bond between X.sub.3 and M may be a coordinate bond, and a bond between X.sub.4 and M may be a covalent bond or a coordinate bond.

[0069] In embodiments, in Formula 1, a bond between X.sub.1 and M may be a covalent bond, and X.sub.1 may be C.

[0070] In embodiments, in Formula 1, a bond between X.sub.2 and M may be a covalent bond, and X.sub.2 may be C.

[0071] In embodiments, in Formula 1, a bond between X.sub.3 and M may be a coordinate bond, and X.sub.3 may be C.

[0072] In embodiments, in Formula 1, a bond between X.sub.4 and M may be a coordinate bond, and X.sub.4 may be C.

[0073] In embodiments, in Formula 1, a bond between X.sub.4 and M may be a covalent bond, and X.sub.4 may be N.

[0074] In Formula 1, Y.sub.1 may be N.

[0075] In Formula 1, A.sub.1 to A.sub.4 may each independently be a C.sub.3-C.sub.60 carbocyclic group or a C.sub.1-C.sub.60 heterocyclic group.

[0076] In an embodiment, in Formula 1, A.sub.1 may be an X.sub.1-containing 6-membered ring.

[0077] In an embodiment, in Formula 1, A.sub.2 may be an X.sub.2-containing 6-membered ring.

[0078] In an embodiment, in Formula 1, A.sub.3 may be an X.sub.3-containing 5-membered ring or an X.sub.3-containing 5-membered ring condensed with at least one 6-membered ring.

[0079] In an embodiment, in Formula 1, A.sub.4 may be an X.sub.4-containing 5-membered ring, an X.sub.4-containing 5-membered ring condensed with at least one 6-membered ring, or an X.sub.4-containing 6-membered ring.

[0080] In an embodiment, in Formula 1, A.sub.3 may be an X.sub.3-containing 5-membered ring or an X.sub.3-containing 5-membered ring condensed with at least one 6-membered ring, and A.sub.4 may be an X.sub.4-containing 5-membered ring, an X.sub.4-containing 5-membered ring condensed with at least one 6-membered ring, or an X.sub.4-containing 6-membered ring.

[0081] In an embodiment, the X.sub.1-containing 6-membered ring in A.sub.1, the X.sub.2-containing 6-membered ring in A.sub.2, and the X.sub.4-containing 6-membered ring in A.sub.4 may each independently be a benzene group, a pyridine group, or a pyrimidine group.

[0082] In an embodiment, the X.sub.3-containing 5-membered ring and the X.sub.3-containing 5-membered ring condensed with at least one 6-membered ring in A.sub.3 and the X.sub.4-containing 5-membered ring and the X.sub.4-containing 5-membered ring condensed with at least one 6-membered ring in A.sub.4 may each independently be a pyrrole group, a pyrazole group, an imidazole group, a triazole group, a furan group, an oxazole group, an isooxazole group, a thiazole group, an isothiazole group, an oxadiazole group, or a thiadiazole group.

[0083] In an embodiment, in Formula 1, a group represented by

##STR00009##

may be a group represented by one of Formulae A1(1) to A1(32):

##STR00010## ##STR00011## ##STR00012##

[0084] In Formulae A1(1) to A1(32),

[0085] X.sub.1, T.sub.1, and Y.sub.1 may respectively be the same as described in connection with X.sub.1, T.sub.1, and Y.sub.1 in Formula 1,

[0086] R.sub.11 and R.sub.12 may each independently be the same as described in connection with R.sub.1 in Formula 1,

[0087] R.sub.51 and R.sub.52 may each independently be the same as described in connection with R.sub.5 in Formula 1,

[0088] b52 may be an integer from 0 to 2,

[0089] b53 may be an integer from 0 to 3,

[0090] b54 may be an integer from 0 to 4,

[0091] Ru and R.sub.12 may optionally be bound to each other to form a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a, two R.sub.51(s) of at least two R.sub.51(s) when b53 is 2 or greater may optionally be bound to each other to form a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a, two R.sub.5i(s) when b52 is 2 may optionally be bound to each other to form a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a, two R.sub.52(s) of at least two R.sub.52(s) when b54 is 2 or greater may optionally be bound to each other to form a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a, two R.sub.52(s) of at least two R.sub.52(s) when b53 is 2 or greater may optionally be bound to each other to form a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a,

[0092] R.sub.10a may be the same as described in connection with R.sub.10a in Formula 1,

[0093] * indicates a binding site to M in Formula 1,

[0094] *′ indicates a binding site to T.sub.4 in Formula 1, and

[0095] *″ indicates a binding site to A.sub.2 in Formula 1.

[0096] In an embodiment, in Formula 1, a group represented by

##STR00013##

may be a group represented by one of Formulae A1-1 to A1-4:

##STR00014##

[0097] In Formulae A1-1 to A1-4,

[0098] X.sub.1 may be the same as described in connection with X.sub.1 in Formula 1,

[0099] X.sub.11 and X.sub.12 may each independently be the same as described in connection with X.sub.1 in Formula 1,

[0100] R.sub.1 and R.sub.12 may each independently be the same as described in connection with R.sub.1 in Formula 1, and R.sub.1 and R.sub.12 may not each be hydrogen,

[0101] R.sub.1 and R.sub.12 may be optionally be bound to each other to form a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a,

[0102] R.sub.10a may be the same as described in connection with R.sub.10a in Formula 1,

[0103] * indicates a binding site to M in Formula 1,

[0104] *′ indicates a binding site to T.sub.4 in Formula 1,

[0105] *″ indicates a binding site to T.sub.1 in Formula 1, and

[0106] *′″ indicates a binding site to Y.sub.1 in Formula 1.

[0107] In an embodiment, in Formula 1, a group represented by

##STR00015##

may be a group represented by one of Formulae A2-1 to A2-8:

##STR00016##

[0108] In Formulae A2-1 to A2-8,

[0109] X.sub.2 may be the same as described in connection with X.sub.2 in Formula 1,

[0110] X.sub.21 to X.sub.23 may independently each be the same as described in connection with X.sub.2 in Formula 1,

[0111] R.sub.21 to R.sub.23 may each independently be the same as described in connection with R.sub.2 in Formula 1, and R.sub.21 to R.sub.23 may not each be hydrogen,

[0112] two of R.sub.21 to R.sub.23 may optionally be bound to each other to form a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a,

[0113] R.sub.10a may be the same as described in connection with R.sub.10a in Formula 1,

[0114] * indicates a binding site to M in Formula 1,

[0115] *′ indicates a binding site to T.sub.2 in Formula 1, and

[0116] *″ indicates a binding site to T.sub.1 in Formula 1.

[0117] In an embodiment, in Formula 1, a group represented by

##STR00017##

may be a group represented by one of Formulae A3-1 to A3-15:

##STR00018##

[0118] In Formulae A3-1 to A3-15,

[0119] X.sub.3 may be the same as described in connection with X.sub.3 in Formula 1,

[0120] X.sub.32 to X.sub.37 may each independently be the same as described in connection with X.sub.3 in Formula 1,

[0121] R.sub.31 to R.sub.34 may each independently be the same as described in connection with R.sub.3 in Formula 1, and R.sub.31 to R.sub.33 may not each be hydrogen,

[0122] b34 may be an integer from 0 to 4,

[0123] two of R.sub.31 to R.sub.34 may optionally be bound to each other to form a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a, two R.sub.34(s) of at least two R.sub.34(s) when b34 is 2 or greater may optionally be bound to each other to form a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a,

[0124] R.sub.10a may be the same as described in connection with R.sub.10a in Formula 1,

[0125] * indicates a binding site to M in Formula 1,

[0126] *″ indicates a binding site to T.sub.2 in Formula 1, and

[0127] *′ in Formulae A3-9 to A3-12 and A3-15 may be a binding site to T.sub.3 in Formula 1.

[0128] In an embodiment, in Formula 1, a group represented by

##STR00019##

may be a group represented by one of Formulae A4-1 to A4-32:

##STR00020## ##STR00021##

[0129] In Formulae A4-1 to A4-32,

[0130] X.sub.4 may be the same as described in connection with X.sub.4 in Formula 1,

[0131] X.sub.41 to X.sub.47 may each independently be the same as described in connection with X.sub.4 in Formula 1,

[0132] R.sub.41 to R.sub.45 may each independently be the same as described in connection with R.sub.4 in Formula 1, and R.sub.41 to R.sub.43 may not each be hydrogen,

[0133] R.sub.44 in Formulae A4-20, A4-25, A4-26, and A4-28 to A4-30 may not be hydrogen,

[0134] b43 may be an integer from 0 to 3,

[0135] b44 may be an integer from 0 to 4,

[0136] two of R.sub.41 to R.sub.45 may optionally be bound to each other to form a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a, two R.sub.44(s) of at least two R.sub.44(s) when b44 is 2 or greater may optionally be bound to each other to form a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a, two R.sub.45(s) of at least two R.sub.45(s) when b43 is 2 or greater may optionally be bound to each other to form a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a,

[0137] R.sub.10a may be the same as described in connection with R.sub.10a in Formula 1,

[0138] * indicates a binding site to M in Formula 1,

[0139] *″ indicates a binding site to T.sub.4 in Formula 1, and

[0140] *′ in Formulae A4-9 to A4-12, A4-15, A4-31, and A4-32 may be a binding site to T.sub.3 in Formula 1.

[0141] In Formula 1, CY.sub.1 may be a C.sub.1-C.sub.60 heterocyclic group.

[0142] In an embodiment, in Formula 1, CY.sub.1 may be a Y.sub.1-containing 5-membered ring, a Y.sub.1-containing 5-membered ring condensed with at least one 6-membered ring, or a Y.sub.1-containing 6-membered ring.

[0143] In an embodiment, the Y.sub.1-containing 5-membered ring or the Y.sub.1-containing 5-membered ring condensed ring with at least one 6-membered ring in CY.sub.1 may each independently be a pyrrole group, a pyrazole group, an imidazole group, a triazole group, an oxazole group, an isooxazole group, an isothiazole group, an oxadiazole group, or a thiadiazole group.

[0144] In an embodiment, the Y.sub.1-containing 6-membered ring in CY.sub.1 may be a pyridine group or a pyrimidine group.

[0145] In embodiments, in Formula 1, a group represented by

##STR00022##

may be a group represented by Formula CY1(a):

##STR00023##

[0146] In Formula CY1(a),

[0147] Y.sub.1a may be C or N,

[0148] CY.sub.11 may be a C.sub.3-C.sub.60 carbocyclic group or a C.sub.1-C.sub.60 heterocyclic group,

[0149] CY.sub.12 may be the same as described in connection with CY.sub.1 in Formula 1,

[0150] R.sub.5a and R.sub.5b may each independently be the same as described in connection with R.sub.5 in Formula 1,

[0151] b5a and b5b may each independently be the same as described in connection with b5 in Formula 1,

[0152] two R.sub.5a(s) of at least two R.sub.5a(s) when b5a is 2 or greater may optionally be bound to each other to form a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a, two R.sub.5b(s) of at least two R.sub.5b(s) when b5b is 2 or greater may optionally be bound to each other to form a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a,

[0153] R.sub.10a may be the same as described in connection with R.sub.10a in Formula 1,

[0154] *′ indicates a binding site to A.sub.1 in Formula 1, and

[0155] *″ indicates a binding site to T.sub.1 in Formula 1.

[0156] In an embodiment, in Formula 1, a group represented by

##STR00024##

may be a group represented by Formula CY1-1 or Formula CY1-2:

##STR00025##

[0157] In Formulae CY1-1 and CY1-2,

[0158] Y.sub.12 to Y.sub.18 may each independently be C or N,

[0159] R.sub.51 and R.sub.52 may each independently be the same as described in connection with R.sub.5 in Formula 1,

[0160] b52 may be an integer from 0 to 2,

[0161] b53 may be an integer from 0 to 3,

[0162] b54 may be an integer from 0 to 4,

[0163] two R.sub.51(s) of at least two R.sub.51(s) when b53 is 2 or greater may optionally be bound to each other to form a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a, two R.sub.52(s) when b52 is 2 may optionally be bound to each other to form a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a, two R.sub.52(s) of at least two R.sub.52(s) when b54 is 2 or greater may optionally be bound to each other to form a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a,

[0164] R.sub.10a may be the same as described in connection with R.sub.10a in Formula 1,

[0165] *′ indicates a binding site to A.sub.1 in Formula 1, and

[0166] *″ indicates a binding site to T.sub.1 in Formula 1.

[0167] In Formula 1, T.sub.1 may be N, B, P, C(Z.sub.11), Si(Z.sub.11), or Ge(Z.sub.11).

[0168] In an embodiment, in Formula 1, T.sub.1 may be N or C(Z.sub.11), but embodiments are not limited thereto.

[0169] In Formula 1, T.sub.2 to T.sub.4 may each independently be a single bond, a double bond, *—N(Z.sub.21)—*′, *—B(Z.sub.21)—*′, *—P(Z.sub.21)—*′, *—C(Z.sub.21)(Z.sub.22)—*′, *—Si(Z.sub.21)(Z.sub.22)—*′, *—Ge(Z.sub.21)(Z.sub.22)—*′, *—S—*′, *—Se—*′, *—O—*′, *—C(═O)—*′, *—S(═O)—*′, *—S(═O).sub.2—*′, *—C(Z.sub.21)=*′, *═C(Z.sub.21)—*′, *—C(Z.sub.21)═C(Z.sub.22)—*′, *—C(═S)—*′, or *—C≡C—*′, and * and *′ each indicate a binding site to an adjacent atom.

[0170] In an embodiment, T.sub.2 to T.sub.4 may each be a single bond, but embodiments are not limited thereto.

[0171] In Formula 1, a2 to a4 may each independently be an integer from 0 to 3.

[0172] In an embodiment, in Formula 1, a2 to a4 may each independently be 0 or 1.

[0173] In an embodiment, in Formula 1, a2 and a4 may each be 1, but embodiments are not limited thereto.

[0174] In an embodiment, in Formula 1, a3 may be 0, but embodiments are not limited thereto.

[0175] In Formula 1, R.sub.1 to R.sub.5, Z.sub.11, Z.sub.12, Z.sub.21, and Z.sub.22 may each independently be hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, a C.sub.1-C.sub.60 alkyl group unsubstituted or substituted with at least one R.sub.10a, a C.sub.2-C.sub.60 alkenyl group unsubstituted or substituted with at least one R.sub.10a, a C.sub.2-C.sub.60 alkynyl group unsubstituted or substituted with at least one R.sub.10a, a C.sub.1-C.sub.60 alkoxy group unsubstituted or substituted with at least one R.sub.10a, a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a, a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a, a C.sub.6-C.sub.60 aryloxy group unsubstituted or substituted with at least one R.sub.10a, a C.sub.6-C.sub.60 arylthio group unsubstituted or substituted with at least one R.sub.10a, —Si(Q.sub.1)(Q.sub.2)(Q.sub.3), —N(Q.sub.1)(Q.sub.2), —B(Q.sub.1)(Q.sub.2), —C(═O)(Q.sub.1), —S(═O).sub.2(Q.sub.1), or —P(═O)(Q.sub.1)(Q.sub.2). R.sub.10a and Q.sub.1 to Q.sub.3 may be understood by referring to the descriptions of R.sub.10a and Q.sub.1 to Q.sub.3 provided herein.

[0176] In an embodiment, in Formula 1, R.sub.1 to R.sub.5, Z.sub.11, Z.sub.21, and Z.sub.22 may respectively be understood by referring to the descriptions of R.sub.1 to R.sub.5, Z.sub.11, Z.sub.21, and Z.sub.22 in paragraph [00253] to [00274] of the disclosure.

[0177] In an embodiment, R.sub.1 to R.sub.5, Z.sub.11, Z.sub.21, and Z.sub.22 may each independently be:

[0178] hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, or a nitro group;

[0179] a C.sub.1-C.sub.20 alkyl group, a C.sub.2-C.sub.20 alkenyl group, a C.sub.2-C.sub.20 alkynyl group, or a C.sub.1-C.sub.20 alkoxy group, each unsubstituted or substituted with deuterium, —F, —Cl, —Br, —I, —CD.sub.3, —CD.sub.2H, —CDH.sub.2, —CF.sub.3, —CF.sub.2H, —CFH.sub.2, a hydroxyl group, a cyano group, a nitro group, a phenyl group, a naphthyl group, —Si(Q.sub.31)(Q.sub.32)(Q.sub.33), —N(Q.sub.31)(Q.sub.32), —B(Q.sub.31)(Q.sub.32), or any combination thereof;

[0180] a phenyl group, a naphthyl group, a fluorenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, or a chrysenyl group, each unsubstituted or substituted with deuterium, —F, —Cl, —Br, —I, —CD.sub.3, —CD.sub.2H, —CDH.sub.2, —CF.sub.3, —CF.sub.2H, —CFH.sub.2, a hydroxyl group, a cyano group, a nitro group, a C.sub.1-C.sub.20 alkyl group, a C.sub.2-C.sub.20 alkenyl group, a C.sub.2-C.sub.20 alkynyl group, a C.sub.1-C.sub.20 alkoxy group, a phenyl group, a naphthyl group, a fluorenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, —Si(Q.sub.31)(Q.sub.32)(Q.sub.33), —N(Q.sub.31)(Q.sub.32), —B(Q.sub.31)(Q.sub.32), or any combination thereof; or

[0181] —Si(Q.sub.1)(Q.sub.2)(Q.sub.3), —N(Q.sub.1)(Q.sub.2), or —B(Q.sub.1)(Q.sub.2).

[0182] In Formula 1, b1 to b5 may each independently be an integer from 0 to 10.

[0183] In an embodiment, in Formula 1, b1 to b5 may each independently be an integer from 0 to 5.

[0184] In Formula 1, two R.sub.1(s) of at least two R.sub.1(s) when b1 is 2 or greater may optionally be bound to each other to form a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a, two R.sub.2(s) of at least two R.sub.2(s) when b2 is 2 or greater may optionally be bound to each other to form a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a, two R.sub.3(s) of at least two R.sub.3(s) when b3 is 2 or greater may optionally be bound to each other to form a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a, two R.sub.4(s) of at least two R.sub.4(s) when b4 is 2 or greater may optionally be bound to each other to form a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a, and two R.sub.5(s) of at least two R.sub.5(s) when b5 is 2 or greater may optionally be bound to each other to form a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a.

[0185] In an embodiment, the organometallic compound represented by Formula 1 may be selected from Compounds 1 to 105:

##STR00026## ##STR00027## ##STR00028## ##STR00029## ##STR00030## ##STR00031## ##STR00032## ##STR00033## ##STR00034## ##STR00035## ##STR00036##

[0186] In embodiments, the organometallic compound represented by Formula 1 may emit blue light. In embodiments, the organometallic compound represented by Formula 1 may emit blue light having a maximum emission wavelength in a range of about 430 nanometers (nm) to about 490 nm. For example, the organometallic compound represented by Formula 1 may emit blue light having a maximum emission wavelength in a range of about 430 nm to about 485 nm. For example, the organometallic compound represented by Formula 1 may emit blue light having a maximum emission wavelength in a range of about 440 nm to about 475 nm. For example, the organometallic compound represented by Formula 1 may emit blue light having a maximum emission wavelength in a range of about 455 nm to about 470 nm.

[0187] In the organometallic compound represented by Formula 1, Y.sub.1 in Formula 1 may be N, and thus, the organometallic compound may have a non-planar structure. In Formula 1, a degree of intramolecular conjugation may be adjusted in the organometallic compound in which T.sub.1 is C(Z.sub.11) or N. Thus, in the light-emitting device including the organometallic compound, formation of exciplex or excimer may be prevented between a dopant and a dopant or between a dopant and a host. Accordingly, the light-emitting device may be used in the manufacture of an electronic apparatus having a low driving voltage, excellent luminescence efficiency, long lifespan, and excellent colorimetric purity.

[0188] Methods of synthesizing the organometallic compound represented by Formula 1 may be easily understood to those of ordinary skill in the art by referring to Synthesis Examples and Examples described herein.

[0189] According to embodiments, at least one of the organometallic compounds represented by Formula 1 may be used in a light-emitting device (e.g., an organic light-emitting device). Therefore, according to an embodiment, a light-emitting device may include a first electrode, a second electrode facing the first electrode, an interlayer disposed between the first electrode and the second electrode and including an emission layer, and the organometallic compound represented by Formula 1.

[0190] In an embodiment, the interlayer in the light-emitting device may include a first compound as the organometallic compound represented by Formula 1; and a second compound including at least one π electron-deficient nitrogen-containing C.sub.1-C.sub.60 cyclic group, a third compound including a group represented by Formula 3, a fourth compound that may emit delayed fluorescence, or any combination thereof, wherein the first compound, the second compound, the third compound, and the fourth compound may be different from one another:

##STR00037##

[0191] In Formula 3, ring CY.sub.71 and ring CY.sub.72 may each independently be a R electron-rich C.sub.3-C.sub.60 cyclic group or a pyridine group,

[0192] X.sub.71 may be a single bond or a linking group including O, S, N, B, C, Si, or any combination thereof,

[0193] * in Formula 3 indicates a binding site to an adjacent atom in the third compound, and

[0194] the following compounds may be excluded from the third compound:

##STR00038##

[0195] [Descriptions of Second Compound, Third Compound, and Fourth Compound]

[0196] In an embodiment, the second compound may include a pyridine group, a pyrimidine group, a pyrazine group, a pyridazine group, a triazine group, or any combination thereof.

[0197] In embodiments, the light-emitting device may further include at least one of the second compound and the third compound, in addition to the first compound.

[0198] In embodiments, the light-emitting device may further include the fourth compound, in addition to the first compound.

[0199] In embodiments, the light-emitting device may include the first compound, the second compound, the third compound, and the fourth compound.

[0200] In embodiments, the interlayer may include the second compound. The interlayer may further include, in addition to the first compound and the second compound, the third compound, the fourth compound, or any combination thereof.

[0201] In embodiments, a difference between the triplet energy level in electron volts (eV) of the fourth compound and the singlet energy level in electron volts (eV) of the fourth compound may be in a range of about 0 eV to about 0.5 eV. For example, the difference between the triplet energy level in electron volts (eV) of the fourth compound and the singlet energy level in electron volts (eV) of the fourth compound may be in a range of about 0 eV to about 0.3 eV.

