LIGHT-EMITTING DEVICE AND ELECTRONIC APPARATUS INCLUDING THE SAME

Abstract

Embodiments provide a light-emitting device, an electronic apparatus that includes the light-emitting device, and an electronic equipment that includes light-emitting device. The light-emitting device includes a first electrode, a second electrode facing the first electrode, and an interlayer between the first electrode and the second electrode. The interlayer includes an emission layer, a first compound that is a hole-transporting compound, a second compound that is an electron-transporting compound, a third compound including at least one nitrogen atom (N) as a ring-forming atom, and a fourth compound that is a nitrogen-containing compound.

Claims

1. A light-emitting device comprising: a first electrode; a second electrode facing the first electrode; and an interlayer between the first electrode and the second electrode, wherein the interlayer comprises: an emission layer; a first compound that is a hole-transporting compound; a second compound that is an electron-transporting compound; a third compound comprising at least one nitrogen atom (N) as a ring-forming atom; and a fourth compound that is a nitrogen-containing compound, the fourth compound has a difference (E.sub.ST) between a lowest excited singlet state energy level and a lowest excited triplet energy level greater than or equal to about 0.4 eV, and the light-emitting device satisfies Condition 1 or Condition 2:
K.sup.FRET>K.sub.r.sup.s[Condition 1] wherein in Condition 1, K.sup.FRET is a Forster resonance energy transfer (FRET) rate constant between the third compound and the fourth compound, and K.sub.r.sup.s is a luminescence rate constant of the third compound, and
R.sub.0>R.sub.DA[Condition 2] wherein in Condition 2, R.sub.0 is a Forster radius between the third compound and the fourth compound, and R.sub.DA is a distance between a molecule of the third compound and a molecule of the fourth compound.

2. The light-emitting device of claim 1, wherein the emission layer includes the first compound, the second compound, the third compound, and the fourth compound.

3. The light-emitting device of claim 1, wherein the first compound and the second compound form an exciplex host.

4. The light-emitting device of claim 1, wherein the third compound is a delayed fluorescence material.

5. The light-emitting device of claim 1, wherein the fourth compound is a prompt fluorescence dopant.

6. The light-emitting device of claim 1, wherein a difference between a highest occupied molecular orbital (HOMO) energy value of the first compound and a HOMO energy value of the second compound is greater than or equal to about 0.2 eV.

7. The light-emitting device of claim 1, wherein a difference between a lowest unoccupied molecular orbital (LUMO) energy value of the first compound and a LUMO energy value of the second compound is greater than or equal to about 0.2 eV.

8. The light-emitting device of claim 1, wherein the light-emitting device satisfies Condition 1 and Condition 2.

9. The light-emitting device of claim 1, wherein the light-emitting device further satisfies Condition 4 or Condition 5:
K.sup.FRET>K.sup.ISC[Condition 4]
K.sup.RISC>K.sup.DET[Condition 5] wherein in Conditions 4 and 5, K.sup.FRET is a FRET rate constant between the third compound and the fourth compound, K.sup.ISC is an intersystem crossing (ISC) rate constant of the third compound, K.sup.RISC is a reverse intersystem crossing (RISC) rate constant of the third compound, and K.sup.DET is a Dexter electron transfer (DET) rate constant between the third compound and the fourth compound.

10. The light-emitting device of claim 1, wherein the first compound is represented by Formula 1: ##STR00213## wherein in Formula 1, R.sub.1, R.sub.2, and Ar.sub.1 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 that is unsubstituted or substituted with at least one R.sub.10a, a C.sub.2-C.sub.60 alkenyl group that is unsubstituted or substituted with at least one R.sub.10a, a C.sub.2-C.sub.60 alkynyl group that is unsubstituted or substituted with at least one R.sub.10a, a C.sub.1-C.sub.60 alkoxy group that is unsubstituted or substituted with at least one R.sub.10a, a C.sub.3-C.sub.60 carbocyclic group that is unsubstituted or substituted with at least one R.sub.10a, a C.sub.1-C.sub.60 heterocyclic group that is 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), L.sub.1 is a C.sub.3-C.sub.60 carbocyclic group that is unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group that is unsubstituted or substituted with at least one R.sub.10a, a1 and a2 are each independently an integer from 1 to 4, b1 is an integer from 0 to 3, R.sub.10a is: deuterium, F, C.sub.1, 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, 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 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, a C.sub.6-C.sub.60 arylthio group, a C.sub.7-C.sub.60 arylalkyl group, or a C.sub.2-C.sub.60 heteroarylalkyl 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.5-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 arylalkyl group, a C.sub.2-C.sub.60 heteroarylalkyl 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), and 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; or 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 a combination thereof.

11. The light-emitting device of claim 1, wherein the second compound is represented by Formula 2: ##STR00214## wherein in Formula 2, Ar.sub.11 to Ar.sub.13 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 that is unsubstituted or substituted with at least one R.sub.10a, a C.sub.2-C.sub.60 alkenyl group that is unsubstituted or substituted with at least one R.sub.10a, a C.sub.2-C.sub.60 alkynyl group that is unsubstituted or substituted with at least one R.sub.10a, a C.sub.1-C.sub.60 alkoxy group that is unsubstituted or substituted with at least one R.sub.10a, a C.sub.3-C.sub.60 carbocyclic group that is unsubstituted or substituted with at least one R.sub.10a, a C.sub.1-C.sub.60 heterocyclic group that is 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), L.sub.11 to L.sub.13 are each independently a C.sub.3-C.sub.60 carbocyclic group that is unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group that is unsubstituted or substituted with at least one R.sub.10a, b11 to b13 are each independently an integer from 0 to 3, 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.5-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 arylalkyl group, a C.sub.2-C.sub.60 heteroarylalkyl 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, a C.sub.6-C.sub.60 arylthio group, a C.sub.7-C.sub.60 arylalkyl group, or a C.sub.2-C.sub.60 heteroarylalkyl 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 arylalkyl group, a C.sub.2-C.sub.60 heteroarylalkyl 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), and 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; or 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 a combination thereof.

12. The light-emitting device of claim 1, wherein the third compound is represented by Formula 3-1 or Formula 3-2: ##STR00215## wherein in Formulae 3-1 and 3-2, X.sub.31 and X.sub.32 are each independently a single bond, O, S, B(R), N(R), P(R), C(R)(R), Si(R)(