[0202] In embodiments, the fourth compound may be a compound including at least one cyclic group including boron (B) and nitrogen (N) as ring-forming atoms.

[0203] In embodiments, the fourth compound may be a C.sub.8-C.sub.60 polycyclic group-containing compound including at least two condensed cyclic groups that share a boron atom (B).

[0204] In embodiments, the fourth compound may include a condensed ring in which at least one third ring may be condensed with at least one fourth ring,

[0205] the third ring may be a cyclopentane group, a cyclohexane group, a cycloheptane group, a cyclooctane group, a cyclopentene group, a cyclohexene group, a cycloheptene group, a cyclooctene group, an adamantane group, a norbornene group, a norobornane group, a bicyclo[1.1.1]pentane group, a bicyclo[2.1.1]hexane group, a bicyclo[2.2.2]octane group, a benzene group, a pyridine group, a pyrimidine group, a pyridazine group, a pyrazine group, or a triazine group, and

[0206] the fourth ring may be a 1,2-azaborinine group, a 1,3-azaborinine group, a 1,4-azaborinine group, a 1,2-dihydro-1,2-azaborinine group, a 1,4-oxaborinine group, a 1,4-thiaborinine group, or a 1,4-dihydroborinine group.

[0207] In embodiments, the interlayer may include the fourth compound. The interlayer may include, in addition to the first compound and the fourth compound, the second compound, the third compound, or any combination thereof.

[0208] In embodiments, the interlayer may include the third compound. For example, the third compound may not include CBP described herein and a compound represented by mCBP.

[0209] In an embodiment, the emission layer in the interlayer may include: the first compound; and the second compound, the third compound, the fourth compound, or any combination thereof.

[0210] In an embodiment, the emission layer may emit phosphorescence or fluorescence emitted from the first compound. In embodiments, phosphorescence or fluorescence emitted from the first compound may be blue light.

[0211] In embodiments, the emission layer in the light-emitting device may include the first compound and the second compound, and the first compound and the second compound may form an exciplex.

[0212] In embodiments, the emission layer in the light-emitting device may include the first compound, the second compound, and the third compound, and the first compound and the second compound may form an exciplex.

[0213] In embodiments, the emission layer in the light-emitting device may include the first compound and the fourth compound, and the fourth compound may improve color purity, luminescence efficiency, and lifespan characteristics of the light-emitting device.

[0214] In embodiments, the second compound may include a compound represented by Formula 2:

##STR00039##

[0215] In Formula 2,

[0216] L.sub.61 to L.sub.63 may each independently be a single bond, a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a, or a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a,

[0217] b61 to b63 may each independently be an integer from 1 to 5,

[0218] X.sub.64 may be N or C(R.sub.64), X.sub.65 may be N or C(R.sub.65), X.sub.66 may be N or C(R.sub.66), and at least one of X.sub.64 to X.sub.66 may be N,

[0219] R.sub.61 to R.sub.66 may respectively be understood by referring to the descriptions of R.sub.61 to R.sub.66 provided herein, and

[0220] R.sub.10a may be understood by referring to the description of R.sub.10a provided herein.

[0221] In embodiments, the third compound may include a compound represented by Formula 3-1, a compound represented by Formula 3-2, a compound represented by Formula 3-3, a compound represented by Formula 3-4, a compound represented by Formula 3-5, or any combination thereof:

##STR00040## ##STR00041##

[0222] In Formulae 3-1 to 3-5,

[0223] ring CY.sub.71 to ring CY.sub.74 may each independently be a π electron-rich C.sub.3-C.sub.60 cyclic group or a pyridine group,

[0224] X.sub.82 may be a single bond, O, S, N-[(L.sub.82).sub.b82-R.sub.82], C(R.sub.82a)(R.sub.82b), or Si(R.sub.82a)(R.sub.82b),

[0225] X.sub.83 may be a single bond, O, S, N-[(L.sub.83).sub.b83-R.sub.83], C(R.sub.83a)(R.sub.83b), or Si(R.sub.83a)(R.sub.83b),

[0226] X.sub.84 may be O, S, N-[(L.sub.84).sub.b84-R.sub.84], C(R.sub.84a)(R.sub.84b), or Si(R.sub.84a)(R.sub.84b),

[0227] X.sub.85 may be C or Si,

[0228] L.sub.81 to L.sub.85 may each independently be a single bond, *—C(Q.sub.4)(Q.sub.5)-*′, *—Si(Q.sub.4)(Q.sub.5)-*′, a π electron-rich C.sub.3-C.sub.60 cyclic group unsubstituted or substituted with at least one R.sub.10a, or a pyridine group unsubstituted or substituted with at least one R.sub.10a, wherein Q.sub.4 and Q.sub.5 may each independently be the same as defined in connection with Q.sub.1 provided herein, * and *′ each indicate a binding site to a neighboring atom,

[0229] b81 to b85 may each independently be an integer from 1 to 5,

[0230] R.sub.71 to R.sub.74, R.sub.81 to R.sub.85, R.sub.82a, R.sub.82b, R.sub.83a, R.sub.83b, R.sub.84a, and R.sub.84b may respectively be understood by referring to the descriptions of R.sub.71 to R.sub.74, R.sub.81 to R.sub.85, R.sub.82a, R.sub.82b, R.sub.83a, R.sub.83b, R.sub.84a, and R.sub.84b provided herein,

[0231] a71 to a74 may each independently be an integer from 0 to 20, and

[0232] R.sub.10a may be understood by referring to the description of R.sub.10a provided herein.

[0233] In embodiments, the fourth compound may be a compound represented by Formula 502, a compound represented by Formula 503, or any combination thereof:

##STR00042##

[0234] In Formulae 502 and 503,

[0235] ring A.sub.501 to ring A.sub.504 may each independently be a C.sub.3-C.sub.60 carbocyclic group or a C.sub.1-C.sub.60 heterocyclic group,

[0236] Y.sub.505 may be O, S, N(R.sub.505), B(R.sub.505), C(R.sub.505a)(R.sub.505b), or Si(R.sub.505a)(R.sub.505b),

[0237] Y.sub.506 may be O, S, N(R.sub.506), B(R.sub.506), C(R.sub.506a)(R.sub.506b), or Si(R.sub.506a)(R.sub.506b),

[0238] Y.sub.507 may be O, S, N(R.sub.507), B(R.sub.507), C(R.sub.507a)(R.sub.507b), or Si(R.sub.507a)(R.sub.507b),

[0239] Y.sub.508 may be O, S, N(R.sub.508), B(R.sub.508), C(R.sub.508a)(R.sub.508b), or Si(R.sub.508a)(R.sub.508b),

[0240] Y.sub.51 and Y.sub.52 may each independently be B, P(═O), or S(═O),

[0241] R.sub.500a, R.sub.500b, R.sub.501 to R.sub.508, R.sub.505a, R.sub.505b, R.sub.506a, R.sub.506b, R.sub.507a, R.sub.507b, R.sub.508a, and R.sub.508b may respectively be understood by referring to the descriptions of R.sub.500a, R.sub.500b, R.sub.501 to R.sub.508, R.sub.505a, R.sub.505b, R.sub.506a, R.sub.506b, R.sub.507a, R.sub.507b, R.sub.508a, and R.sub.508b provided herein,

[0242] a501 to a504 may each independently be an integer from 0 to 20, and

[0243] R.sub.10a may be understood by referring to the description of R.sub.10a provided herein.

[0244] [Description of Formulae 2, 3, 3-1 to 3-5, 502, and 503]

[0245] In Formula 2, b61 to b63 may respectively indicate the number of L.sub.61(s) to L.sub.63(s), and b61 to b63 may each independently be an integer from 1 to 5. When b61 is 2 or greater, at least two L.sub.61(s) may be identical to or different from each other, when b62 is 2 or greater, at least two L.sub.62(s) may be identical to or different from each other, and when b63 is 2 or greater, at least two L.sub.63(s) may be identical to or different from each other. In embodiments, b61 to b63 may each independently be 1 or 2.

[0246] In an embodiment, in Formula 2, L.sub.61 to L.sub.63 may each independently be:

[0247] a single bond; or

[0248] a benzene group, a naphthalene group, an anthracene group, a phenanthrene group, a triphenylene group, a pyrene group, a chrysene group, a cyclopentadiene group, a furan group, a thiophene group, a silole group, an indene group, a fluorene group, an indole group, a carbazole group, a benzofuran group, a dibenzofuran group, a benzothiophene group, a dibenzothiophene group, a benzosilole group, a dibenzosilole group, an azafluorene group, an azacarbazole group, an azadibenzofuran group, an azadibenzothiophene group, an azadibenzosilole group, a pyridine group, a pyrimidine group, a pyrazine group, a pyridazine group, a triazine group, a quinoline group, an isoquinoline group, a quinoxaline group, a quinazoline group, a phenanthroline group, a pyrrole group, a pyrazole group, an imidazole group, a triazole group, an oxazole group, an isooxazole group, a thiazole group, an isothiazole group, an oxadiazole group, a thiadiazole group, a benzopyrazole group, a benzimidazole group, a benzoxazole group, a benzothiazole group, a benzoxadiazole group, a benzothiadiazole group, a dibenzooxasiline group, a dibenzothiasiline group, a dibenzodihydroazasiline group, a dibenzodihydrodisiline group, a dibenzodihydrosiline group, a dibenzodioxane group, a dibenzooxathiene group, a dibenzooxazine group, a dibenzopyran group, a dibenzodithiine group, a dibenzothiazine group, a dibenzothiopyran group, a dibenzocyclohexadiene group, a dibenzodihydropyridine group, or a dibenzodihydropyrazine group, each unsubstituted or substituted with deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, a C.sub.1-C.sub.20 alkyl group, a C.sub.1-C.sub.20 alkoxy group, a phenyl group, a naphthyl group, a pyridinyl group, a pyrimidinyl group, a triazinyl group, a fluorenyl group, a dimethylfluorenyl group, a diphenylfluorenyl group, a carbazolyl group, a phenylcarbazolyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a dibenzosilolyl group, a dimethyldibenzosilolyl group, a diphenyldibenzosilolyl group, —O(Q.sub.31), —S(Q.sub.31), —Si(Q.sub.31)(Q.sub.32)(Q.sub.33), —N(Q.sub.31)(Q.sub.32), —B(Q.sub.31)(Q.sub.32), —P(Q.sub.31)(Q.sub.32), —C(═O)(Q.sub.31), —S(═O).sub.2(Q.sub.31), —P(═O)(Q.sub.31)(Q.sub.32), or any combination thereof,

[0249] wherein Q.sub.31 to Q.sub.33 may each independently be hydrogen, deuterium, a C.sub.1-C.sub.20 alkyl group, a C.sub.1-C.sub.20 alkoxy group, a phenyl group, a biphenyl group, a terphenyl group, a pyridinyl group, a pyrimidinyl group, a pyridazinyl group, a pyrazinyl group, or a triazinyl group.

[0250] In embodiments, in Formula 2, a bond between L.sub.61 and R.sub.61, a bond between L.sub.62 and R.sub.62, a bond between L.sub.63 and R.sub.63, a bond between at least two L.sub.61(s), a bond between at least two L.sub.62(s), a bond between at least two L.sub.63(s), a bond between L.sub.61 and a carbon atom between X.sub.64 and X.sub.65 in Formula 2, a bond between L.sub.62 and a carbon atom between X.sub.64 and X.sub.66 in Formula 2, and a bond between L.sub.63 and a carbon atom between X.sub.65 and X.sub.66 in Formula 2 may each be a carbon-carbon single bond.

[0251] In Formula 2, X.sub.64 may be N or C(R.sub.64), X.sub.65 may be N or C(R.sub.65), X.sub.66 may be N or C(R.sub.66), and at least one of X.sub.64 to X.sub.66 may be N. R.sub.64 to R.sub.66 may respectively be understood by referring to the descriptions of R.sub.64 to R.sub.66 provided herein. In embodiments, two or three of X.sub.64 to X.sub.66 may each be N.

[0252] R.sub.61 to R.sub.66, R.sub.71 to R.sub.74, R.sub.81 to R.sub.85, R.sub.82a, R.sub.82b, R.sub.83a, R.sub.83b, R.sub.84a and R.sub.84b, R.sub.500a, R.sub.500b, R.sub.501 to R.sub.508, R.sub.505a, R.sub.505b, R.sub.506a, R.sub.506b, R.sub.507a, R.sub.507b, R.sub.508a, and R.sub.508b may each independently be hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, a C.sub.1-C.sub.60 alkyl group unsubstituted or substituted with at least one R.sub.10a, a C.sub.2-C.sub.60 alkenyl group unsubstituted or substituted with at least one R.sub.10a, a C.sub.2-C.sub.60 alkynyl group unsubstituted or substituted with at least one R.sub.10a, a C.sub.1-C.sub.60 alkoxy group unsubstituted or substituted with at least one R.sub.10a, a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a, a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a, a C.sub.6-C.sub.60 aryloxy group unsubstituted or substituted with at least one R.sub.10a, a C.sub.6-C.sub.60 arylthio group unsubstituted or substituted with at least one R.sub.10a, —C(Q.sub.1)(Q.sub.2)(Q.sub.3), —Si(Q.sub.1)(Q.sub.2)(Q.sub.3), —N(Q.sub.1)(Q.sub.2), —B(Q.sub.1)(Q.sub.2), —C(═O)(Q.sub.1), —S(═O).sub.2(Q.sub.1), or —P(═O)(Q.sub.1)(Q.sub.2). Q.sub.1 to Q.sub.3 may respectively be understood by referring to the descriptions of Q.sub.1 to Q.sub.3 provided herein.

[0253] For example, i) R.sub.1 to R.sub.5, Z.sub.11, Z.sub.21, and Z.sub.22 in Formula 1, ii) R.sub.11, R.sub.12, R.sub.21, R.sub.22, R.sub.31 to R.sub.34, R.sub.41 to R.sub.45, R.sub.5a, R.sub.5b, R.sub.51, and R.sub.52 in Formulae A1(1) to A1(32), A1-1 to A1-4, A2-1 to A2-8, A3-1 to A3-15, A4-1 to A4-32, CY1(a), CY1-1, and CY1-2, iii) R.sub.51 to R.sub.56, R.sub.71 to R.sub.74, R.sub.81 to R.sub.85, R.sub.82a, R.sub.82b, R.sub.83a, R.sub.83b, R.sub.84a and R.sub.84b, R.sub.500a, R.sub.500b, R.sub.501 to R.sub.508, R.sub.505a, R.sub.505b, R.sub.506a, R.sub.506b, R.sub.507a, R.sub.507b, R.sub.508a, and R.sub.508b in Formulae 2, 3-1 to 3-5, 502, and 503, and iv) R.sub.10a may each independently be:

[0254] hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, a C.sub.1-C.sub.20 alkyl group, or a C.sub.1-C.sub.20 alkoxy group;

[0255] a C.sub.1-C.sub.20 alkyl group or a C.sub.1-C.sub.20 alkoxy group, each substituted with deuterium, —F, —Cl, —Br, —I, —CD.sub.3, —CD.sub.2H, —CDH.sub.2, —CF.sub.3, —CF.sub.2H, —CFH.sub.2, a hydroxyl group, a cyano group, a nitro group, a C.sub.1-C.sub.10 alkyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, an adamantanyl group, a norbornanyl group, a norbornenyl group, a cyclopentenyl group, a cyclohexenyl group, a cycloheptenyl group, a phenyl group, a biphenyl group, a naphthyl group, a pyridinyl group, a pyrimidinyl group, or any combination thereof,

[0256] a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, an adamantanyl group, a norbornanyl group, a norbornenyl group, a cyclopentenyl group, a cyclohexenyl group, a cycloheptenyl group, a phenyl group, a biphenyl group, a C.sub.1-C.sub.10 alkylphenyl group, a naphthyl group, a fluorenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a pyrrolyl group, a thiophenyl group, a furanyl group, an imidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolyl group, an isoxazolyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, an isoindolyl group, an indolyl group, an indazolyl group, a purinyl group, a quinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, a cinnolinyl group, a carbazolyl group, a phenanthrolinyl group, a benzimidazolyl group, a benzofuranyl group, a benzothiophenyl group, a benzoisothiazolyl group, a benzoxazolyl group, a benzoisoxazolyl group, a triazolyl group, a tetrazolyl group, an oxadiazolyl group, a triazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, an imidazopyridinyl group, an imidazopyrimidinyl group, an azacarbazolyl group, an azadibenzofuranyl group, an azadibenzothiophenyl group, an azafluorenyl group, an azadibenzosilolyl group, or a group represented by Formula 91, each unsubstituted or substituted with deuterium, —F, —Cl, —Br, —I, —CD.sub.3, —CD.sub.2H, —CDH.sub.2, —CF.sub.3, —CF.sub.2H, —CFH.sub.2, a hydroxyl group, a cyano group, a nitro group, a C.sub.1-C.sub.20 alkyl group, a C.sub.1-C.sub.20 alkoxy group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, an adamantanyl group, a norbornanyl group, a norbornenyl group, a cyclopentenyl group, a cyclohexenyl group, a cycloheptenyl group, a phenyl group, a biphenyl group, a C.sub.1-C.sub.10 alkylphenyl group, a naphthyl group, a fluorenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a pyrrolyl group, a thiophenyl group, a furanyl group, an imidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolyl group, an isoxazolyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, an isoindolyl group, an indolyl group, an indazolyl group, a purinyl group, a quinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, a cinnolinyl group, a carbazolyl group, a phenanthrolinyl group, a benzimidazolyl group, a benzofuranyl group, a benzothiophenyl group, a benzoisothiazolylgroup, a benzoxazolyl group, a benzoisoxazolyl group, a triazolyl group, a tetrazolyl group, an oxadiazolyl group, a triazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, an imidazopyridinyl group, an imidazopyrimidinyl group, —O(Q.sub.31), —S(Q.sub.31), —Si(Q.sub.31)(Q.sub.32)(Q.sub.33), —N(Q.sub.31)(Q.sub.32), —B(Q.sub.31)(Q.sub.32), —P(Q.sub.31)(Q.sub.32), —C(═O)(Q.sub.31), —S(═O).sub.2(Q.sub.31), —P(═O)(Q.sub.31)(Q.sub.32), or any combination thereof; or

[0257] —C(Q.sub.1)(Q.sub.2)(Q.sub.3), —Si(Q.sub.1)(Q.sub.2)(Q.sub.3), —N(Q.sub.1)(Q.sub.2), —B(Q.sub.1)(Q.sub.2), —C(═O)(Q.sub.1), —S(═O).sub.2(Q.sub.1), or —P(═O)(Q.sub.1)(Q.sub.2),

[0258] wherein Q.sub.1 to Q.sub.3 and Q.sub.31 to Q.sub.33 may each independently be selected from:

[0259] —CH.sub.3, —CD.sub.3, —CD.sub.2H, —CDH.sub.2, —CH.sub.2CH.sub.3, —CH.sub.2CD.sub.3, —CH.sub.2CD.sub.2H, —CH.sub.2CDH.sub.2, —CHDCH.sub.3, —CHDCD.sub.2H, —CHDCDH.sub.2, —CHDCD.sub.3, —CD.sub.2CD.sub.3, —CD.sub.2CD.sub.2H, or —CD.sub.2CDH.sub.2; or

[0260] an n-propyl group, an iso-propyl group, an n-butyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, an n-pentyl group, an isopentyl group, a sec-pentyl group, a tert-pentyl group, a phenyl group, a naphthyl group, a pyridinyl group, a pyrimidinyl group, a pyridazinyl group, a pyrazinyl group, or a triazinyl group, each unsubstituted or substituted with deuterium, a C.sub.1-C.sub.10 alkyl group, a phenyl group, a biphenyl group, a pyridinyl group, a pyrimidinyl group, a pyridazinyl group, a pyrazinyl group, a triazinyl group, or any combination thereof:

##STR00043##

[0261] wherein in Formula 91,

[0262] ring CY.sub.91 and ring CY.sub.92 may each independently be a C.sub.5-C.sub.30 carbocyclic group unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.30 heterocyclic group unsubstituted or substituted with at least one R.sub.10a,

[0263] X.sub.91 may be a single bond, O, S, N(R.sub.91), B(R.sub.91), C(R.sub.91a)(R.sub.91b), or Si(R.sub.91a)(R.sub.91b),

[0264] R.sub.91, R.sub.91a, and R.sub.91b may respectively be the same as defined in connection with R.sub.82, R.sub.82a, and R.sub.82b provided herein,

[0265] R.sub.10a may be understood by referring to the description of R.sub.10a provided herein, and

[0266] * indicates a binding site to an adjacent atom.

[0267] In embodiments, in Formula 91,

[0268] ring CY.sub.91 and ring CY.sub.92 may each independently be a benzene group, a pyridine group, a pyrimidine group, a pyrazine group, a pyridazine group, or a triazine group, each unsubstituted or substituted with at least one R.sub.10a,

[0269] R.sub.91, R.sub.91a and R.sub.91b may each independently be:

[0270] hydrogen or a C.sub.1-C.sub.10 alkyl group; or

[0271] a phenyl group, a pyridinyl group, a pyrimidinyl group, a pyridazinyl group, a pyrazinyl group, or a triazinyl group, each unsubstituted or substituted with deuterium, a C.sub.1-C.sub.10 alkyl group, a phenyl group, a biphenyl group, a pyridinyl group, a pyrimidinyl group, a pyridazinyl group, a pyrazinyl group, a triazinyl group, or any combination thereof.

[0272] In embodiments, i) R.sub.1 to R.sub.5, Z.sub.11, Z.sub.21, and Z.sub.22 in Formula 1, ii) R.sub.11, R.sub.12, R.sub.21, R.sub.22, R.sub.31 to R.sub.34, R.sub.41 to R.sub.45, R.sub.5a, R.sub.5b, R.sub.51, and R.sub.52 in Formulae A1(1) to A1(32), A1-1 to A1-4, A2-1 to A2-8, A3-1 to A3-15, A4-1 to A4-32, CY1(a), CY1-1, and CY1-2, iii) R.sub.51 to R.sub.56, R.sub.71 to R.sub.74, R.sub.81 to R.sub.85, R.sub.82a, R.sub.82b, R.sub.83a, R.sub.83b, R.sub.84a and R.sub.84b, R.sub.500a, R.sub.500b, R.sub.501 to R.sub.508, R.sub.505a, R.sub.505b, R.sub.506a, R.sub.506b, R.sub.507a, R.sub.507b, R.sub.508a, and R.sub.508b in Formulae 2, 3-1 to 3-5, 502, and 503, and iv) R.sub.10a may each independently be:

[0273] hydrogen, deuterium, —F, a cyano group, a nitro group, —CH.sub.3, —CD.sub.3, —CD.sub.2H, —CDH.sub.2, —CF.sub.3, —CF.sub.2H, —CFH.sub.2, a group represented by one of Formulae 9-1 to 9-19, a group represented by one of Formulae 10-1 to 10-246, —C(Q.sub.1)(Q.sub.2)(Q.sub.3), —Si(Q.sub.1)(Q.sub.2)(Q.sub.3), or —P(═O)(Q.sub.1)(Q.sub.2), wherein Q.sub.1 to Q.sub.3 may respectively be understood by referring to the descriptions of Q.sub.1 to Q.sub.3 provided herein:

##STR00044## ##STR00045## ##STR00046## ##STR00047## ##STR00048## ##STR00049## ##STR00050## ##STR00051## ##STR00052## ##STR00053##

[0274] wherein, in Formulae 9-1 to 9-19 and 10-1 to 10-246, * indicates a binding site to an adjacent atom, “Ph” represents a phenyl group, and “TMS” represents a trimethylsilyl group.

[0275] In Formulae 3-1 to 3-5, 502, and 503, a71 to a74 and a501 to a504 may respectively indicate the number of R.sub.71(s) to R.sub.74(s) and R.sub.501(s) to R.sub.504(s), and a71 to a74 and a501 to a504 may each independently be an integer from 0 to 20. When a71 is 2 or greater, at least two R.sub.71(s) may be identical to or different from each other, when a72 is 2 or greater, at least two R.sub.72(s) may be identical to or different from each other, when a73 is 2 or greater, at least two R.sub.73(s) may be identical to or different from each other, when a74 is 2 or greater, at least two R.sub.74(s) may be identical to or different from each other, when a501 is 2 or greater, at least two R.sub.501(s) may be identical to or different from each other, when a502 is 2 or greater, at least two R.sub.502(s) may be identical to or different from each other, when a503 is 2 or greater, at least two R.sub.503(s) may be identical to or different from each other, and when a504 is 2 or greater, at least two R.sub.504(s) may be identical to or different from each other. In embodiments, a71 to a74 and a501 to a504 may each independently be an integer from 0 to 8.

[0276] In embodiments, in Formula 2, the group represented by *-(L.sub.61).sub.b61-R.sub.61 and the group represented by *-(L.sub.62).sub.b62-R.sub.62 may not be a phenyl group.

[0277] In embodiments, in Formula 2, the group represented by *-(L.sub.61).sub.b61-R.sub.61 may be identical to the group represented by *-(L.sub.62).sub.b62-R.sub.62.

[0278] In embodiments, in Formula 2, the group represented by *-(L.sub.61).sub.b61-R.sub.61 and the group represented by *-(L.sub.62).sub.b62-R.sub.62 may be different from each other.

[0279] In embodiments, in Formula 2, b61 and b62 may each independently be 1, 2, or 3, L.sub.61 and L.sub.62 may each independently be a benzene group, a pyridine group, a pyrimidine group, a pyridazine group, a pyrazine group, or a triazine group, each unsubstituted or substituted with at least one R.sub.10a.

[0280] In embodiments, in Formula 2, R.sub.61 and R.sub.62 may each independently be a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a, a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a, a C.sub.6-C.sub.60 aryloxy group unsubstituted or substituted with at least one R.sub.10a, a C.sub.6-C.sub.60 arylthio group unsubstituted or substituted with at least one R.sub.10a, —C(Q.sub.1)(Q.sub.2)(Q.sub.3), or —Si(Q.sub.1)(Q.sub.2)(Q.sub.3),

[0281] wherein Q.sub.1 to Q.sub.3 may each independently be a C.sub.3-C.sub.60 carbocyclic group or a C.sub.1-C.sub.60 heterocyclic group, each unsubstituted or substituted with deuterium, —F, a cyano group, a C.sub.1-C.sub.60 alkyl group, a C.sub.1-C.sub.60 alkoxy group, a phenyl group, a biphenyl group, or any combination thereof.

[0282] In embodiments,

[0283] in Formula 2, the group represented by *-(L.sub.61).sub.b61-R.sub.1 may be a group represented by one of Formulae CY51-1 to CY51-26,

[0284] in Formula 2, the group represented by *-(L.sub.62).sub.b62-R.sub.62 may be a group represented by one of Formulae CY52-1 to CY52-26, and/or

[0285] in Formula 2, the group represented by *-(L.sub.63).sub.b63-R.sub.63 may be a group represented by one of Formulae CY53-1 to CY53-27, —C(Q.sub.1)(Q.sub.2)(Q.sub.3), or —Si(Q.sub.1)(Q.sub.2)(Q.sub.3):

##STR00054## ##STR00055## ##STR00056## ##STR00057## ##STR00058## ##STR00059## ##STR00060## ##STR00061## ##STR00062## ##STR00063##

[0286] wherein in Formulae CY51-1 to CY51-26, CY52-1 to CY52-26, and CY53-1 to CY53-27,

[0287] Y.sub.63 may be a single bond, O, S, N(R.sub.63), B(R.sub.63), C(R.sub.63a)(.sub.63b), or Si(R.sub.63a)(R.sub.63b),

[0288] Y.sub.64 may be a single bond, O, S, N(R.sub.64), B(R.sub.64), C(R.sub.64a)(R.sub.64b), or Si(R.sub.64a)(R.sub.64b),

[0289] Y.sub.67 may be a single bond, O, S, N(R.sub.67), B(R.sub.67), C(R.sub.67a)(R.sub.67b), or Si(R.sub.67a)(R.sub.67b),

[0290] Y.sub.68 may be a single bond, O, S, N(R.sub.68), B(R.sub.6s), C(R.sub.68a)(R.sub.68b), or Si(R.sub.68a)(R.sub.68b),

[0291] Y.sub.63 and Y.sub.64 in Formulae CY51-16 and CY51-17 may not be a single bond at the same time,

[0292] Y.sub.67 and Y.sub.68 in Formulae CY52-16 and CY52-17 may not be a single bond at the same time,

[0293] R.sub.51a to R.sub.51e, R.sub.61 to R.sub.64, R.sub.63a, R.sub.63b, R.sub.64a, and R.sub.64b may each independently be the same as defined in connection with R.sub.51, and R.sub.51a to R.sub.51e may not each be hydrogen,

[0294] R.sub.52a to R.sub.52e, R.sub.65 to R.sub.68, R.sub.67a, R.sub.67b, R.sub.68a, and R.sub.68b may each independently be the same as defined in connection with R.sub.52, and R.sub.52a to R.sub.52e may not each be hydrogen,

[0295] R.sub.53a to R.sub.53e, R.sub.69a, and R.sub.69b may each independently be the same as defined in connection with R.sub.53, and R.sub.53a to R.sub.53e may not each be hydrogen, and

[0296] * indicates a binding site to an adjacent atom.

[0297] In embodiments,

[0298] R.sub.51a to R.sub.51e and R.sub.52a to R.sub.52e in Formulae CY51-1 to CY51-26 and Formulae CY52-1 to 52-26 may each independently be:

[0299] a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, an adamantanyl group, a norbornanyl group, a norbornenyl group, a cyclopentenyl group, a cyclohexenyl group, a cycloheptenyl group, a phenyl group, a biphenyl group, a C.sub.1-C.sub.10 alkylphenyl group, a naphthyl group, a fluorenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a pyrrolyl group, a thiophenyl group, a furanyl group, an imidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolyl group, an isoxazolyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, an isoindolyl group, an indolyl group, an indazolyl group, a purinyl group, a quinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, a cinnolinyl group, a carbazolyl group, a phenanthrolinyl group, a benzimidazolyl group, a benzofuranyl group, a benzothiophenyl group, a benzoisothiazolyl group, a benzoxazolyl group, a benzoisoxazolyl group, a triazolyl group, a tetrazolyl group, an oxadiazolyl group, a triazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, an imidazopyridinyl group, an imidazopyrimidinyl group, an azacarbazolyl group, an azadibenzofuranyl group, an azadibenzothiophenyl group, an azafluorenyl group, an azadibenzosilolyl group, or a group represented by Formula 91, each unsubstituted or substituted with deuterium, —F, —Cl, —Br, —I, —CD.sub.3, —CD.sub.2H, —CDH.sub.2, —CF.sub.3, —CF.sub.2H, —CFH.sub.2, a hydroxyl group, a cyano group, a nitro group, a C.sub.1-C.sub.20 alkyl group, a C.sub.1-C.sub.20 alkoxy group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, an adamantanyl group, a norbornanyl group, a norbornenyl group, a cyclopentenyl group, a cyclohexenyl group, a cycloheptenyl group, a phenyl group, a biphenyl group, a C.sub.1-C.sub.10 alkylphenyl group, a naphthyl group, a fluorenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a pyrrolyl group, a thiophenyl group, a furanyl group, an imidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolyl group, an isoxazolyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, an isoindolyl group, an indolyl group, an indazolyl group, a purinyl group, a quinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, a cinnolinyl group, a carbazolyl group, a phenanthrolinyl group, a benzimidazolyl group, a benzofuranyl group, a benzothiophenyl group, a benzoisothiazolyl group, a benzoxazolyl group, a benzoisoxazolyl group, a triazolyl group, a tetrazolyl group, an oxadiazolyl group, a triazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, an imidazopyridinyl group, an imidazopyrimidinyl group, or any combination thereof, or

[0300] —C(Q.sub.1)(Q.sub.2)(Q.sub.3) or —Si(Q.sub.1)(Q.sub.2)(Q.sub.3),

[0301] wherein Q.sub.1 to Q.sub.3 may each independently be a phenyl group, a naphthyl group, a pyridinyl group, a pyrimidinyl group, a pyridazinyl group, a pyrazinyl group, or a triazinyl group, each unsubstituted or substituted with deuterium, a C.sub.1-C.sub.10 alkyl group, a phenyl group, a biphenyl group, a pyridinyl group, a pyrimidinyl group, a pyridazinyl group, a pyrazinyl group, a triazinyl group, or any combination thereof,

[0302] in Formulae CY51-16 and CY51-17, i) Y.sub.63 may be O or S, and Y.sub.64 may be Si(R.sub.64a)(R.sub.64b), or ii) Y.sub.63 may be Si(R.sub.63a)(R.sub.63b), and Y.sub.64 may be O or S, and

[0303] in Formulae CY52-16 and CY52-17, i) Y.sub.67 may be O or S, and Y.sub.68 may be Si(R.sub.68a)(R.sub.68b), or ii) Y.sub.67 may be Si(R.sub.67a)(R.sub.67b), and Y.sub.68 may be O or S.

[0304] In Formulae 3-1 to 3-5, L.sub.81 to L.sub.85 may each independently be:

[0305] a single bond; or

[0306] *—C(Q.sub.4)(Q.sub.5)-*′ or *—Si(Q.sub.4)(Q.sub.5)-*′; or

[0307] a benzene group, a naphthalene group, an anthracene group, a phenanthrene group, a triphenylene group, a pyrene group, a chrysene group, a cyclopentadiene group, a furan group, a thiophene group, a silole group, an indene group, a fluorene group, an indole group, a carbazole group, a benzofuran group, a dibenzofuran group, a benzothiophene group, a dibenzothiophene group, a benzosilole group, a dibenzosilole group, an azafluorene group, an azacarbazole group, an azadibenzofuran group, an azadibenzothiophene group, an azadibenzosilole group, a pyridine group, a pyrimidine group, a pyrazine group, a pyridazine group, a triazine group, a quinoline group, an isoquinoline group, a quinoxaline group, a quinazoline group, a phenanthroline group, a pyrrole group, a pyrazole group, an imidazole group, a triazole group, an oxazole group, an isooxazole group, a thiazole group, an isothiazole group, an oxadiazole group, a thiadiazole group, a benzopyrazole group, a benzimidazole group, a benzoxazole group, a benzothiazole group, a benzoxadiazole group, or a benzothiadiazole group, each unsubstituted or substituted with deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, a C.sub.1-C.sub.20 alkyl group, a C.sub.1-C.sub.20 alkoxy group, a phenyl group, a naphthyl group, a pyridinyl group, a pyrimidinyl group, a triazinyl group, a fluorenyl group, a dimethylfluorenyl group, a diphenylfluorenyl group, a carbazolyl group, a phenylcarbazolyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a dibenzosilolyl group, a dimethyldibenzosilolyl group, a diphenyldibenzosilolyl group, —O(Q.sub.31), —S(Q.sub.31), —Si(Q.sub.31)(Q.sub.32)(Q.sub.33), —N(Q.sub.31)(Q.sub.32), —B(Q.sub.31)(Q.sub.32), —P(Q.sub.31)(Q.sub.32), —C(═O)(Q.sub.31), —S(═O).sub.2(Q.sub.31), —P(═O)(Q.sub.31)(Q.sub.32), or any combination thereof,

[0308] wherein Q.sub.4, Q.sub.5, and Q.sub.31 to Q.sub.33 may each independently be hydrogen, deuterium, a C.sub.1-C.sub.20 alkyl group, a C.sub.1-C.sub.20 alkoxy group, a phenyl group, a biphenyl group, a terphenyl group, a pyridinyl group, a pyrimidinyl group, a pyridazinyl group, a pyrazinyl group, or a triazinyl group.

[0309] In embodiments, in Formulae 3-1 and 3-2, a group represented by

##STR00064##

may be represented by one of Formulae CY71-1(1) to CY71-1(8),

[0310] in Formulae 3-1 and 3-3, a group represented by

##STR00065##

may be represented by one of Formulae CY71-2(1) to CY71-2(8),

[0311] in Formulae 3-2 and 3-4, a group represented by

##STR00066##

may be represented by one of Formulae CY71-3(1) to CY71-3(32),

[0312] in Formulae 3-3 to 3-5, a group represented by

##STR00067##

may be represented by one of Formulae CY71-4(1) to CY71-4(32), and/or

[0313] in Formula 3-5, a group represented by

##STR00068##

may be represented by one of Formulae CY71-5(1) to CY71-5(8):

##STR00069## ##STR00070## ##STR00071## ##STR00072## ##STR00073## ##STR00074## ##STR00075## ##STR00076## ##STR00077## ##STR00078## ##STR00079##

[0314] wherein in Formulae CY71-1(1) to CY71-1(8), CY71-2(1) to CY71-2(8), CY71-3(1) to CY71-3(32), CY71-4(1) to CY71-4(32), and CY71-5(1) to CY71-5(8),

[0315] X.sub.81 to X.sub.85, L.sub.81, b81, R.sub.81, and R.sub.85 may respectively be understood by referring to the descriptions of X.sub.81 to X.sub.85, L.sub.81, b81, R.sub.81, and R.sub.85 provided herein,

[0316] X.sub.86 may be a single bond, O, S, N(R.sub.86), B(R.sub.86), C(R.sub.86a)(R.sub.86b), or Si(R.sub.86a)(R.sub.86b),

[0317] X.sub.87 may be a single bond, O, S, N(R.sub.87), B(R.sub.87), C(R.sub.87a)(R.sub.87b), or Si(R.sub.87a)(R.sub.87b),

[0318] in Formulae CY71-1(1) to CY71-1(8) and CY71-4(1) to CY71-4(32), X.sub.86 and X.sub.87 may not be a single bond at the same time,

[0319] X.sub.88 may be a single bond, O, S, N(R.sub.88), B(R.sub.88), C(R.sub.88a)(R.sub.88b), or Si(R.sub.88a)(R.sub.88b),

[0320] X.sub.89 may be a single bond, O, S, N(R.sub.89), B(R.sub.89), C(R.sub.89a)(R.sub.89b), or Si(R.sub.89a)(R.sub.89b),

[0321] in Formulae CY71-2(1) to CY71-2(8), CY71-3(1) to CY71-3(32), and CY71-5(1) to CY71-5(8), X.sub.88 and X.sub.89 may not be a single bond at the same time, and

[0322] R.sub.86 to R.sub.89, R.sub.86a, R.sub.86b, R.sub.87a, R.sub.87b, R.sub.88a, R.sub.88b, R.sub.89a, and R.sub.89b may each independently be the same as defined in connection with R.sub.81 provided herein.

[0323] [Examples of Second Compound, Third Compound, and Fourth Compound]

[0324] In embodiments, the second compound may include at least one of Compounds ETH1 to ETH84:

##STR00080## ##STR00081## ##STR00082## ##STR00083## ##STR00084## ##STR00085## ##STR00086## ##STR00087## ##STR00088## ##STR00089## ##STR00090## ##STR00091## ##STR00092## ##STR00093## ##STR00094## ##STR00095## ##STR00096## ##STR00097##

[0325] In embodiments, the third compound may include at least one of Compounds HTH1 to HTH52:

##STR00098## ##STR00099## ##STR00100## ##STR00101## ##STR00102## ##STR00103## ##STR00104## ##STR00105## ##STR00106## ##STR00107## ##STR00108##

[0326] In embodiments, the fourth compound may include at least one of Compounds DFD1 to DFD12:

##STR00109## ##STR00110## ##STR00111##

[0327] In Compounds ETH1 to ETH84, HTH1 to HTH52, and DFD1 to DFD12, “Ph” represents a phenyl group, “D.sub.5” represents substitution with five deuterium atoms, and “D.sub.4” represents substitution with four deuterium atoms. For example, a group represented by

##STR00112##

may be identical to a group represented by

##STR00113##

[0328] In embodiments, the light-emitting device may satisfy at least one of Conditions 1 to 4:

[0329] [Condition 1]

[0330] LUMO energy level in electron volts (eV) of the third compound >LUMO energy level in electron volts (eV) of the first compound

[0331] [Condition 2]

[0332] LUMO energy level in electron volts (eV) of the first compound >LUMO energy level in electron volts (eV) of the second compound

[0333] [Condition 3]

[0334] HOMO energy level in electron volts (eV) of the first compound >HOMO energy level in electron volts (eV) of the third compound

[0335] [Condition 4]

[0336] HOMO energy level in electron volts (eV) of the third compound >HOMO energy level in electron volts (eV) of the second compound

[0337] The HOMO and LUMO energy levels of the first compound, the second compound, and the third compound may each be a negative value. The HOMO and LUMO energy levels may each be an actual measurement value, or the HOMO and LUMO energy levels may each be a value evaluated according to a density functional theory (DFT) method.

[0338] In embodiments, an absolute value of a difference between the LUMO energy level of the first compound and the LUMO energy level of the second compound may be in a range of about 0.1 eV to about 1.0 eV, an absolute value of a difference between the LUMO energy level of the first compound and the LUMO energy level of the third compound may be in a range of about 0.1 eV to about 1.0 eV, an absolute value of a difference between the HOMO energy level of the first compound and the HOMO energy level of the second compound may be equal to or less than about 1.25 eV (e.g., about 1.25 eV or lower and about 0.2 eV or higher), and an absolute value of a difference between the HOMO energy level of the first compound and the HOMO energy level of the third compound may be equal to or less than about 1.25 eV (e.g., about 1.25 eV or lower and about 0.2 eV or higher).

[0339] When the relationships between LUMO energy level and HOMO energy level satisfy the conditions as described above, a balance between holes and electrons injected into the emission layer may exist.

[0340] The light-emitting device may have a structure of a first embodiment or a second embodiment:

[0341] [Description of First Embodiment]

[0342] According to a first embodiment, the first compound may be included in an emission layer in an interlayer of a light-emitting device, wherein the emission layer may further include a host, the first compound may be different from the host, and the emission layer may emit phosphorescence or fluorescence from the first compound. For example, according to the first embodiment, the first compound may be a dopant or an emitter. In embodiments, the first compound may be a phosphorescent dopant or a phosphorescence emitter.

[0343] Phosphorescence or fluorescence emitted from the first compound may be blue light.

[0344] The emission layer may further include an ancillary dopant. The ancillary dopant may serve to improve luminescence efficiency from the first compound by effectively transferring energy to the first compound as a dopant or an emitter.

[0345] The ancillary dopant may be different from the first compound and the host.

[0346] In embodiments, the ancillary dopant may be a delayed fluorescence-emitting compound.

[0347] In embodiments, the ancillary dopant may be a compound including at least one cyclic group including boron (B) and nitrogen (N) as ring-forming atoms.

[0348] [Description of Second Embodiment]

[0349] According to a second embodiment, the first compound may be included in an emission layer in an interlayer of a light-emitting device, wherein the emission layer may further include a host and a dopant, the first compound may be different from the host and the dopant, and the emission layer may emit phosphorescence or fluorescence (e.g., delayed fluorescence) from the dopant.

[0350] For example, the first compound in the second embodiment may serve as an ancillary dopant that transfers energy to a dopant (or an emitter), and may not serve as a dopant.

[0351] In embodiments, the first compound in the second embodiment may serve as an emitter and as an ancillary dopant that transfers energy to a dopant (or an emitter).

[0352] For example, phosphorescence or fluorescence emitted from the dopant (or the emitter) in the second embodiment may be blue phosphorescence or blue fluorescence (e.g., blue delayed fluorescence).

[0353] The dopant (or the emitter) in the second embodiment may be a phosphorescent dopant material (e.g., the organometallic compound represented by Formula 1, the organometallic compound represented by Formula 401, or any combination thereof) or any fluorescent dopant material (e.g., the compound represented by Formula 501, the compound represented by Formula 502, the compound represented by Formula 503, or any combination thereof).

[0354] In the first embodiment and the second embodiment, the blue light may be blue light having a maximum emission wavelength in a range of about 430 nanometers (nm) to about 490 nm. For example, the blue light may have a maximum emission wavelength in a range of about 430 nm to about 485 nm. For example, the blue light may have a maximum emission wavelength in a range of about 440 nm to about 475 nm. For example, the blue light may have a maximum emission wavelength in a range of about 455 nm to about 470 nm.

[0355] The ancillary dopant in the first embodiment may include, e.g. the fourth compound represented by Formula 502 or Formula 503.

[0356] The host in the first embodiment and the second embodiment may be any host material (e.g., the compound represented by Formula 301, the compound represented by 301-1, the compound represented by Formula 301-2, or any combination thereof).

[0357] In embodiments, the host in the first embodiment and the second embodiment may be the second compound, the third compound, or any combination thereof.

[0358] In embodiments, the light-emitting device may further include at least one of a first capping layer located outside a first electrode and a second capping layer located outside a second electrode, and at least one of the first capping layer and the second capping layer may include the organometallic compound represented by Formula 1. The first capping layer and the second capping layer may respectively be understood by referring to the descriptions of the first capping layer and the second capping layer provided herein.

[0359] In embodiments, the light-emitting device may include: a first capping layer located outside the first electrode and including the organometallic compound represented by Formula 1; a second capping layer located outside the second electrode and including the organometallic compound represented by Formula 1; or the first capping layer and the second capping layer.

[0360] The expression that an “(interlayer and/or a capping layer) includes at least one organometallic compound represented by Formula 1” as used herein may be construed as meaning that the “(interlayer and/or the capping layer) may include one organometallic compound of Formula 1 or two different organometallic compounds of Formula 1”.

[0361] For example, the interlayer and/or the capping layer may include Compound D1 only as the organometallic compound. In this embodiment, Compound D1 may be included in the emission layer of the light-emitting device. In embodiments, Compounds D1 and D2 may be included in the interlayer as organometallic compounds. In this embodiment, Compounds D1 and D2 may be included in the same layer (for example, both Compounds D1 and D2 may be included in an emission layer) or in different layers (for example, Compound D1 may be included in an emission layer, and Compound D2 may be included in an electron transport region).

[0362] The term “interlayer” as used herein refers to a single layer or multiple layers located between a first electrode and a second electrode in a light-emitting device.

[0363] According to embodiments, an electronic apparatus may include the light-emitting device. The electronic apparatus may further include a thin-film transistor. In embodiments, the electronic apparatus may further include a thin-film transistor including a source electrode and drain electrode, and a first electrode of the light-emitting device may be electrically connected to the source electrode or the drain electrode. In an embodiment, the electronic apparatus may further include a color filter, a color-conversion layer, a touchscreen layer, a polarization layer, or any combination thereof. The electronic apparatus may be understood by referring to the description of the electronic apparatus provided herein.

[0364] [Description of FIG. 1]

[0365] FIG. 1 is a schematic cross-sectional view of a light-emitting device 10 according to an embodiment. The light-emitting device 10 may include a first electrode 110, an interlayer 130, and a second electrode 150.

[0366] Hereinafter, the structure of the light-emitting device 10 according to an embodiment and a method of manufacturing the light-emitting device 10 according to an embodiment will be described in connection with FIG. 1.

[0367] [First Electrode 110]

[0368] In FIG. 1, a substrate may be further included under the first electrode 110 or above the second electrode 150. The substrate may be a glass substrate or a plastic substrate. The substrate may be a flexible substrate including plastic having excellent heat resistance and durability, for example, polyimide, polyethylene terephthalate (PET), polycarbonate, polyethylene naphthalate, polyarylate (PAR), polyetherimide, or any combination thereof.

[0369] The first electrode 110 may be formed by depositing or sputtering, on the substrate, a material for forming the first electrode 110. When the first electrode 110 is an anode, a high work function material that may easily inject holes may be used as a material for a first electrode 110.

[0370] The first electrode 110 may be a reflective electrode, a transflective electrode, or a transmissive electrode. When the first electrode 110 is a transmissive electrode, a material for forming the first electrode 110 may be indium tin oxide (ITO), indium zinc oxide (IZO), tin oxide (SnO.sub.2), zinc oxide (ZnO), or any combinations thereof. In embodiments, when the first electrode 110 is a transflective electrode or a reflective electrode, magnesium (Mg), silver (Ag), aluminum (Al), aluminum-lithium (Al—Li), calcium (Ca), magnesium-indium (Mg—In), magnesium-silver (Mg—Ag), or any combination thereof may be used as a material for forming the first electrode 110.

[0371] The first electrode 110 may have a structure consisting of a single layer or a structure including two or more layers. In embodiments, the first electrode 110 may have a triple-layered structure of ITO/Ag/ITO.

[0372] [Interlayer 130]

[0373] The interlayer 130 may be on the first electrode 110. The interlayer 130 may include an emission layer.

[0374] The interlayer 130 may further include a hole transport region between the first electrode 110 and the emission layer and an electron transport region between the emission layer and the second electrode 150.

[0375] The interlayer 130 may further include metal-containing compounds such as organometallic compounds, inorganic materials such as quantum dots, and the like, in addition to various organic materials.

[0376] The interlayer 130 may include at least two emitting units sequentially stacked between the first electrode 110 and the second electrode 150; and a charge generation layer between the at least two emitting units. When the interlayer 130 includes the at least two emitting units and a charge generation layer, the light-emitting device 10 may be a tandem light-emitting device.

[0377] [Hole transport region in interlayer 130]

[0378] The hole transport region may have a structure consisting of a layer consisting of a single material, a structure consisting of a layer including different materials, or a multi-layered structure having layers including a plurality of different materials.

[0379] The hole transport region may include a hole injection layer, a hole transport layer, an emission auxiliary layer, an electron blocking layer, or a combination thereof.

[0380] For example, the hole transport region may have a multi-layered structure, e.g., a hole injection layer/hole transport layer structure, a hole injection layer/hole transport layer/emission auxiliary layer structure, a hole injection layer/emission auxiliary layer structure, a hole transport layer/emission auxiliary layer structure, or a hole injection layer/hole transport layer/electron blocking layer structure, wherein layers of each structure may be stacked on the first electrode 110 in its respective stated order, but embodiments are not limited thereto.

[0381] The hole transport region may include the compound represented by Formula 201, the compound represented by Formula 202, or any combination thereof:

##STR00114##

[0382] In Formulae 201 and 202,

[0383] L.sub.201 to L.sub.204 may each independently be a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a,

[0384] L.sub.205 may be *—O—*′, *—S—*′, *—N(Q.sub.201)-*′, a C.sub.1-C.sub.20 alkylene group unsubstituted or substituted with at least one R.sub.10a, a C.sub.2-C.sub.20 alkenylene group unsubstituted or substituted with at least one R.sub.10a, a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a, or a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a, and * and each indicate a binding site to a neighboring atom,

[0385] xa1 to xa4 may each independently be an integer from 0 to 5,

[0386] xa5 may be an integer from 1 to 10,

[0387] R.sub.201 to R.sub.204 and Q.sub.201 may each independently be a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a,

[0388] R.sub.201 and R.sub.202 may optionally be bound to each other via a single bond, a C.sub.1-C.sub.5 alkylene group unsubstituted or substituted with at least one R.sub.10a, or a C.sub.2-C.sub.5 alkenylene group unsubstituted or substituted with at least one R.sub.10a to form a C.sub.8-C.sub.60 polycyclic group (e.g., a carbazole group or the like) unsubstituted or substituted with at least one R.sub.10a (e.g., Compound HT16 described herein),

[0389] R.sub.203 and R.sub.204 may optionally be bound to each other via a single bond, a C.sub.1-C.sub.5 alkylene group unsubstituted or substituted with at least one R.sub.10a, or a C.sub.2-C.sub.5 alkenylene group unsubstituted or substituted with at least one R.sub.10a to form a C.sub.8-C.sub.60 polycyclic group unsubstituted or substituted with at least one R.sub.10a, and R.sub.10a may be understood by referring to the description of R.sub.10a provided herein, and

[0390] na1 may be an integer from 1 to 4.

[0391] In embodiments, Formulae 201 and 202 may each include at least one of groups represented by Formulae CY201 to CY217:

##STR00115## ##STR00116##

[0392] In Formulae CY201 to CY217, R.sub.10b and R.sub.10c may each independently be the same as described in connection with R.sub.10a, ring CY.sub.201 to ring CY.sub.204 may each independently be a C.sub.3-C.sub.20 carbocyclic group or a C.sub.1-C.sub.20 heterocyclic group, and at least one hydrogen in Formulae CY201 to CY217 may be unsubstituted or substituted with R.sub.10a.

[0393] In embodiments, in Formulae CY201 to CY217, ring CY.sub.201 to ring CY.sub.204 may each independently be a benzene group, a naphthalene group, a phenanthrene group, or an anthracene group.

[0394] In embodiments, Formulae 201 and 202 may each include at least one of groups represented by Formulae CY201 to CY203.

[0395] In embodiments, Formula 201 may include at least one of groups represented by Formulae CY201 to CY203 and at least one of groups represented by Formulae CY204 to CY217.

[0396] In embodiments, in Formula 201, xa1 may be 1, R.sub.201 may be a group represented by any one of Formulae CY201 to CY203, xa2 may be 0, and R.sub.202 may be a group represented by any one of Formulae CY204 to CY207.

[0397] In embodiments, Formulae 201 and 202 may each not include groups represented by Formulae CY201 to CY203.

[0398] In embodiments, Formulae 201 and 202 may each not include groups represented by Formulae CY201 to CY203, and include at least one of groups represented by Formulae CY204 to CY217.

[0399] In embodiments, Formulae 201 and 202 may each not include groups represented by Formulae CY201 to CY217.

[0400] In embodiments, the hole transport region may include one of Compounds HT1 to HT46 and m-MTDATA, TDATA, 2-TNATA, NPB (NPD), β-NPB, TPD, spiro-TPD, spiro-NPB, methylated-NPB, TAPC, HMTPD, 4,4′,4″-tris(N-carbazolyl)triphenylamine (TCTA), polyaniline/dodecylbenzenesulfonic acid (PANI/DBSA), poly(3,4-ethylenedioxythiophene)/poly(4-styrenesulfonate) (PEDOT/PSS), polyaniline/camphorsulfonic acid (PANI/CSA), polyaniline/poly(4-styrenesulfonate (PANI/PSS), or any combination thereof:

##STR00117## ##STR00118## ##STR00119## ##STR00120## ##STR00121## ##STR00122## ##STR00123## ##STR00124## ##STR00125## ##STR00126##

[0401] A thickness of the hole transport region may be in a range of about 50 Angstroms (Å) to about 10,000 Å. For example, the thickness of the hole transport region may be in a range of about 100 Å to about 4,000 Å. When the hole transport region includes a hole injection layer, a hole transport layer, or any combination thereof, a thickness of the hole injection layer may be in a range of about 100 Å to about 9,000 Å, and a thickness of the hole transport layer may be in a range of about 50 Å to about 2,000 Å. For example, the thickness of the hole injection layer may be in a range of 100 Å to about 1,000 Å. For example, the thickness of the hole transport layer may be in a range of about 100 Å to about 1,500 Å. When the thicknesses of the hole transport region, the hole injection layer, and the hole transport layer are within any of these ranges, excellent hole transport characteristics may be obtained without a substantial increase in driving voltage.

[0402] The emission auxiliary layer may increase luminescence efficiency by compensating for an optical resonance distance according to a wavelength of light emitted by an emission layer. The electron blocking layer may prevent leakage of electrons to a hole transport region from the emission layer. Materials that may be included in the hole transport region may also be included in an emission auxiliary layer and an electron blocking layer.

[0403] [p-Dopant]

[0404] The hole transport region may include a charge generating material as well as the aforementioned materials to improve conductive properties of the hole transport region. The charge generating material may be substantially homogeneously or non-homogeneously dispersed (for example, as a single layer consisting of charge generating material) in the hole transport region.

[0405] The charge generating material may include, for example, a p-dopant.

[0406] In embodiments, a lowest unoccupied molecular orbital (LUMO) energy level of the p-dopant may be equal to or less than about −3.5 eV.

[0407] In embodiments, the p-dopant may include a quinone derivative, a compound containing a cyano group, a compound containing element EL1 and element EL2, or any combination thereof.

[0408] Examples of the quinone derivative may include TCNQ, F4-TCNQ, and the like.

[0409] Examples of the compound containing a cyano group include HAT-CN, a compound represented by Formula 221, and the like:

##STR00127##

[0410] In Formula 221,

[0411] R.sub.221 to R.sub.223 may each independently be a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a, and

[0412] at least one of R.sub.221 to R.sub.223 may each independently be: a C.sub.3-C.sub.60 carbocyclic group or a C.sub.1-C.sub.60 heterocyclic group, substituted with a cyano group; —F; —Cl; —Br; —I; a C.sub.1-C.sub.20 alkyl group substituted with a cyano group, —F, —Cl, —Br, —I, or any combination thereof; or any combination thereof.

[0413] In the compound containing element EL1 and element EL2, element EL1 may be a metal, a metalloid, or a combination thereof, and element EL2 may be a non-metal, a metalloid, or a combination thereof.

[0414] Examples of the metal may include an alkali metal (e.g., lithium (Li), sodium (Na), potassium (K), rubidium (Rb), cesium (Cs), or the like); an alkaline earth metal (e.g., beryllium (Be), magnesium (Mg), calcium (Ca), strontium (Sr), barium (Ba), or the like); a transition metal (e.g., titanium (Ti), zirconium (Zr), hafnium (Hf), vanadium (V), niobium (Nb), tantalum (Ta), chromium (Cr), molybdenum (Mo), tungsten (W), manganese (Mn), technetium (Tc), rhenium (Re), iron (Fe), ruthenium (Ru), osmium (Os), cobalt (Co), rhodium (Rh), iridium (Ir), nickel (Ni), palladium (Pd), platinum (Pt), copper (Cu), silver (Ag), gold (Au), or the like); a post-transition metal (e.g., zinc (Zn), indium (In), tin (Sn), or the like); a lanthanide metal (e.g., lanthanum (La), cerium (Ce), praseodymium (Pr), neodymium (Nd), promethium (Pm), samarium (Sm), europium (Eu), gadolinium (Gd), terbium (Tb), dysprosium (Dy), holmium (Ho), erbium (Er), thulium (Tm), ytterbium (Yb), lutetium (Lu), or the like); and the like.

[0415] Examples of the metalloid may include silicon (Si), antimony (Sb), tellurium (Te), and the like.

[0416] Examples of the non-metal may include oxygen (O), a halogen (e.g., F, Cl, Br, I, and the like), and the like.

[0417] For example, the compound containing element EL1 and element EL2 may include a metal oxide, a metal halide (e.g., metal fluoride, metal chloride, metal bromide, metal iodide, and the like), a metalloid halide (e.g., a metalloid fluoride, a metalloid chloride, a metalloid bromide, a metalloid iodide, and the like), a metal telluride, or any combination thereof.

[0418] Examples of the metal oxide may include tungsten oxide (e.g., WO, W.sub.2O.sub.3, WO.sub.2, WO.sub.3, W.sub.2O.sub.5, and the like), vanadium oxide (e.g., VO, V.sub.2O.sub.3, VO.sub.2, V.sub.2O.sub.5, and the like), molybdenum oxide (e.g., MoO, Mo.sub.2O.sub.3, MoO.sub.2, MoO.sub.3, Mo.sub.2O.sub.5, and the like), rhenium oxide (e.g., ReO.sub.3 and the like), and the like.

[0419] Examples of the metal halide may include an alkali metal halide, an alkaline earth metal halide, a transition metal halide, a post-transition metal halide, a lanthanide metal halide, and the like.

[0420] Examples of the alkali metal halide may include LiF, NaF, KF, RbF, CsF, LiCl, NaCl, KCl, RbCl, CsCl, LiBr, NaBr, KBr, RbBr, CsBr, LiI, NaI, KI, RbI, CsI, and the like.

[0421] Examples of the alkaline earth metal halide may include BeF.sub.2, MgF.sub.2, CaF.sub.2, SrF.sub.2, BaF.sub.2, BeCl.sub.2, MgCl.sub.2, CaCl.sub.2), SrCl.sub.2, BaCl.sub.2, BeBr.sub.2, MgBr.sub.2, CaBr.sub.2, SrBr.sub.2, BaBr.sub.2, BeI.sub.2, MgI.sub.2, CaI.sub.2, SrI.sub.2, BaI.sub.2, and the like.

[0422] Examples of the transition metal halide may include titanium halide (e.g., TiF.sub.4, TiCl.sub.4, TiBr.sub.4, TiI.sub.4, and the like), zirconium halide (e.g., ZrF.sub.4, ZrCl.sub.4, ZrBr.sub.4, ZrI.sub.4, and the like), hafnium halide (e.g., HfF.sub.4, HfCl.sub.4, HfBr.sub.4, Hff.sub.4, and the like), vanadium halide (e.g., VF.sub.3, VCl.sub.3, VBr.sub.3, VI.sub.3, and the like), niobium halide (e.g., NbF.sub.3, NbCl.sub.3, NbBr.sub.3, NbI.sub.3, and the like), tantalum halide (e.g., TaF.sub.3, TaCl.sub.3, TaBr.sub.3, TaI.sub.3, and the like), chromium halide (e.g., CrF.sub.3, CrCl.sub.3, CrBr.sub.3, CrI.sub.3, and the like), molybdenum halide (e.g., MoF.sub.3, MoCl.sub.3, MoBr.sub.3, MoI.sub.3, and the like), tungsten halide (e.g., WF.sub.3, WCl.sub.3, WBr.sub.3, WI.sub.3, and the like), manganese halide (e.g., MnF.sub.2, MnCl.sub.2, MnBr.sub.2, MnI.sub.2, and the like), technetium halide (e.g., TcF.sub.2, TcCl.sub.2, TcBr.sub.2, TcJ.sub.2, and the like), rhenium halide (e.g., ReF.sub.2, ReCl.sub.2, ReBr.sub.2, ReI.sub.2, and the like), iron halide (e.g., FeF.sub.2, FeCl.sub.2, FeBr.sub.2, FeI.sub.2, and the like), ruthenium halide (e.g., RuF.sub.2, RuCl.sub.2, RuBr.sub.2, RuI.sub.2, and the like), osmium halide (e.g., OsF.sub.2, OsCl.sub.2, OsBr.sub.2, OsI.sub.2, and the like), cobalt halide (e.g., CoF.sub.2, CoCl.sub.2, CoBr.sub.2, Cob.sub.2, and the like), rhodium halide (e.g., RhF.sub.2, RhCl.sub.2, RhBr.sub.2, RhJ.sub.2, and the like), iridium halide (e.g., IrF.sub.2, IrCl.sub.2, IrBr.sub.2, IrI.sub.2, and the like), nickel halide (e.g., NiF.sub.2, NiCl.sub.2, NiBr.sub.2, NiI.sub.2, and the like), palladium halide (e.g., PdF.sub.2, PdCl.sub.2, PdBr.sub.2, PdI.sub.2, and the like), platinum halide (e.g., PtF.sub.2, PtCl.sub.2, PtBr.sub.2, PtI.sub.2, and the like), copper halide (e.g., CuF, CuCl, CuBr, CuI, and the like), silver halide (e.g., AgF, AgCl, AgBr, AgI, and the like), gold halide (e.g., AuF, AuCl, AuBr, AuI, and the like), and the like.

[0423] Examples of the post-transition metal halide may include zinc halide (e.g., ZnF.sub.2, ZnCl.sub.2, ZnBr.sub.2, ZnI.sub.2, and the like), indium halide (e.g., InI.sub.3 and the like), tin halide (e.g., SnI.sub.2 and the like), and the like.

[0424] Examples of the lanthanide metal halide may include YbF, YbF.sub.2, YbF.sub.3, SmF.sub.3, YbCl, YbCl.sub.2, YbCl.sub.3, SmCl.sub.3, YbBr, YbBr.sub.2, YbBr.sub.3, SmBr.sub.3, YbI, YbI.sub.2, YbI.sub.3, SmI.sub.3, and the like.

[0425] Examples of the metalloid halide may include antimony halide (e.g., SbCl.sub.5 and the like) and the like.

[0426] Examples of the metal telluride may include an alkali metal telluride (e.g., Li.sub.2Te, Na.sub.2Te, K.sub.2Te, Rb.sub.2Te, Cs.sub.2Te, and the like), an alkaline earth metal telluride (e.g., BeTe, MgTe, CaTe, SrTe, BaTe, and the like), a transition metal telluride (e.g., TiTe.sub.2, ZrTe.sub.2, HfTe.sub.2, V.sub.2Te.sub.3, Nb.sub.2Te.sub.3, Ta.sub.2Te.sub.3, Cr.sub.2Te.sub.3, Mo.sub.2Te.sub.3, W.sub.2Te.sub.3, MnTe, TcTe, ReTe, FeTe, RuTe, OsTe, CoTe, RhTe, IrTe, NiTe, PdTe, PtTe, Cu.sub.2Te, CuTe, Ag.sub.2Te, AgTe, Au.sub.2Te, and the like), a post-transition metal telluride (e.g., ZnTe and the like), a lanthanide metal telluride (e.g., LaTe, CeTe, PrTe, NdTe, PmTe, EuTe, GdTe, TbTe, DyTe, HoTe, ErTe, TmTe, YbTe, LuTe, and the like), and the like.

[0427] [Emission Layer in Interlayer 130]

[0428] When the light-emitting device 10 is a full color light-emitting device, the emission layer may be patterned into a red emission layer, a green emission layer, and/or a blue emission layer, according to a subpixel. In embodiments, the emission layer may have a stacked structure. The stacked structure may include two or more layers selected from a red emission layer, a green emission layer, and a blue emission layer. The two or more layers may directly contact each other. In embodiments, the two or more layers may be separated from each other. In embodiments, the emission layer may include two or more materials. The two or more materials may include a red light-emitting material, a green light-emitting material, or a blue light-emitting material. The two or more materials may be mixed with each other in a single layer. The two or more materials mixed with each other in the single layer may emit white light.

[0429] The emission layer may include a host and a dopant. The dopant may be a phosphorescent dopant, a fluorescent dopant, or any combination thereof.

[0430] An amount of the dopant in the emission layer may be in a range of about 0.01 parts to about 15 parts by weight based on 100 parts by weight of the host.

[0431] In embodiments, the emission layer may include a quantum dot.

[0432] The emission layer may include a delayed fluorescence material. The delayed fluorescence material may serve as a host or a dopant in the emission layer.

[0433] A thickness of the emission layer may be in a range of about 100 Å to about 1,000 Å. In embodiments, the thickness of the emission layer may be in a range of about 200 Å to about 600 Å. When the thickness of the emission layer is within any of these ranges, improved luminescence characteristics may be obtained without a substantial increase in driving voltage.

[0434] [Host]

[0435] The host may include a compound represented by Formula 301:

[Ar.sub.301].sub.xb11-[(L.sub.301).sub.xb1-R.sub.301].sub.xb21  [Formula 301]

[0436] In Formula 301,

[0437] Ar.sub.3O.sub.1 and L.sub.301 may each independently be a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a,

[0438] xb11 may be 1, 2, or 3,

[0439] xb1 may be an integer from 0 to 5,

[0440] R.sub.301 may be hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, a C.sub.1-C.sub.60 alkyl group unsubstituted or substituted with at least one R.sub.10a, a C.sub.2-C.sub.60 alkenyl group unsubstituted or substituted with at least one R.sub.10a, a C.sub.2-C.sub.60 alkynyl group unsubstituted or substituted with at least one R.sub.10a, a C.sub.1-C.sub.60 alkoxy group unsubstituted or substituted with at least one R.sub.10a, a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a, a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a, —Si(Q.sub.301)(Q.sub.302)(Q.sub.303), —N(Q.sub.301)(Q.sub.302), —B(Q.sub.301)(Q.sub.302), —C(═O)(Q.sub.301), —S(═O).sub.2(Q.sub.301), or —P(═O)(Q.sub.301)(Q.sub.302), and R.sub.10a may be understood by referring to the description of R.sub.10a provided herein,

[0441] xb21 may be an integer from 1 to 5, and

[0442] Q.sub.301 to Q.sub.303 may independently each be understood by referring to the description of Q.sub.1 provided herein.

[0443] In embodiments, when xb11 in Formula 301 is 2 or greater, at least two Ar.sub.3O.sub.1(s) may be bound via a single bond.

[0444] In embodiments, the host may include a compound represented by Formula 301-1, a compound represented by Formula 301-2, or any combination thereof:

##STR00128##

[0445] In Formulae 301-1 and 301-2,

[0446] ring A.sub.301 to ring A.sub.304 may each independently be a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a, and R.sub.10a may be understood by referring to the description of R.sub.10a provided herein,

[0447] X.sub.301 may be O, S, N-[(L.sub.304).sub.xb4-R.sub.304], C(R.sub.304)(R.sub.305), or Si(R.sub.304)(R.sub.305),

[0448] xb22 and xb23 may each independently be 0, 1, or 2,

[0449] L.sub.301, xb1, and R.sub.301 may respectively be understood by referring to the descriptions of L.sub.301, xb1, and R.sub.301 provided herein,

[0450] L.sub.302 to L.sub.304 may each independently be understood by referring to the description of L.sub.301 provided herein,

[0451] xb2 to xb4 may each independently be understood by referring to the description of xb1 provided herein, and

[0452] R.sub.302 to R.sub.305 and R.sub.311 to R.sub.314 may each independently be understood by referring to the description of R.sub.301 provided herein.

[0453] In embodiments, the host may include an alkaline earth-metal complex, a post-transitional metal complex, or any combination thereof. For example, the host may include a Be complex (e.g., Compound H55), a Mg complex, a Zn complex, or any combination thereof.

[0454] In embodiments, the host may include one of Compounds H1 to H124, 9,10-di(2-naphthyl)anthracene (ADN), 2-methyl-9,10-bis(naphthalen-2-yl)anthracene (MADN), 9,10-di-(2-naphthyl)-2-t-butyl-anthracene (TBADN), 4,4′-bis(N-carbazolyl)-1,1′-biphenyl (CBP), 1,3-di-9-carbazolylbenzene (mCP), 1,3,5-tri(carbazol-9-yl)benzene (TCP), or any combination thereof:

##STR00129## ##STR00130## ##STR00131## ##STR00132## ##STR00133## ##STR00134## ##STR00135## ##STR00136## ##STR00137## ##STR00138## ##STR00139## ##STR00140## ##STR00141## ##STR00142## ##STR00143## ##STR00144## ##STR00145## ##STR00146## ##STR00147## ##STR00148## ##STR00149## ##STR00150## ##STR00151## ##STR00152## ##STR00153## ##STR00154## ##STR00155## ##STR00156##

[0455] [Phosphorescent Dopant]

[0456] The phosphorescent dopant may include the organometallic compound represented by Formula 1.

[0457] In embodiments, the phosphorescent dopant may include at least one transition metal as a center metal.

[0458] The phosphorescent dopant may include a monodentate ligand, a bidentate ligand, a tridentate ligand, a tetradentate ligand, a pentadentate ligand, a hexadentate ligand, or any combination thereof.

[0459] The phosphorescent dopant may be electrically neutral.

[0460] In embodiments, the phosphorescent dopant may include an organometallic complex represented by Formula 401:

##STR00157##

[0461] In Formulae 401 and 402,

[0462] M may be transition metal (e.g., iridium (Ir), platinum (Pt), palladium (Pd), osmium (Os), titanium (Ti), gold (Au), hafnium (Hf), europium (Eu), terbium (Tb), rhodium (Rh), rhenium (Re), or thulium (Tm)),

[0463] L.sub.401 may be a ligand represented by Formula 402, and xc1 may be 1, 2, or 3, and when xc1 is 2 or greater, at least two L.sub.4O.sub.1(s) may be identical to or different from each other,

[0464] L.sub.402 may be an organic ligand, and xc2 may be an integer from 0 to 4, and when xc2 is 2 or greater, at least two L.sub.4O.sub.2(s) may be identical to or different from each other,

[0465] X.sub.401 and X.sub.4O.sub.2 may each independently be nitrogen (N) or carbon (C),

[0466] ring A.sub.401 and ring A.sub.402 may each independently be a C.sub.3-C.sub.60 carbocyclic group or a C.sub.1-C.sub.60 heterocyclic group,

[0467] T.sub.401 may be a single bond, *—O—*′, *—S—*′, *—C(═O)—*′, *—N(Q.sub.41)-*′, *—C(Q.sub.411)(Q.sub.412)-*′, *—C(Q.sub.411)=C(Q.sub.412)-*′, *—C(Q.sub.411)=*′, or *═C═*′,

[0468] X.sub.403 and X.sub.4O.sub.4 may each independently be a chemical bond (e.g., a covalent bond or a coordinate bond), O, S, N(Q.sub.413), B(Q.sub.413), P(Q.sub.413), C(Q.sub.413)(Q.sub.414), or Si(Q.sub.413)(Q.sub.414), and * and each indicate a binding site to a neighboring atom,

[0469] Q.sub.411 to Q.sub.414 may each independently be understood by referring to the description of Q.sub.1 provided herein,

[0470] R.sub.401 and R.sub.402 may each independently be hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, a C.sub.1-C.sub.20 alkyl group unsubstituted or substituted with at least one R.sub.10a, a C.sub.1-C.sub.20 alkoxy group unsubstituted or substituted with at least one R.sub.10a, a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a, a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a, —Si(Q.sub.401)(Q.sub.402)(Q.sub.403), —N(Q.sub.401)(Q.sub.402), —B(Q.sub.401)(Q.sub.402), —C(═O)(Q.sub.401), —S(═O).sub.2(Q.sub.401), or —P(═O)(Q.sub.401)(Q.sub.402), and R.sub.10a may be understood by referring to the description of R.sub.10a provided herein,

[0471] Q.sub.401 to Q.sub.403 may each independently be understood by referring to the description of Q.sub.1 provided herein,

[0472] xc11 and xc12 may each independently be an integer from 0 to 10, and

[0473] * and *′ in Formula 402 each indicate a binding site to M in Formula 401.

[0474] In embodiments, in Formula 402, X.sub.401 may be nitrogen and X.sub.402 may be carbon, or X.sub.401 and X.sub.402 may both be nitrogen.

[0475] In embodiments, when xc1 in Formula 401 is 2 or greater, two ring A.sub.401(s) of at least two L.sub.401(s) may optionally be bound via T.sub.402 as a linking group, or two ring A.sub.402(s) may optionally be bound via T.sub.403 as a linking group (see Compounds PD1 to PD4 and PD7). T.sub.402 and T.sub.403 may each independently be understood by referring to the description of T.sub.401 provided herein.

[0476] L.sub.402 in Formula 401 may be any suitable organic ligand. For example, L.sub.402 may be a halogen group, a diketone group (e.g., an acetylacetonate group), a carboxylic acid group (e.g., a picolinate group), —C(═O), an isonitrile group, —CN, or a phosphorus group (e.g., a phosphine group or a phosphite group).

[0477] The phosphorescent dopant may be, for example, one of Compounds PD1 to PD25 or any combination thereof.

##STR00158## ##STR00159## ##STR00160## ##STR00161## ##STR00162## ##STR00163## ##STR00164##

[0478] [Fluorescent Dopant]

[0479] The fluorescent dopant may include an amine group-containing compound, a styryl group-containing compound, or any combination thereof.

[0480] In embodiments, the fluorescent dopant may include a compound represented by Formula 501:

##STR00165##

[0481] In Formula 501,

[0482] Ar.sub.501, L.sub.501 to L.sub.503, R.sub.501, and R.sub.502 may each independently be a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a,

[0483] xd1 to xd3 may each independently be 0, 1, 2, or 3, and

[0484] xd4 may be 1, 2, 3, 4, 5, or 6.

[0485] In embodiments, in Formula 501, Ar.sub.50i may include a condensed ring group (e.g., an anthracene group, a chrysene group, or a pyrene group) in which at least three monocyclic groups are condensed.

[0486] In embodiments, xd4 in Formula 501 may be 2.

[0487] In embodiments, the fluorescent dopant may include one of Compounds FD1 to FD36, DPVBi, DPAVBi, or any combination thereof.

##STR00166## ##STR00167## ##STR00168## ##STR00169## ##STR00170## ##STR00171## ##STR00172##

[0488] [Delayed Fluorescence Material]

[0489] The emission layer may include a delayed fluorescence material.

[0490] The delayed fluorescence material described herein may be any suitable compound that may emit delayed fluorescence according to a delayed fluorescence emission mechanism.

[0491] The delayed fluorescence material included in the emission layer may serve as a host or a dopant, depending on types of other materials included in the emission layer.

[0492] In embodiments, a difference between a triplet energy level in electron volts (eV) of the delayed fluorescence material and a singlet energy level in electron volts (eV) of the delayed fluorescence material may be in a range of about 0 eV to about 0.5 eV. When the difference between a triplet energy level in electron volts (eV) of the delayed fluorescence material and a singlet energy level in electron volts (eV) of the delayed fluorescence material is within this range, up-conversion from a triplet state to a singlet state in the delayed fluorescence material may effectively occur, thus improving luminescence efficiency and the like of the light-emitting device 10.

[0493] In embodiments, the delayed fluorescence material may include: a material including at least one electron donor (e.g., a π electron-rich C.sub.3-C.sub.60 cyclic group such as a carbazole group and the like) and at least one electron acceptor (e.g., a sulfoxide group, a cyano group, a π electron-deficient nitrogen-containing C.sub.1-C.sub.60 cyclic group, and the like), a material including a C.sub.8-C.sub.60 polycyclic group including at least two cyclic groups condensed to each other and sharing boron (B), and the like.

[0494] Examples of the delayed fluorescence material may include at least one of Compounds DF1 to DF9:

##STR00173##

[0495] [Quantum Dots]

[0496] The emission layer may include quantum dots.

[0497] The term “quantum dot” as used herein may be a crystal of a semiconductor compound and may include any suitable material capable of emitting emission wavelengths of various lengths according to the size of the crystal.

[0498] A diameter of the quantum dot may be, for example, in a range of about 1 nm to about 10 nm.

[0499] Quantum dots may be synthesized by a wet chemical process, a metal organic chemical vapor deposition process, a molecular beam epitaxy process, or any similar process.

[0500] The wet chemical process is a method of growing a quantum dot particle crystal by mixing a precursor material with an organic solvent. When the crystal grows, the organic solvent may naturally serve as a dispersant coordinated on the surface of the quantum dot crystal and control the growth of the crystal. Thus, the wet chemical method may be easier to perform than the vapor deposition process such a metal organic chemical vapor deposition (MOCVD) or a molecular beam epitaxy (MBE) process. Further, the growth of quantum dot particles may be controlled with a lower manufacturing cost.

[0501] The quantum dot may include a Group II-VI semiconductor compound; a Group III-V semiconductor compound; a Group III-VI semiconductor compound; a Group I-III-VI semiconductor compound; a Group IV-VI semiconductor compound; a Group IV element or compound; or any combination thereof.

[0502] Examples of the Group II-VI semiconductor compound may include a binary compound such as CdS, CdSe, CdTe, ZnS, ZnSe, ZnTe, ZnO, HgS, HgSe, HgTe, MgSe, or MgS; a ternary compound such as CdSeS, CdSeTe, CdSTe, ZnSeS, ZnSeTe, ZnSTe, HgSeS, HgSeTe, HgSTe, CdZnS, CdZnSe, CdZnTe, CdHgS, CdHgSe, CdHgTe, HgZnS, HgZnSe, HgZnTe, MgZnSe, or MgZnS; a quaternary compound such as CdZnSeS, CdZnSeTe, CdZnSTe, CdHgSeS, CdHgSeTe, CdHgSTe, HgZnSeS, HgZnSeTe, or HgZnSTe; or any combination thereof.

[0503] Examples of the Group III-V semiconductor compound may include a binary compound such as GaN, GaP, GaAs, GaSb, AlN, AlP, AlAs, AlSb, InN, InP, InAs, or InSb; a ternary compound such as GaNP, GaNAs, GaNSb, GaPAs, GaPSb, AlNP, AlNAs, AlNSb, AlPAs, AlPSb, InGaP, InNP, InAIP, InNAs, InNSb, InPAs, or InPSb; a quaternary compound such as GaAlNP, GaAlNAs, GaAlNSb, GaAlPAs, GaAlPSb, GaInNP, GaInNAs, GaInNSb, GaInPAs, GaInPSb, InAlNP, InAlNAs, InAlNSb, InAlPAs, or InAlPSb; or any combination thereof. In embodiments, the Group III-V semiconductor compound may further include a Group II element. Examples of the Group III-V semiconductor compound further including a Group II element may include InZnP, InGaZnP, InAlZnP, and the like.

[0504] Examples of the Group III-VI semiconductor compound may include a binary compound such as GaS, GaSe, Ga.sub.2Se.sub.3, GaTe, InS, InSe, In.sub.2S.sub.3, In.sub.2Se.sub.3, InTe, and the like; a ternary compound such as InGaS.sub.3, InGaSe.sub.3, and the like; or any combination thereof.

[0505] Examples of the Group I-III-VI semiconductor compound may include a ternary compound such as AgInS, AgInS.sub.2, CuInS, CuInS.sub.2, CuGaO.sub.2, AgGaO.sub.2, AgAlO.sub.2, or any combination thereof.

[0506] Examples of the Group IV-VI semiconductor compound may include a binary compound such as SnS, SnSe, SnTe, PbS, PbSe, or PbTe; a ternary compound such as SnSeS, SnSeTe, SnSTe, PbSeS, PbSeTe, PbSTe, SnPbS, SnPbSe, or SnPbTe; a quaternary compound such as SnPbSSe, SnPbSeTe, or SnPbSTe; or any combination thereof.

[0507] The Group IV element or compound may be a single element material such as Si or Ge; a binary compound such as SiC or SiGe; or any combination thereof.

[0508] Individual elements included in the multi-element compound, such as a binary compound, a ternary compound, and a quaternary compound, may be present in a particle thereof at a uniform or at a non-uniform concentration.

[0509] The quantum dot may have a single structure in which the concentration of each element included in the quantum dot is uniform or a core-shell double structure. In embodiments, materials included in the core may be different from materials included in the shell.

[0510] The shell of the quantum dot may be a protective layer that prevents chemical denaturation of the core to maintain semiconductor characteristics and/or may be a charging layer that imparts electrophoretic characteristics to the quantum dot. The shell may be a monolayer or a multilayer. An interface between a core and a shell may have a concentration gradient where a concentration of elements present in the shell decreases toward the core.

[0511] Examples of the shell of the quantum dot may include a metal oxide, a metalloid oxide, a nonmetal oxide, a semiconductor compound, or a combination thereof. Examples of the metal oxide, the metalloid oxide, or the nonmetal oxide may include a binary compound such as SiO.sub.2, Al.sub.2O.sub.3, TiO.sub.2, ZnO, MnO, Mn.sub.2O.sub.3, Mn.sub.3O.sub.4, CuO, FeO, Fe.sub.2O.sub.3, Fe.sub.3O.sub.4, CoO, Co.sub.3O.sub.4, or NiO; a ternary compound such as MgAl.sub.2O.sub.4, CoFe.sub.2O.sub.4, NiFe.sub.2O.sub.4, or CoMn.sub.2O.sub.4; or any combination thereof. Examples of the semiconductor compound may include a Group II-VI semiconductor compound; a Group III-V semiconductor compound; a Group III-VI semiconductor compound; a Group I-III-VI semiconductor compound; a Group IV-VI semiconductor compound; or any combination thereof. In embodiments, the semiconductor compound may be CdS, CdSe, CdTe, ZnS, ZnSe, ZnTe, ZnSeS, ZnTeS, GaAs, GaP, GaSb, HgS, HgSe, HgTe, InAs, InP, InGaP, InSb, AlAs, AlP, AlSb, or any combination thereof.

[0512] The quantum dot may have a full width of half maximum (FWHM) of a spectrum of an emission wavelength equal to or less than about 45 nm. For example, the quantum dot may have a FWHM of a spectrum of an emission wavelength equal to or less than about 40 nm. For example, the quantum dot may have a FWHM of a spectrum of an emission wavelength equal to or less than about 30 nm. When the FWHM of the quantum dot is within any of the above ranges, color purity or color reproducibility may be improved. Light emitted through the quantum dots may be emitted in all directions, and an optical viewing angle may be improved.

[0513] The quantum dot may be a spherical particle, a pyramidal particle, a multi-arm particle, a cubic nanoparticle, a nanotube, a nanowire, a nanofiber, or a nanoplate.

[0514] By adjusting the size of the quantum dot, the energy band gap may also be adjusted, thereby obtaining light of various wavelengths in the quantum dot emission layer. By using quantum dots of various sizes, a light-emitting device that may emit light of various wavelengths may be realized. In embodiments, the size of the quantum dot may be selected such that the quantum dot may emit red, green, and/or blue light. The size of the quantum dot may be selected such that the quantum dot may emit white light by combining various light colors.

[0515] [Electron Transport Region in Interlayer 130]

[0516] The electron transport region may have a structure consisting of a layer consisting of a single material, a structure consisting of a layer including different materials, or a multi-layered structure having layers including different materials.

[0517] The electron transport region may include a buffer layer, a hole blocking layer, an electron control layer, an electron transport layer, or an electron injection layer.

[0518] In embodiments, the electron transport region may have an electron transport layer/electron injection layer structure, a hole blocking layer/electron transport layer/electron injection layer structure, an electron control layer/electron transport layer/electron injection layer structure, or a buffer layer/electron transport layer/electron injection layer structure, wherein layers of each structure may be stacked on the emission layer in its respective stated order, but embodiments are not limited thereto.

[0519] The electron transport region (e.g., a buffer layer, a hole blocking layer, an electron control layer, or an electron transport layer in the electron transport region) may include a metal-free compound including at least one π electron-deficient nitrogen-containing C.sub.1-C.sub.60 cyclic group.

[0520] In embodiments, the electron transport region may include a compound represented by Formula 601:

[Ar.sub.601].sub.xe11-[(L.sub.601).sub.xe1-R.sub.601].sub.xe21  [Formula 601]

[0521] In Formula 601,

[0522] Ar.sub.601 and L.sub.601 may each independently be a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a,

[0523] xe11 may be 1, 2, or 3,

[0524] xe1 may be 0, 1, 2, 3, 4, or 5,

[0525] R.sub.6o1 may be a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a, a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a, —Si(Q.sub.601)(Q.sub.602)(Q.sub.603), —C(═O)(Q.sub.601), —S(═O).sub.2(Q.sub.601), or —P(═O)(Q.sub.601)(Q.sub.602),

[0526] Q.sub.601 to Q.sub.603 may each independently be understood by referring to the description of Q.sub.1 provided herein,

[0527] xe21 may be 1, 2, 3, 4, or 5, and

[0528] at least one of Ar.sub.601, L.sub.601, and R.sub.601 may each independently be a π electron-deficient nitrogen-containing C.sub.1-C.sub.60 cyclic group unsubstituted or substituted with at least one R.sub.10a, and R.sub.10a may be understood by referring to the description of R.sub.10a provided herein.

[0529] In embodiments, when xe11 in Formula 601 is 2 or greater, at least two Ar.sub.601(s) may be bound via a single bond.

[0530] In embodiments, in Formula 601, Ar.sub.601 may be a substituted or unsubstituted anthracene group.

[0531] In embodiments, the electron transport region may include a compound represented by Formula 601-1:

##STR00174##

[0532] In Formula 601-1,

[0533] X.sub.614 may be N or C(R.sub.614), X.sub.615 may be N or C(R.sub.615), X.sub.616 may be N or C(R.sub.616), and at least one of X.sub.614 to X.sub.616 may be N,

[0534] L.sub.611 to L.sub.613 may each independently be understood by referring to the description of L.sub.601 provided herein,

[0535] xe611 to xe613 may each independently be understood by referring to the description of xe1 provided herein,

[0536] R.sub.61n to R.sub.61i may each independently be understood by referring to the description of R.sub.6oi provided herein, and

[0537] R.sub.614 to R.sub.616 may each independently be hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, a C.sub.1-C.sub.20 alkyl group, a C.sub.1-C.sub.20 alkoxy group, a C.sub.3-C.sub.60 carbocyclic group unsubstituted or substituted with at least one R.sub.10a, or a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a, and R.sub.10a may be understood by referring to the description of R.sub.10a provided herein.

[0538] For example, in Formulae 601 and 601-1, xe1 and xe611 to xe613 may each independently be 0, 1, or 2.

[0539] The electron transport region may include one of Compounds ET1 to ET45, 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP), 4,7-diphenyl-1,10-phenanthroline (Bphen), Alq.sub.3, BAlq, TAZ, NTAZ, or any combination thereof:

##STR00175## ##STR00176## ##STR00177## ##STR00178## ##STR00179## ##STR00180## ##STR00181## ##STR00182## ##STR00183## ##STR00184## ##STR00185## ##STR00186## ##STR00187## ##STR00188## ##STR00189## ##STR00190##

[0540] A thickness of the electron transport region may be in a range of about 100 Angstroms (k) to about 5,000 k. For example, the thickness of the electron transport region may be in a range of about 100 Å to about 4,000 Å. When the electron transport region includes a buffer layer, a hole blocking layer, an electron control layer, an electron transport layer, or any combination thereof, a thickness of the buffer layer, the hole blocking layer, or the electron control layer may each independently be in a range of about 20 Å to about 1,000 Å, and a thickness of the electron transport layer may be in a range of about 100 Å to about 1,000 Å. For example, the thickness of the buffer layer, the hole blocking layer, or the electron control layer may each independently be in a range of about 30 Å to about 300 Å. For example, the thickness of the electron transport layer may be in a range of about 150 Å to about 500 Å. When the thicknesses of the buffer layer, the hole blocking layer, the electron control layer, and/or the electron transport layer are each within these ranges, excellent electron transport characteristics may be obtained without a substantial increase in driving voltage.

[0541] The electron transport region (for example, the electron transport layer in the electron transport region) may further include, in addition to the materials described above, a metal-containing material.

[0542] The metal-containing material may include an alkali metal complex, an alkaline earth metal complex, or any combination thereof. A metal ion of the alkali metal complex may be a lithium (Li) ion, a sodium (Na) ion, a potassium (K) ion, a rubidium (Rb) ion, or a cesium (Cs) ion. A metal ion of the alkaline earth metal complex may be a beryllium (Be) ion, a magnesium (Mg) ion, a calcium (Ca) ion, a strontium (Sr) ion, or a barium (Ba) ion. A ligand coordinated with the metal ion of the alkali metal complex and the alkaline earth metal complex may each independently be hydroxyquinoline, hydroxyisoquinoline, hydroxybenzoquinoline, hydroxyacridine, hydroxyphenanthridine, hydroxyphenyloxazole, hydroxyphenylthiazole, hydroxyphenyloxadiazole, hydroxyphenylthiadiazole, hydroxyphenylpyridine, hydroxyphenylbenzimidazole, hydroxyphenylbenzothiazole, bipyridine, phenanthroline, cyclopentadiene, or any combination thereof.

[0543] For example, the metal-containing material may include a Li complex. The Li complex may include, e.g., Compound ET-D1 (LiQ) or Compound ET-D2:

##STR00191##

[0544] The electron transport region may include an electron injection layer that facilitates injection of electrons from the second electrode 150. The electron injection layer may directly contact the second electrode 150.

[0545] The electron injection layer may have a structure consisting of a layer consisting of a single material, a structure consisting of a layer including different materials, or a multi-layered structure having layers including different materials.

[0546] The electron injection layer may include an alkali metal, an alkaline earth metal, a rare earth metal, an alkali metal-containing compound, an alkaline earth metal-containing compound, a rare earth metal-containing compound, an alkali metal complex, an alkaline earth metal complex, a rare earth metal complex, or any combination thereof.

[0547] The alkali metal may be Li, Na, K, Rb, Cs or any combination thereof. The alkaline earth metal may be Mg, Ca, Sr, Ba, or any combination thereof. The rare earth metal may be Sc, Y, Ce, Tb, Yb, Gd, or any combination thereof.

[0548] The alkali metal-containing compound, the alkaline earth metal-containing compound, and the rare earth metal-containing compound may respectively be oxides, halides (e.g., fluorides, chlorides, bromides, or iodides), tellurides, or any combination thereof of each of the alkali metal, the alkaline earth metal, and the rare earth metal.

[0549] The alkali metal-containing compound may be alkali metal oxides such as Li.sub.2O, Cs.sub.2O, or K.sub.2O, alkali metal halides such as LiF, NaF, CsF, KF, LiI, NaI, CsI, or KI, or any combination thereof. The alkaline earth-metal-containing compound may include alkaline earth-metal oxides, such as BaO, SrO, CaO, Ba.sub.xSr.sub.1-xO (wherein x is a real number satisfying 0<x<1), or Ba.sub.xCa.sub.1-xO (wherein x is a real number satisfying 0<x<1). The rare earth metal-containing compound may include YbF.sub.3, ScF.sub.3, Sc.sub.2O.sub.3, Y.sub.2O.sub.3, Ce.sub.2O.sub.3, GdF.sub.3, TbF.sub.3, YbI.sub.3, ScI.sub.3, TbI.sub.3, or any combination thereof. In embodiments, the rare earth metal-containing compound may include a lanthanide metal telluride. Examples of the lanthanide metal telluride may include LaTe, CeTe, PrTe, NdTe, PmTe, SmTe, EuTe, GdTe, TbTe, DyTe, HoTe, ErTe, TmTe, YbTe, LuTe, La.sub.2Te.sub.3, Ce.sub.2Te.sub.3, Pr.sub.2Te.sub.3, Nd.sub.2Te.sub.3, Pm.sub.2Te.sub.3, Sm.sub.2Te.sub.3, Eu.sub.2Te.sub.3, Gd.sub.2Te.sub.3, Tb.sub.2Te.sub.3, Dy.sub.2Te.sub.3, Ho.sub.2Te.sub.3, Er.sub.2Te.sub.3, Tm.sub.2Te.sub.3, Yb.sub.2Te.sub.3, Lu.sub.2Te.sub.3, and the like.

[0550] The alkali metal complex, the alkaline earth metal complex, and the rare earth metal complex may include one of ions of the alkali metal, ions of the alkaline earth metal, and ions of the rare earth metal described above, and a ligand bonded to the metal ion, e.g., hydroxyquinoline, hydroxyisoquinoline, hydroxybenzoquinoline, hydroxyacridine, hydroxyphenanthridine, hydroxyphenyloxazole, hydroxyphenylthiazole, hydroxyphenyloxadiazole, hydroxyphenylthiadiazole, hydroxyphenylpyridine, hydroxyphenylbenzimidazole, hydroxyphenylbenzothiazole, bipyridine, phenanthroline, cyclopentadiene, or any combination thereof.

[0551] The electron injection layer may consist of an alkali metal, an alkaline earth metal, a rare earth metal, an alkali metal-containing compound, an alkaline earth metal-containing compound, a rare earth metal-containing compound, an alkali metal complex, an alkaline earth metal complex, a rare earth metal complex, or any combination thereof, as described above. In embodiments, the electron injection layer may further include an organic material (e.g., a compound represented by Formula 601).

[0552] In embodiments, the electron injection layer may consist of an alkali metal-containing compound (e.g., alkali metal halide); or an alkali metal-containing compound (e.g., alkali metal halide), and an alkali metal, an alkaline earth metal, a rare earth metal, or any combination thereof. In embodiments, the electron injection layer may be a KI:Yb co-deposition layer, a RbI:Yb co-deposition layer, and the like.

[0553] When the electron injection layer further includes an organic material, the alkali metal, the alkaline earth metal, the rare earth metal, the alkali metal-containing compound, the alkaline earth metal-containing compound, the rare earth metal-containing compound, the alkali metal complex, the alkaline earth metal complex, the rare earth metal complex, or any combination thereof may be homogeneously or non-homogeneously dispersed in a matrix including the organic material.

[0554] A thickness of the electron injection layer may be in a range of about 1 Å to about 100 Å. For example, the thickness of the electron injection layer may be in a range of about 3 Å to about 90 Å. When the thickness of the electron injection layer is within any of these ranges, excellent electron injection characteristics may be obtained without a substantial increase in driving voltage.

[0555] [Second Electrode 150]

[0556] The second electrode 150 may be on the interlayer 130. In an embodiment, the second electrode 150 may be a cathode that is an electron injection electrode, and a material for forming the second electrode 150 may be a material having a low work function, such as a metal, an alloy, an electrically conductive compound, or any combination thereof.

[0557] The second electrode 150 may include lithium (Li), silver (Ag), magnesium (Mg), aluminum (Al), aluminum-lithium (Al—Li), calcium (Ca), magnesium-indium (Mg—In), magnesium-silver (Mg—Ag), ytterbium (Yb), silver-ytterbium (Ag—Yb), ITO, IZO, or any combination thereof. The second electrode 150 may be a transmissive electrode, a transflective electrode, or a reflective electrode.

[0558] The second electrode 150 may have a single-layered structure, or a multi-layered structure including two or more layers.

[0559] [Capping Layer]

[0560] A first capping layer may be located outside the first electrode 110, and/or a second capping layer may be located outside the second electrode 150. In embodiments, the light-emitting device 10 may have a structure in which the first capping layer, the first electrode 110, the interlayer 130, and the second electrode 150 are stacked in this stated order, a structure in which the first electrode 110, the interlayer 130, the second electrode 150, and the second capping layer are stacked in this stated order, or a structure in which the first capping layer, the first electrode 110, the interlayer 130, the second electrode 150, and the second capping layer are stacked in this stated order.

[0561] In the light-emitting device 10, light emitted from the emission layer in the interlayer 130 may pass through the first electrode 110 (which may be a transflective electrode or a transmissive electrode) and through the first capping layer to the outside. In the light-emitting device 10, light emitted from the emission layer in the interlayer 130 may pass through the second electrode 150 (which may be a transflective electrode or a transmissive electrode) and through the second capping layer to the outside.

[0562] The first capping layer and the second capping layer may each improve the external luminescence efficiency based on the principle of constructive interference. Accordingly, the optical extraction efficiency of the light-emitting device 10 may be increased, thus improving the luminescence efficiency of the light-emitting device 10.

[0563] The first capping layer and the second capping layer may each include a material having a refractive index equal to or greater than about 1.6 (at a wavelength of about 589 nm).

[0564] The first capping layer and the second capping layer may each independently be an organic capping layer including an organic material, an inorganic capping layer including an inorganic material, or an organic-inorganic composite capping layer including an organic material and an inorganic material.

[0565] At least one of the first capping layer and the second capping layer may each independently include carbocyclic compounds, heterocyclic compounds, amine group-containing compounds, porphine derivatives, phthalocyanine derivatives, naphthalocyanine derivatives, alkali metal complexes, alkaline earth metal complexes, or any combination thereof. The carbocyclic compound, the heterocyclic compound, and the amine group-containing compound may each independently be optionally substituted with a substituent including O, N, S, Se, Si, F, Cl, Br, I, or any combination thereof. In embodiments, at least one of the first capping layer and the second capping layer may each independently include an amine group-containing compound.

[0566] In embodiments, at least one of the first capping layer and the second capping layer may each independently include the compound represented by Formula 201, the compound represented by Formula 202, or any combination thereof.

[0567] In embodiments, at least one of the first capping layer and the second capping layer may each independently include one of Compounds HT28 to HT33, one of Compounds CP1 to CP6, β-NPB, or any combination thereof.

##STR00192##

[0568] [Film]

[0569] The organometallic compound represented by Formula 1 may be included in various films. According to embodiments, a film including an organometallic compound represented by Formula 1 may be provided. The film may be, for example, an optical member (or a light-controlling member) (e.g., a color filter, a color-conversion member, a capping layer, a light extraction efficiency improvement layer, a selective light-absorbing layer, a polarization layer, a quantum dot-containing layer, or the like), a light-blocking member (e.g., a light reflection layer or a light-absorbing layer), or a protection member (e.g., an insulating layer or a dielectric material layer).

[0570] [Electronic Apparatus]

[0571] The light-emitting device may be included in various electronic apparatuses. In embodiments, an electronic apparatus including the light-emitting device may be an emission apparatus or an authentication apparatus.

[0572] The electronic apparatus (e.g., an emission apparatus) may further include, in addition to the light-emitting device, a color filter, a color-conversion layer, or a color filter and a color-conversion layer. The color filter and/or the color-conversion layer may be disposed on at least one traveling direction of light emitted from the light-emitting device. For example, light emitted from the light-emitting device may be blue light or white light. The light-emitting device may be understood by referring to the descriptions provided herein. In embodiments, the color-conversion layer may include quantum dots. The quantum dot may be, for example, the quantum dot described herein.

[0573] The electronic apparatus may include a first substrate. The first substrate may include subpixels, the color filter may include color filter areas respectively corresponding to the subpixels, and the color-conversion layer may include color-conversion areas respectively corresponding to the subpixels.

[0574] A pixel-defining film may be located between the subpixels to define each subpixel.

[0575] The color filter may further include color filter areas and light-blocking patterns between the color filter areas, and the color-conversion layer may further include color-conversion areas and light-blocking patterns between the color-conversion areas.

[0576] The color filter areas (or the color-conversion areas) may include a first area emitting first color light, a second area emitting second color light, and/or a third area emitting third color light, and the first color light, the second color light, and/or the third color light may have different maximum emission wavelengths from one another. In embodiments, the first color light may be red light, the second color light may be green light, and the third color light may be blue light. In embodiments, the color filter areas (or the color-conversion areas) may each include quantum dots. In embodiments, the first area may include red quantum dots, the second area may include green quantum dots, and the third area may not include a quantum dot. The quantum dot may be understood by referring to the description of the quantum dot provided herein. The first area, the second area, and/or the third area may each further include a scatterer.

[0577] In embodiments, the light-emitting device may emit first light, the first area may absorb the first light to emit 1-1 color light, the second area may absorb the first light to emit 2-1 color light, and the third area may absorb the first light to emit 3-1 color light. In this embodiment, the 1-1 color light, the 2-1 color light, and the 3-1 color light may each have a different maximum emission wavelength from one another. In embodiments, the first light may be blue light, the 1-1 color light may be red light, the 2-1 color light may be green light, and the 3-1 color light may be blue light.

[0578] The electronic apparatus may further include a thin-film transistor, in addition to the light-emitting device. The thin-film transistor may include a source electrode, a drain electrode, and an active layer, wherein one of the source electrode and the drain electrode may be electrically connected to one of the first electrode and the second electrode of the light-emitting device.

[0579] The thin-film transistor may further include a gate electrode, a gate insulating film, or the like.

[0580] The active layer may include a crystalline silicon, an amorphous silicon, an organic semiconductor, and an oxide semiconductor.

[0581] The electronic apparatus may further include an encapsulation unit for sealing the light-emitting device. The encapsulation unit may be located between the color filter and/or the color-conversion layer and the light-emitting device. The encapsulation unit may allow light to pass to the outside from the light-emitting device and may prevent air and/or moisture from permeating into the light-emitting device at the same time. The encapsulation unit may be a sealing substrate including transparent glass or a plastic substrate. The encapsulation unit may be a thin-film encapsulating layer including at least one of an organic layer and an inorganic layer. When the encapsulation unit is a thin-film encapsulating layer, the electronic apparatus may be flexible.

[0582] In addition to the color filter and/or the color-conversion layer, various functional layers may be disposed on the encapsulation unit depending on the use of an electronic apparatus. Examples of the functional layer may include a touch screen layer, a polarization layer, an authentication apparatus, or the like. The touch screen layer may be a resistive touch screen layer, a capacitive touch screen layer, or an infrared beam touch screen layer. The authentication apparatus may be, for example, a biometric authentication apparatus that identifies an individual according to biometric information (e.g., a fingertip, a pupil, or the like).

[0583] The authentication apparatus may further include a biometric information collecting unit, in addition to the light-emitting device described above.

[0584] The electronic apparatus may be applicable to various displays, such as an optical source, lighting, a personal computer (e.g., a mobile personal computer), a cellphone, a digital camera, an electronic note, an electronic dictionary, an electronic game console, a medical device (e.g., an electronic thermometer, a blood pressure meter, a glucometer, a pulse measuring device, a pulse wave measuring device, an electrocardiograph recorder, an ultrasonic diagnosis device, or an endoscope display device), a fish finder, various measurement devices, gauges (e.g., gauges of an automobile, an airplane, or a ship), and a projector.

[0585] [Descriptions of FIGS. 2 and 3]

[0586] FIG. 2 is a schematic cross-sectional view of an electronic apparatus according to an embodiment.

[0587] An electronic apparatus in FIG. 2 may include a substrate 100, a thin-film transistor, a light-emitting device, and an encapsulation unit 300 sealing the light-emitting device.

[0588] The substrate 100 may be a flexible substrate, a glass substrate, or a metal substrate. A buffer layer 210 may be on the substrate 100. The buffer layer 210 may prevent penetration of impurities through the substrate 100 and provide a flat surface on the substrate 100.

[0589] A thin-film transistor may be on the buffer layer 210. The thin-film transistor may include an active layer 220, a gate electrode 240, a source electrode 260, and a drain electrode 270.

[0590] The active layer 220 may include an inorganic semiconductor such as silicon or polysilicon, an organic semiconductor, or an oxide semiconductor and include a source area, a drain area, and a channel area.

[0591] A gate insulating film 230 for insulating the active layer 220 and the gate electrode 240 may be on the active layer 220, and the gate electrode 240 may be on the gate insulating film 230.

[0592] An interlayer insulating film 250 may be on the gate electrode 240. The interlayer insulating film 250 may be between the gate electrode 240 and the source electrode 260 and between the gate electrode 240 and the drain electrode 270 to provide insulation therebetween.

[0593] The source electrode 260 and the drain electrode 270 may be on the interlayer insulating film 250. The interlayer insulating film 250 and the gate insulating film 230 may be formed to expose the source area and the drain area of the active layer 220, and the source electrode 260 and the drain electrode 270 may be adjacent to the exposed source area and the exposed drain area of the active layer 220.

[0594] Such a thin-film transistor may be electrically connected to a light-emitting device to drive the light-emitting device and may be protected by a passivation layer 280. The passivation layer 280 may include an inorganic insulating film, an organic insulating film, or a combination thereof. A light-emitting device may be on the passivation layer 280. The light-emitting device may include a first electrode 110, an interlayer 130, and a second electrode 150.

[0595] The first electrode 110 may be on the passivation layer 280. The passivation layer 280 may not fully cover the drain electrode 270 and expose a specific area of the drain electrode 270, and the first electrode 110 may be disposed to electrically connect to the exposed area of the drain electrode 270.

[0596] A pixel-defining film 290 may be on the first electrode 110. The pixel-defining film 290 may expose a specific area of the first electrode 110, and the interlayer 130 may be formed in the exposed area. The pixel-defining film 290 may be a polyimide or polyacryl organic film. Although it is not shown in FIG. 2, some higher layers of the interlayer 130 may extend to the upper portion of the pixel-defining film 290 and may be disposed in the form of a common layer.

[0597] The second electrode 150 may be on the interlayer 130, and a capping layer 170 may be additionally formed on the second electrode 150. The capping layer 170 may be formed to cover the second electrode 150.

[0598] The encapsulation unit 300 may be on the capping layer 170. The encapsulation unit 300 may be on the light-emitting device to protect a light-emitting device from moisture and/or oxygen. The encapsulation unit 300 may include an inorganic film including silicon nitride (SiN.sub.x), silicon oxide (SiO.sub.x), indium tin oxide, indium zinc oxide, or any combination thereof, an organic film including PET, polyethylene naphthalate, polycarbonate, polyimide, polyethylene sulfonate, polyoxy methylene, polyaryllate, hexamethyl disiloxane, an acrylic based resin (e.g., polymethyl methacrylate, polyacrylic acid, and the like), an epoxy based resin (e.g., aliphatic glycidyl ether (AGE) and the like), or any combination thereof; or a combination of the inorganic film and the organic film.

[0599] FIG. 3 is a schematic cross-sectional view of an electronic apparatus according to an embodiment.

[0600] The electronic apparatus shown in FIG. 3 may be substantially identical to the electronic apparatus shown in FIG. 2, except that a light-blocking pattern 500 and a functional area 400 are additionally located on the encapsulation unit 300. The functional area 400 may be a color filter area, a color-conversion area, or a combination of a color filter area and a color-conversion area. In embodiments, the light-emitting device included in the electronic apparatus shown in FIG. 3 may be a tandem light-emitting device.

[0601] [Manufacturing Method]

[0602] The layers constituting the hole transport region, the emission layer, and the layers constituting the electron transport region may be formed in a specific region by using one or more suitable methods such as vacuum deposition, spin coating, casting, Langmuir-Blodgett (LB) deposition, ink-jet printing, laser printing, and laser-induced thermal imaging.

[0603] When layers constituting the hole transport region, an emission layer, and layers constituting the electron transport region are each independently formed by vacuum-deposition, the vacuum-deposition may be performed at a deposition temperature in a range of about 100° C. to about 500° C., at a vacuum degree in a range of about 10.sup.−8 torr to about 10.sup.−3 torr, and at a deposition rate in a range of about 0.01 Angstroms per second (A/sec) to about 100 Å/sec, depending on the material to be included in each layer and the structure of each layer to be formed.

Definitions of Terms

[0604] The term “C.sub.3-C.sub.60 carbocyclic group” as used herein may be a cyclic group consisting only of carbon atoms as ring-forming atoms and having 3 to 60 carbon atoms as ring-forming atoms. The term “C.sub.1-C.sub.60 heterocyclic group” as used herein may be a cyclic group having 1 to 60 carbon atoms in addition to at least one heteroatom as ring-forming atoms other than carbon atoms. The C.sub.3-C.sub.60 carbocyclic group and the C.sub.1-C.sub.60 heterocyclic group may each be a monocyclic group consisting of one ring or a polycyclic group in which at least two rings are condensed. For example, the number of ring-forming atoms in a C.sub.1-C.sub.60 heterocyclic group may be in a range of 3 to 61.

[0605] The term “cyclic group” as used herein may include the C.sub.3-C.sub.60 carbocyclic group and the C.sub.1-C.sub.60 heterocyclic group.

[0606] The term “n electron-rich C.sub.3-C.sub.60 cyclic group” as used herein may be a cyclic group having 3 to 60 carbon atoms and not including *—N=*′ as a ring-forming moiety. The term “R electron-deficient nitrogen-containing C.sub.1-C.sub.60 cyclic group” as used herein may be a heterocyclic group having 1 to 60 carbon atoms and may include *—N=*′ as a ring-forming moiety.

[0607] In embodiments,

[0608] the C.sub.3-C.sub.60 carbocyclic group may be a T1 group or a group in which at least two T1 groups are condensed (for example, a cyclopentadiene group, an adamantane group, a norbornane group, a benzene group, a pentalene group, a naphthalene group, an azulene group, an indacene group, an acenaphthylene group, a phenalene group, a phenanthrene group, an anthracene group, a fluoranthene group, a triphenylene group, a pyrene group, a chrysene group, a perylene group, a pentaphene group, a heptalene group, a naphthacene group, a picene group, a hexacene group, a pentacene group, a rubicene group, a coronene group, an ovalene group, an indene group, a fluorene group, a spiro-bifluorene group, a benzofluorene group, an indenophenanthrene group, or an indenoanthracene group),

[0609] the C.sub.1-C.sub.60 heterocyclic group may be a T2 group, a group in which at least two T2 groups are condensed, or a group in which at least one T2 group is condensed with at least one T1 group (for example, a pyrrole group, a thiophene group, a furan group, an indole group, a benzoindole group, a naphthoindole group, an isoindole group, a benzoisoindole group, a naphthoisoindole group, a benzosilole group, a benzothiophene group, a benzofuran group, a carbazole group, a dibenzosilole group, a dibenzothiophene group, a dibenzofuran group, an indenocarbazole group, an indolocarbazole group, a benzofurocarbazole group, a benzothienocarbazole group, a benzosilolocarbazole group, a benzoindolocarbazole group, a benzocarbazole group, a benzonaphthofuran group, a benzonapthothiophene group, a benzonaphthosilole group, a benzofurodibenzofuran group, a benzofurodibenzothiophene group, a benzothienodibenzothiophene group, a pyrazole group, an imidazole group, a triazole group, an oxazole group, an isoxazole group, an oxadiazole group, a thiazole group, an isothiazole group, a thiadiazole group, a benzopyrazole group, a benzimidazole group, a benzoxazole group, a benzoisoxazole group, a benzothiazole group, a benzoisothiazole group, a pyridine group, a pyrimidine group, a pyrazine group, a pyridazine group, a triazine group, a quinoline group, an isoquinoline group, a benzoquinoline group, a benzoisoquinoline group, a quinoxaline group, a benzoquinoxaline group, a quinazoline group, a benzoquinazoline group, a phenanthroline group, a cinnoline group, a phthalazine group, a naphthyridine group, an imidazopyridine group, an imidazopyrimidine group, an imidazotriazine group, an imidazopyrazine group, an imidazopyridazine group, an azacarbazole group, an azafluorene group, an azadibenzosilole group, an azadibenzothiophene group, an azadibenzofuran group, and the like),

[0610] the π electron-rich C.sub.3-C.sub.60 cyclic group may be a T1 group, a condensed group in which at least two T1 groups are condensed, a T3 group, a condensed group in which at least two T3 groups are condensed, or a condensed group in which at least one T3 group is condensed with at least one T1 group (for example, a C.sub.3-C.sub.60 carbocyclic group, a 1H-pyrrole group, a silole group, a borole group, a 2H-pyrrole group, a 3H-pyrrole group, a thiophene group, a furan group, an indole group, a benzoindole group, a naphthoindole group, an isoindole group, a benzoisoindole group, a naphthoisoindole group, a benzosilole group, a benzothiophene group, a benzofuran group, a carbazole group, a dibenzosilole group, a dibenzothiophene group, a dibenzofuran group, an indenocarbazole group, an indolocarbazole group, a benzofurocarbazole group, a benzothienocarbazole group, a benzosilolocarbazole group, a benzoindolocarbazole group, a benzocarbazole group, a benzonaphthofuran group, a benzonapthothiophene group, a benzonaphthosilole group, a benzofurodibenzofuran group, a benzofurodibenzothiophene group, a benzothienodibenzothiophene group, and the like), and

[0611] the π electron-deficient nitrogen-containing C.sub.1-C.sub.60 cyclic group may be a T.sub.4 group, a group in which at least two T4 groups are condensed, a group in which at least one T4 group is condensed with at least one T1 group, a group in which at least one T4 group is condensed with at least one T3 group, or a group in which at least one T4 group, at least one T1 group, and at least one T3 group are condensed (for example, a pyrazole group, an imidazole group, a triazole group, an oxazole group, an isoxazole group, an oxadiazole group, a thiazole group, an isothiazole group, a thiadiazole group, a benzopyrazole group, a benzimidazole group, a benzoxazole group, a benzoisoxazole group, a benzothiazole group, a benzoisothiazole group, a pyridine group, a pyrimidine group, a pyrazine group, a pyridazine group, a triazine group, a quinoline group, an isoquinoline group, a benzoquinoline group, a benzoisoquinoline group, a quinoxaline group, a benzoquinoxaline group, a quinazoline group, a benzoquinazoline group, a phenanthroline group, a cinnoline group, a phthalazine group, a naphthyridine group, an imidazopyridine group, an imidazopyrimidine group, an imidazotriazine group, an imidazopyrazine group, an imidazopyridazine group, an azacarbazole group, an azafluorene group, an azadibenzosilole group, an azadibenzothiophene group, an azadibenzofuran group, and the like),

[0612] wherein the T1 group may be a cyclopropane group, a cyclobutane group, a cyclopentane group, a cyclohexane group, a cycloheptane group, a cyclooctane group, a cyclobutene group, a cyclopentene group, a cyclopentadiene group, a cyclohexene group, a cyclohexadiene group, a cycloheptene group, an adamantane group, a norbornane (or bicyclo[2.2.1]heptane) group, a norbornene group, a bicyclo[1.1.1]pentane group, a bicyclo[2.1.1]hexane group, a bicyclo[2.2.2]octane group, or a benzene group,

[0613] the T2 group may be a furan group, a thiophene group, a 1H-pyrrole group, a silole group, a borole group, a 2H-pyrrole group, a 3H-pyrrole group, an imidazole group, a pyrazole group, a triazole group, a tetrazole group, an oxazole group, an isoxazole group, an oxadiazole group, a thiazole group, an isothiazole group, a thiadiazole group, an azasilole group, an azaborole group, a pyridine group, a pyrimidine group, a pyrazine group, a pyridazine group, a triazine group, a tetrazine group, a pyrrolidine group, an imidazolidine group, a dihydropyrrole group, a piperidine group, a tetrahydropyridine group, a dihydropyridine group, a hexahydropyrimidine group, a tetrahydropyrimidine group, a dihydropyrimidine group, a piperazine group, a tetrahydropyrazine group, a dihydropyrazine group, a tetrahydropyridazine group, or a dihydropyridazine group,

[0614] the T3 group may be a furan group, a thiophene group, a 1H-pyrrole group, a silole group, or a borole group, and

[0615] the T4 group may be a 2H-pyrrole group, a 3H-pyrrole group, an imidazole group, a pyrazole group, a triazole group, a tetrazole group, an oxazole group, an isoxazole group, an oxadiazole group, a thiazole group, an isothiazole group, a thiadiazole group, an azasilole group, an azaborole group, a pyridine group, a pyrimidine group, a pyrazine group, a pyridazine group, a triazine group, or a tetrazine group.

[0616] The terms “cyclic group”, “C.sub.3-C.sub.60 carbocyclic group”, “C.sub.1-C.sub.60 heterocyclic group”, “π electron-rich C.sub.3-C.sub.60 cyclic group”, or “n electron-deficient nitrogen-containing C.sub.1-C.sub.60 cyclic group” as used herein may be a group condensed with any suitable cyclic group, a monovalent group, or a polyvalent group (e.g., a divalent group, a trivalent group, a tetravalent group, or the like), depending on the structure of a formula to which the term is applied. For example, a “benzene group” may be a benzene ring, a phenyl group, a phenylene group, or the like, and this may be understood by one of ordinary skill in the art, depending on the structure of the formula including the “benzene group”.

[0617] Examples of the monovalent C.sub.3-C.sub.60 carbocyclic group and the monovalent C.sub.1-C.sub.60 heterocyclic group may include a C.sub.3-C.sub.10 cycloalkyl group, a C.sub.1-C.sub.10 heterocycloalkyl group, a C.sub.3-C.sub.10 cycloalkenyl group, a C.sub.1-C.sub.10 heterocycloalkenyl group, a C.sub.6-C.sub.60 aryl group, a C.sub.1-C.sub.60 heteroaryl group, a monovalent non-aromatic condensed polycyclic group, and a monovalent non-aromatic condensed heteropolycyclic group. Examples of the divalent C.sub.3-C.sub.60 carbocyclic group and the divalent C.sub.1-C.sub.60 heterocyclic group may include a C.sub.3-C.sub.10 cycloalkylene group, a C.sub.1-C.sub.10 heterocycloalkylene group, a C.sub.3-C.sub.10 cycloalkenylene group, a C.sub.1-C.sub.10 heterocycloalkenylene group, a C.sub.6-C.sub.60 arylene group, a C.sub.1-C.sub.60 heteroarylene group, a divalent non-aromatic condensed polycyclic group, and a divalent non-aromatic condensed heteropolycyclic group.

[0618] The term “C.sub.1-C.sub.60 alkyl group” as used herein may be a linear or branched aliphatic hydrocarbon monovalent group having 1 to 60 carbon atoms. Examples of the C.sub.1-C.sub.60 alkyl group may include a methyl group, an ethyl group, an n-propyl group, an iso-propyl group, an n-butyl group, a sec-butyl group, an isobutyl group, a tert-butyl group, an n-pentyl group, a tert-pentyl group, a neopentyl group, an isopentyl group, a sec-pentyl group, a 3-pentyl group, a sec-isopentyl group, an n-hexyl group, an iso-hexyl group, a sec-hexyl group, a tert-hexyl group, an n-heptyl group, an iso-heptyl group, a sec-heptyl group, a tert-heptyl group, an n-octyl group, an iso-octyl group, a sec-octyl group, a tert-octyl group, an n-nonyl group, an iso-nonyl group, a sec-nonyl group, a tert-nonyl group, an n-decyl group, an iso-decyl group, a sec-decyl group, and a tert-decyl group. The term “C.sub.1-C.sub.60 alkylene group” as used herein may be a divalent group having a same structure as the C.sub.1-C.sub.60 alkyl group.

[0619] The term “C.sub.2-C.sub.60 alkenyl group” as used herein may be a monovalent hydrocarbon group having at least one carbon-carbon double bond in the middle or at the terminus of the C.sub.2-C.sub.60 alkyl group. Examples thereof may include an ethenyl group, a propenyl group, and a butenyl group. The term “C.sub.2-C.sub.60 alkenylene group” as used herein may be a divalent group having a same structure as the C.sub.2-C.sub.60 alkenyl group.

[0620] The term “C.sub.2-C.sub.60 alkynyl group” as used herein may be a monovalent hydrocarbon group having at least one carbon-carbon triple bond in the middle or at the terminus of the C.sub.2-C.sub.60 alkyl group. Examples thereof may include an ethynyl group and a propynyl group. The term “C.sub.2-C.sub.60 alkynylene group” as used herein may be a divalent group having a same structure as the C.sub.2-C.sub.60 alkynyl group.

[0621] The term “C.sub.1-C.sub.60 alkoxy group” as used herein may be a monovalent group represented by —O(A.sub.101) (wherein A.sub.101 is a C.sub.1-C.sub.60 alkyl group). Examples thereof may include a methoxy group, an ethoxy group, and an isopropyloxy group.

[0622] The term “C.sub.3-C.sub.10 cycloalkyl group” as used herein may be a monovalent saturated hydrocarbon monocyclic group including 3 to 10 carbon atoms. Examples of the C.sub.3-C.sub.10 cycloalkyl group as used herein may include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, an adamantanyl group, a norbornanyl (bicyclo[2.2.1]heptyl) group, a bicyclo[1.1.1]pentyl group, a bicyclo[2.1.1]hexyl group, or a bicyclo[2.2.2]octyl group. The term “C.sub.3-C.sub.10 cycloalkylene group” as used herein may be a divalent group having a same structure as the C.sub.3-C.sub.10 cycloalkyl group.

[0623] The term “C.sub.1-C.sub.10 heterocycloalkyl group” as used herein may be a monovalent cyclic group including at least one heteroatom other than carbon atoms as a ring-forming atom and having 1 to 10 carbon atoms. Examples thereof may include a 1,2,3,4-oxatriazolidinyl group, a tetrahydrofuranyl group, and a tetrahydrothiophenyl group. The term “C.sub.1-C.sub.10 heterocycloalkylene group” as used herein may be a divalent group having a same structure as the C.sub.1-C.sub.10 heterocycloalkyl group.

[0624] The term “C.sub.3-C.sub.10 cycloalkenyl group” as used herein may be a monovalent cyclic group that has 3 to 10 carbon atoms and at least one carbon-carbon double bond in its ring, and is not aromatic. Examples thereof may include a cyclopentenyl group, a cyclohexenyl group, and a cycloheptenyl group. The term “C.sub.3-C.sub.10 cycloalkenylene group” as used herein may be a divalent group having a same structure as the C.sub.3-C.sub.10 cycloalkenyl group.

[0625] The term “C.sub.1-C.sub.10 heterocycloalkenyl group” as used herein may be a monovalent cyclic group including at least one heteroatom other than carbon atoms as a ring-forming atom, 1 to 10 carbon atoms, and at least one double bond in its ring. Examples of the C.sub.1-C.sub.10 heterocycloalkenyl group may include a 4,5-dihydro-1,2,3,4-oxatriazolyl group, a 2,3-dihydrofuranyl group, and a 2,3-dihydrothiophenyl group. The term “C.sub.1-C.sub.10 heterocycloalkenylene group” as used herein may be a divalent group having a same structure as the C.sub.1-C.sub.10 heterocycloalkenyl group.

[0626] The term “C.sub.6-C.sub.60 aryl group” as used herein may be a monovalent group having a carbocyclic aromatic system having 6 to 60 carbon atoms. The term “C.sub.6-C.sub.60 arylene group” as used herein may be a divalent group having a carbocyclic aromatic system having 6 to 60 carbon atoms. Examples of the C.sub.6-C.sub.60 aryl group may include a phenyl group, a pentalenyl group, a naphthyl group, an azulenyl group, an indacenyl group, an acenaphthyl group, a phenalenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a perylenyl group, a pentaphenyl group, a heptalenyl group, a naphthacenyl group, a picenyl group, a hexacenyl group, a pentacenyl group, a rubicenyl group, a coronenyl group, and an ovalenyl group. When the C.sub.6-C.sub.60 aryl group and the C.sub.6-C.sub.60 arylene group each independently include two or more rings, the respective rings may be fused.

[0627] The term “C.sub.1-C.sub.60 heteroaryl group” as used herein may be a monovalent group having a heterocyclic aromatic system further including at least one heteroatom other than carbon atoms as a ring-forming atom and 1 to 60 carbon atoms. The term “C.sub.1-C.sub.60 heteroarylene group” as used herein may be a divalent group having a heterocyclic aromatic system further including at least one heteroatom other than carbon atoms as a ring-forming atom and 1 to 60 carbon atoms. Examples of the C.sub.1-C.sub.60 heteroaryl group may include a pyridinyl group, a pyrimidinyl group, a pyrazinyl group, a pyridazinyl group, a triazinyl group, a quinolinyl group, a benzoquinolinyl group, an isoquinolinyl group, a benzoisoquinolinyl group, a quinoxalinyl group, a benzoquinoxalinyl group, a quinazolinyl group, a benzoquinazolinyl group, a cinnolinyl group, a phenanthrolinyl group, a phthalazinyl group, and a naphthyridinyl group. When the C.sub.1-C.sub.60 heteroaryl group and the C.sub.1-C.sub.60 heteroarylene group each independently include two or more rings, the respective rings may be fused.

[0628] The term “monovalent non-aromatic condensed polycyclic group” as used herein may be a monovalent group that has two or more condensed rings and only carbon atoms (e.g., 8 to 60 carbon atoms) as ring forming atoms, wherein the molecular structure when considered as a whole is non-aromatic. Examples of the monovalent non-aromatic condensed polycyclic group may include an indenyl group, a fluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, an indenophenanthrenyl group, and an indenoanthracenyl group. The term “divalent non-aromatic condensed polycyclic group” as used herein may be a divalent group having substantially a same structure as the monovalent non-aromatic condensed polycyclic group.

[0629] The term “monovalent non-aromatic condensed heteropolycyclic group” as used herein may be a monovalent group that has two or more condensed rings and at least one heteroatom other than carbon atoms (e.g., 1 to 60 carbon atoms), as a ring-forming atom, wherein the molecular structure when considered as a whole is non-aromatic. Examples of the monovalent non-aromatic condensed heteropolycyclic group may include a pyrrolyl group, a thiophenyl group, a furanyl group, an indolyl group, a benzoindolyl group, a naphthoindolyl group, an isoindolyl group, a benzoisoindolyl group, a naphthoisoindolyl group, a benzosilolyl group, a benzothiophenyl group, a benzofuranyl group, a carbazolyl group, a dibenzosilolyl group, a dibenzothiophenyl group, a dibenzofuranyl group, an azacarbazolyl group, an azafluorenyl group, an azadibenzosilolyl group, an azadibenzothiophenyl group, an azadibenzofuranyl group, a pyrazolyl group, an imidazolyl group, a triazolyl group, a tetrazolyl group, an oxazolyl group, an isoxazolyl group, a thiazolyl group, an isothiazolyl group, an oxadiazolyl group, a thiadiazolyl group, a benzopyrazolyl group, a benzimidazolyl group, a benzoxazolyl group, a benzothiazolyl group, a benzooxadiazolyl group, a benzothiadiazolyl group, an imidazopyridinyl group, an imidazopyrimidinyl group, an imidazotriazinyl group, an imidazopyrazinyl group, an imidazopyridazinyl group, an indenocarbazolyl group, an indolocarbazolyl group, a benzofurocarbazolyl group, a benzothienocarbazolyl group, a benzosilolocarbazolyl group, a benzoindolocarbazolyl group, a benzocarbazolyl group, a benzonaphthofuranyl group, a benzonaphthothiophenyl group, a benzonaphthosilolyl group, a benzofurodibenzofuranyl group, a benzofurodibenzothiophenyl group, and a benzothienodibenzothiophenyl group. The term “divalent non-aromatic condensed heteropolycyclic group” as used herein may be a divalent group having substantially a same structure as the monovalent non-aromatic condensed heteropolycyclic group.

[0630] The term “C.sub.6-C.sub.60 aryloxy group” as used herein indicates —OA.sub.102 (wherein A.sub.102 is a C.sub.6-C.sub.60 aryl group), and a C.sub.6-C.sub.60 arylthio group as used herein indicates —SA.sub.103 (wherein A.sub.103 is a C.sub.6-C.sub.60 aryl group).

[0631] The term “C.sub.7-C.sub.60 aryl alkyl group” used herein refers to -A.sub.104A.sub.105 (where A.sub.104 may be a C.sub.1-C.sub.54 alkylene group, and A.sub.105 may be a C.sub.6-C.sub.59 aryl group), and the term “C.sub.2-C.sub.60 heteroaryl alkyl group” used herein refers to -A.sub.106A.sub.107 (where A.sub.106 may be a C.sub.1-C.sub.59 alkylene group, and A.sub.107 may be a C.sub.1-C.sub.59 heteroaryl group).

[0632] The term “R.sub.10a” as used herein may be:

[0633] deuterium (-D), —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, or a nitro group;

[0634] a C.sub.1-C.sub.60 alkyl group, a C.sub.2-C.sub.60 alkenyl group, a C.sub.2-C.sub.60 alkynyl group, or a C.sub.1-C.sub.60 alkoxy group, each unsubstituted or substituted with deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, a C.sub.3-C.sub.60 carbocyclic group, a C.sub.1-C.sub.60 heterocyclic group, a C.sub.6-C.sub.60 aryloxy group, a C.sub.6-C.sub.60 arylthio group, a C.sub.7-C.sub.60 aryl alkyl group, a C.sub.2-C.sub.60 heteroaryl alkyl group, —Si(Q.sub.11)(Q.sub.12)(Q.sub.13), —N(Q.sub.11)(Q.sub.12), —B(Q.sub.11)(Q.sub.12), —C(═O)(Q.sub.11), —S(═O).sub.2(Q.sub.11), —P(═O)(Q.sub.11)(Q.sub.12), or any combination thereof;

[0635] a C.sub.3-C.sub.60 carbocyclic group, a C.sub.1-C.sub.60 heterocyclic group, a C.sub.6-C.sub.60 aryloxy group, a C.sub.6-C.sub.60 arylthio group, a C.sub.7-C.sub.60 aryl alkyl group, or a C.sub.2-C.sub.60 heteroaryl alkyl group, each unsubstituted or substituted with deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, a C.sub.1-C.sub.60 alkyl group, a C.sub.2-C.sub.60 alkenyl group, a C.sub.2-C.sub.60 alkynyl group, a C.sub.1-C.sub.60 alkoxy group, a C.sub.3-C.sub.60 carbocyclic group, a C.sub.1-C.sub.60 heterocyclic group, a C.sub.6-C.sub.60 aryloxy group, a C.sub.6-C.sub.60 arylthio group, a C.sub.7-C.sub.60 aryl alkyl group, a C.sub.2-C.sub.60 heteroaryl alkyl group, —Si(Q.sub.21)(Q.sub.22)(Q.sub.23), —N(Q.sub.21)(Q.sub.22), —B(Q.sub.21)(Q.sub.22), —C(═O)(Q.sub.21), —S(═O).sub.2(Q.sub.21), —P(═O)(Q.sub.21)(Q.sub.22), or any combination thereof, or

[0636] —Si(Q.sub.31)(Q.sub.32)(Q.sub.33), —N(Q.sub.31)(Q.sub.32), —B(Q.sub.31)(Q.sub.32), —C(═O)(Q.sub.31), —S(═O).sub.2(Q.sub.31), or —P(═O)(Q.sub.31)(Q.sub.32).

[0637] Q.sub.1 to Q.sub.3, Q.sub.11 to Q.sub.13, Q.sub.21 to Q.sub.23 and Q.sub.31 to Q.sub.33 may each independently be: hydrogen; deuterium; —F; —Cl; —Br; —I; a hydroxyl group; a cyano group; a nitro group; a C.sub.1-C.sub.60 alkyl group; a C.sub.2-C.sub.60 alkenyl group; a C.sub.2-C.sub.60 alkynyl group; a C.sub.1-C.sub.60 alkoxy group; a C.sub.3-C.sub.60 carbocyclic group or a C.sub.1-C.sub.60 heterocyclic group, each unsubstituted or substituted with deuterium, —F, a cyano group, a C.sub.1-C.sub.60 alkyl group, a C.sub.1-C.sub.60 alkoxy group, a phenyl group, a biphenyl group, or any combination thereof, a C.sub.7-C.sub.60 aryl alkyl group; or a C.sub.2-C.sub.60 heteroaryl alkyl group.

[0638] The term “heteroatom” as used herein may be any atom other than a carbon atom or a hydrogen atom. Examples of the heteroatom may include O, S, N, P, Si, B, Ge, Se, or any combination thereof.

[0639] The term “third-row transition metal” as used herein may include hafnium (Hf), tantalum (Ta), tungsten (W), rhenium (Re), osmium (Os), iridium (Ir), platinum (Pt), and gold (Au).

[0640] The term “Ph” as used herein represents a phenyl group, the term “Me” as used herein represents a methyl group, the term “Et” as used herein represents an ethyl group, the terms “tert-Bu” or “Bu.sup.t” as used herein each represent a tert-butyl group, and the term “OMe” as used herein represents a methoxy group.

[0641] The term “biphenyl group” as used herein may be a phenyl group substituted with a phenyl group. For example, the “biphenyl group” may be a substituted phenyl group having a C.sub.6-C.sub.60 aryl group as a substituent.

[0642] The term “terphenyl group” as used herein may be a phenyl group substituted with a biphenyl group. For example, the “terphenyl group” may be “a substituted phenyl group” having a “C.sub.6-C.sub.60 aryl group substituted with a C.sub.6-C.sub.60 aryl group” as a substituent.

[0643] The symbols *, *′, *″, and *′″ as used herein, unless defined otherwise, refer to a binding site to an adjacent atom in a corresponding formula or moiety.

[0644] Hereinafter, compounds and a light-emitting device according to embodiments will be described in more detail with reference to Synthesis Examples and Examples. The wording “B was used instead of A” used in describing Synthesis Examples means that an amount of B used was identical to an amount of A used in terms of molar equivalents.

EXAMPLES

Synthesis Example 1: Synthesis of Compound 1

[0645] ##STR00193## ##STR00194##

[0646] (1) Synthesis of Intermediate [1-A]

[0647] 2-bromo-1,4-difluorobenzene (2.0 eq.), imidazole (1.0 eq.), and K.sub.3PO.sub.4 (2.0 eq.) were added to a reaction vessel, followed by suspension in dimethyl formamide (DMF, 0.25 molar (M)). The reaction mixture was heated to a temperature of 160° C. and stirred for 12 hours. Once the reaction was complete, the mixture was cooled to room temperature, and an extraction process was performed thereon by using distilled water and ethyl acetate. The extracted organic layer was washed using saturated NaCl aqueous solution and dried using magnesium sulfate. The residue from which the solvent was removed was separated by using column chromatography to thereby obtain Intermediate [1-A] (yield: 73%).

[0648] (2) Synthesis of Intermediate [1-B]

[0649] Intermediate [1-A] (1.0 eq.), carbazole (1.5 eq.), and K.sub.3PO.sub.4 (2.0 eq.) were added to a reaction vessel, followed by suspension in DMF (0.25 M). The reaction mixture was heated to a temperature of 160° C. and stirred for 12 hours. Once the reaction was complete, the mixture was cooled to room temperature, and an extraction process was performed thereon by using distilled water and ethyl acetate. The extracted organic layer was washed using saturated NaCl aqueous solution and dried using magnesium sulfate. The residue from which the solvent was removed was separated by using column chromatography to thereby obtain Intermediate [1-B](yield: 80%).

[0650] (3) Synthesis of Intermediate [1-C]

[0651] 3-fluoroacetophenone (2.0 eq.), Mg (2.0 eq.), and iodine (0.01 eq.) were added to a reaction vessel, followed by suspension in anhydrous tetrahydrofuran (THF, 0.5 M) in argon atmosphere. The reaction mixture was heated to a temperature of 60° C. and stirred for 2 hours. Intermediate [1-B] (1.0 eq.) was added dropwise slowed to the stirred mixture. The reaction mixture was stirred at a temperature of 60° C. for 12 hours. Once the reaction was complete, the reaction mixture was cooled to room temperature, and an ammonium chloride solution was added thereto, followed by extraction using ethyl acetate. The extracted organic layer was dried using magnesium sulfate. The residue from which the solvent was removed was separated by using column chromatography to thereby obtain Intermediate [1-C] (yield: 72%).

[0652] (4) Synthesis of Intermediate [1-D]

[0653] Intermediate [1-C] (1.0 eq.) was added to a reaction vessel, followed by suspension in methylene chloride (0.5 M). At room temperature, triflic acid (1.5 eq) was slowly added thereto dropwise to the reaction mixture. The reaction mixture was stirred at a temperature of 25° C. for 12 hours. Once the reaction was complete, neutralization using NaOH and ammonium chloride was carried out, followed by extraction using methylene chloride. The extracted organic layer was washed using saturated NaCl aqueous solution and dried using magnesium sulfate. The residue from which the solvent was removed was separated by using column chromatography to thereby obtain Intermediate [1-D] (yield: 85%).

[0654] (5) Synthesis of Intermediate [1-E]

[0655] Intermediate [1-E] was synthesized in the same manner as in Synthesis of Intermediate [1-A], except that Intermediate [1-D] was used instead of 2-bromo-1,4-difluorobenzene (yield: 82%).

[0656] (6) Synthesis of Intermediate [1-F]

[0657] Intermediate [1-E] (1.0 eq.) and iodomethane (10.0 eq.) were added to a reaction vessel, followed by suspension in toluene (0.1 M). The reaction mixture was heated to a temperature of 110° C. and stirred for 12 hours. Once the reaction was complete, the mixture was cooled to room temperature, and an extraction process was performed thereon by using distilled water and ethyl acetate. The extracted organic layer was dried using magnesium sulfate, and the solvent was removed therefrom to thereby obtain Intermediate [1-F] (yield: 90%).

[0658] (7) Synthesis of Intermediate [1-G]

[0659] Intermediate [1-F] (1.0 eq.) was added to a reaction vessel, followed by suspension onto a mixed solution of methanol and distilled water at a ratio of 2:1. The reaction mixture was sufficiently dissolved, and ammonium hexafluorophosphate (2.2 eq.) was slowly added thereto, followed by stirring the reaction solution at room temperature for 12 hours. Once the reaction was complete, the thus produced solid was filtered and washed using diethyl ether. The washed solid was dried to obtain Intermediate [1-G] (yield: 93%).

[0660] (8) Synthesis of Compound 1

[0661] Intermediate [1-G] (1.0 eq.), dichloro(1,5-cyclooctadiene)platinum (1.1 eq.), and sodium acetate (3.0 eq.) were suspended in 1,4-dioxane (0.1 M). The reaction mixture was heated to a temperature of 120° C. and stirred for 72 hours. Once the reaction was complete, the reaction mixture was cooled to room temperature, and an extraction process was performed thereon by using distilled water and ethyl acetate. The extracted organic layer was washed using saturated NaCl aqueous solution and dried using magnesium sulfate. The residue from which the solvent was removed was separated by using column chromatography to thereby obtain Compound 1 (yield: 32%).

Synthesis Example 2: Synthesis of Compound 11

[0662] ##STR00195## ##STR00196## ##STR00197##

[0663] (1) Synthesis of Intermediate [11-B]

[0664] Intermediate [11-B] was synthesized in the same manner as in Synthesis of Intermediate [1-B], except that 3-tert-Butyl-9H-carbazole was used instead of carbazole (yield: 78%).

[0665] (2) Synthesis of Intermediate [11-C]

[0666] Intermediate [11-C] was synthesized in the same manner as in Synthesis of Intermediate [1-C], except that Intermediate [11-B] was used instead of Intermediate [1-B](yield: 76%).

[0667] (3) Synthesis of Intermediate [11-D]

[0668] Intermediate [11-D] was synthesized in the same manner as in Synthesis of Intermediate [1-D], except that Intermediate [11-C] was used instead of Intermediate [1-C](yield: 80%).

[0669] (4) Synthesis of Intermediate [11-E]

[0670] Intermediate [11-E] was synthesized in the same manner as in Synthesis of Intermediate [1-E], except that Intermediate [11-D] was used instead of Intermediate [1-D](yield: 73%).

[0671] (5) Synthesis of Intermediate [11-F]

[0672] Intermediate [11-F] was synthesized in the same manner as in Synthesis of Intermediate [1-F], except that Intermediate [11-E] was used instead of Intermediate [1-E](yield: 85%).

[0673] (6) Synthesis of Intermediate [11-G]

[0674] Intermediate [11-G] was synthesized in the same manner as in Synthesis of Intermediate [1-G], except that Intermediate [11-F] was used instead of Intermediate [1-F](yield: 92%).

[0675] (7) Synthesis of Compound 11

[0676] Compound 11 was synthesized in the same manner as in Synthesis of Compound 1, except that Intermediate [11-G] was used instead of Intermediate [1-G] (yield: 36%).

Synthesis Example 3: Synthesis of Compound 71

[0677] ##STR00198## ##STR00199##

[0678] (1) Synthesis of Intermediate [71-A]

[0679] 1-bromo-4-fluoro-2-nitrobenzene (1.0 eq.), imidazole (1.2 eq.), and K.sub.3PO.sub.4 (2.0 eq.) were added to a reaction vessel, followed by suspension in DMF (0.25 M). The reaction mixture was heated to a temperature of 160° C. and stirred for 24 hours. Once the reaction was complete, the mixture was cooled to room temperature, and an extraction process was performed thereon by using distilled water and ethyl acetate. The extracted organic layer was washed using saturated NaCl aqueous solution and dried using magnesium sulfate. The residue from which the solvent was removed was separated by using column chromatography to thereby obtain Intermediate [71-A] (yield: 92%).

[0680] (2) Synthesis of Intermediate [71-B]

[0681] Intermediate [71-A] (1.0 eq.), carbazole (1.2 eq.), K.sub.2CO.sub.3 (2.0 eq.), CuI (0.1 eq.), and 1,10-phenanthroline (0.1 eq.) were added to a reaction vessel, followed by suspension in DMF (0.25 M). The reaction mixture was heated to a temperature of 160° C. and stirred for 24 hours. Once the reaction was complete, the mixture was cooled to room temperature, and an extraction process was performed thereon by using distilled water and ethyl acetate. The extracted organic layer was washed using saturated NaCl aqueous solution and dried using magnesium sulfate. The residue from which the solvent was removed was separated by using column chromatography to thereby obtain Intermediate [71-B] (yield: 73%).

[0682] (3) Synthesis of Intermediate [71-C]

[0683] Intermediate [71-B] (1.0 eq.) and triethylphosphite (6.0 eq.) were added to a reaction vessel, followed by suspension. The reaction mixture was heated to a temperature of 120° C. and stirred for 12 hours. Once the reaction was complete, the mixture was cooled to room temperature, and the solvent was removed therefrom under reduced pressure. The residue was extracted using distilled water and ethyl acetate. The extracted organic layer was washed using saturated NaCl aqueous solution and dried using magnesium sulfate. The residue from which the solvent was removed was separated by using column chromatography to thereby obtain Intermediate [71-C] (yield: 60%).

[0684] (4) Synthesis of Intermediate [71-D]

[0685] Intermediate [71-C] (1.0 eq.), 1,3-dibromobenzene (2.0 eq.), Pd.sub.2(dba).sub.3 (0.05 eq.), Sphos (0.075 eq.), and sodium tert-butoxide (2.0 eq.) were added to a reaction vessel, followed by suspension in toluene (0.1 M). The reaction mixture was heated to a temperature of 110° C. and stirred for 4 hours. Once the reaction was complete, the mixture was cooled to room temperature, and an extraction process was performed thereon by using distilled water and ethyl acetate. The extracted organic layer was washed using saturated NaCl aqueous solution and dried using magnesium sulfate. The residue from which the solvent was removed was separated by using column chromatography to thereby obtain Intermediate [71-D] (yield: 65%).

[0686] (5) Synthesis of Intermediate [71-E]

[0687] Intermediate [71-D] (1.0 eq.), imidazole (1.2 eq.), K.sub.2CO.sub.3 (2.0 eq.), CuI (0.1 eq.), and 1,10-phenanthroline (0.1 eq.) were added to a reaction vessel, followed by suspension in DMF (0.25 M). The reaction mixture was heated to a temperature of 160° C. and stirred for 24 hours. Once the reaction was complete, the mixture was cooled to room temperature, and an extraction process was performed thereon by using distilled water and ethyl acetate. The extracted organic layer was washed using saturated NaCl aqueous solution and dried using magnesium sulfate. The residue from which the solvent was removed was separated by using column chromatography to thereby obtain Intermediate [71-E] (yield: 76%).

[0688] (6) Synthesis of Intermediate [71-F]

[0689] Intermediate [71-F] was synthesized in the same manner as in Synthesis of Intermediate [1-F], except that Intermediate [71-E] was used instead of Intermediate [1-E](yield: 93%).

[0690] (7) Synthesis of Intermediate [71-G]

[0691] Intermediate [71-G] was synthesized in the same manner as in Synthesis of Intermediate [1-G], except that Intermediate [71-F] was used instead of Intermediate [1-F](yield: 90%).

[0692] 8) Synthesis of Compound 71

[0693] Compound 71 was synthesized in the same manner as in Synthesis of Compound 1, except that Intermediate [71-G] was used instead of Intermediate [1-G] (yield: 34%).

[0694] The .sup.1H nuclear magnetic resonance (NMR) and mass spectroscopy/fast atom bombardment (MS/FAB) results are shown in Table 1.

TABLE-US-00001 TABLE 1 MS/FAB Compound .sup.1H NMR (CDCl.sub.3, 400 MHz) found Calc. 1 2.28(s, 3H), 3.72(s, 6H), 7.07(t, 1H), 7.16-7.18(m, 698.18 698.69 2H), 7.27(m, 2H), 7.34-7.35(m, 2H), 7.44-7.45(m, 3H), 7.5l(d, 1H), 7.65(d, 1H), 7.72(d, 1H), 7.93(d, 1H), 8.09(d, 1H), 8.56(d, 1H) 11 1.42(s, 9H), 2.27(s, 3H), 3.71(s, 6H), 7.08(t, 1H), 754.24 754.80 7.11(d, 1H), 7.18(d, 1H), 7.28(d, 2H), 7.34(t, 1H), 7.44- 7.45(m, 3H), 7.5l(d, 1H), 7.66(d, 1H), 7.72(d, 1H), 7.86 (d, 1H), 8.09(d, 1H), 8.96(s, 1H) 71 3.72(s, 6H), 7.16-7.19(m, 2H), 7.24-7.27(m, 4H), 685.16 685.65 7.32-7.35(m, 3H), 7.41(d, 1H), 7.44(d, 2H), 7.69(d, 1H), 7.86(d, 1H), 7.94(d, 1H), 8.55(d, 1H)

[0695] Methods of synthesizing compounds other than the compounds synthesized in Synthesis Examples 1 to 3 may be easily understood to those skilled in the art by referring to the synthesis pathways and raw materials described above.

Example 1-1

[0696] As an anode, a 15 Ohms per square centimeter (Ω/cm.sup.2) (1,200 Å) ITO glass substrate (available from Corning Co., Ltd) was cut to a size of 50 millimeters (mm)×50 mm×0.7 mm, sonicated in isopropyl alcohol and pure water for 5 minutes in each solvent, cleaned with ultraviolet rays for 30 minutes, and with ozone, and was mounted on a vacuum deposition apparatus.

[0697] 2-TNATA was vacuum-deposited on the anode to form a hole injection layer having a thickness of 600 Å, and 4,4′-bis[N-(1-naphthyl)-N-phenylamino]biphenyl (hereinafter, referred as “NPB”) was vacuum-deposited on the hole injection layer to form a hole transport layer having a thickness of 300 Å.

[0698] Compound 1 (the first compound), Compound ETH68 (the second compound), and Compound HTH29 (the third compound) were vacuum-deposited on the hole transport layer to form an emission layer having a thickness of 400 Å. Here, the content of Compound 1 was 10 wt %, based on 100 wt % of the total weight of the emission layer, and the weight ratio of Compound ETH68 to Compound HTH29 was 3:7.

[0699] Compound ETH2 was deposited on the emission layer to form a hole blocking layer having a thickness of 50 Å, Alq.sub.3 was deposited on the hole blocking layer to form an electron transport layer having a thickness of 300 Å, LiF was vacuum-deposited on the electron transport layer to form an electron injection layer having a thickness of 10 Å, and A1 was vacuum-deposited on the electron injection layer to form a cathode having a thickness of 3,000 Å, thereby completing the manufacture of an organic light-emitting device.

##STR00200##

Examples 1-2 and 1-3 and Comparative Examples 1-1 to 1-3

[0700] Organic light-emitting devices were manufactured in the same manner as in Example 1-1, except that the first compound, the second compound, and the third compound as shown in Table 2 were used in the formation of the emission layer.

Evaluation Example 1

[0701] The driving voltage (V), luminescence efficiency (cd/A), maximum emission wavelength (nm), and lifespan (LT.sub.95) of the organic light-emitting devices of Examples 1-1 to 1-3 and Comparative Examples 1-1 to 1-3 at 1,000 cd/m.sup.2 were measured by using Keithley source-measure unit (SMIU) 236 and a luminance meter PR650. The results thereof are shown in Table 2. In Table 2, the lifespan (LT.sub.95) indicates a time (hour) for the luminance of each light-emitting device to decline to 95% of its initial luminance.

TABLE-US-00002 TABLE 2 Dopant Host Driving Luminescence Maximum Lifespan First Second Third Luminance voltage efficiency emission (LT.sub.95) compound compound compound (cd/m.sup.2) (V) (cd/A) wavelength (nm) (hours) Example 1-1 1 ETH68 HTH29 1000 4.3 20.1 457 87.0 Example 1-2 11 ETH68 HTH29 1000 4.2 20.8 458 86.9 Example 1-3 71 ETH68 HTH29 1000 4.2 22.1 464 90.2 Comparative A ETH68 HTH29 1000 4.3 17.8 465 84.1 Example 1-1 Comparative B ETH68 HTH29 1000 4.7 15.1 464 57.9 Example 1-2 Comparative C ETH68 HTH29 1000 5.1 12.2 474 13.8 Example 1-3

##STR00201##

[0702] Referring to the results of Table 2, the organic light-emitting devices of Examples 1-1 to 1-3 were found to have a low driving voltage, excellent luminescence efficiency, and lifespan characteristics and emit dark blue light.

Examples 2-1 to 2-3 and Comparative Examples 2-1 to 2-3

[0703] Organic light-emitting devices were manufactured in the same manner as in Example 1-1, except that the first compound, the second compound, and the third compound as shown in Table 3 were used to form the emission layer, a fourth compound was additionally used, a content of the first compound was 10 wt % based on the total content of (100 wt %) of the emission layer, a content of the fourth compound was 0.5 wt % based on the total content of (100 wt % o) of the emission layer, and the weight ratio of the second compound to third compound was adjusted to 3:7.

Evaluation Example 2

[0704] The driving voltage (V), luminescence efficiency (cd/A), maximum emission wavelength (nm), and lifespan (LT.sub.95) of the organic light-emitting devices of Examples 2-1 to 2-3 and Comparative Examples 2-1 to 2-3 at 1,000 cd/m.sup.2 were measured by using Keithley SMU 236 and a luminance meter PR650. The results thereof are shown in Table 3. In Table 3, the lifespan (LT.sub.95) indicates a time (hour) for the luminance of each light-emitting device to decline to 95% of its initial luminance.

TABLE-US-00003 TABLE 3 Ancillary dopant Host Dopant Driving Luminescence Lifespan First Second Third Fourth Luminance voltage efficiency Emission (LT.sub.95) compound compound compound compound (cd/m.sup.2) (V) (cd/A) wavelength (nm) (hours) Example 2-1 1 ETH68 HTH29 DFD2 1000 4.4 18.9 461 56.3 Example 2-2 11 ETH68 HTH29 DFD2 1000 4.4 18.1 461 54.9 Example 2-3 71 ETH68 HTH29 DFD2 1000 4.3 19.3 461 58.1 Comparative A ETH68 HTH29 DFD2 1000 4.5 16.7 461 49.9 Example 2-1 Comparative B ETH68 HTH29 DFD2 1000 4.7 13.5 462 34.1 Example 2-2 Comparative C ETH68 HTH29 DFD2 1000 5.0 10.5. 472 10.1 Example 2-3

[0705] Referring to the results of Table 3, the organic light-emitting devices of Examples 2-1 to 2-3 were found to have a low driving voltage, excellent luminescence efficiency, and lifespan characteristics and emit dark blue light.

[0706] Embodiments have been disclosed herein, and although terms are employed, they are used and are to be interpreted in a generic and descriptive sense only and not for purpose of limitation. In some instances, as would be apparent by one of ordinary skill in the art, features, characteristics, and/or elements described in connection with an embodiment may be used singly or in combination with features, characteristics, and/or elements described in connection with other embodiments unless otherwise specifically indicated. Accordingly, it will be understood by those of ordinary skill in the art that various changes in form and details may be made without departing from the spirit and scope of the disclosure as set forth in the claims.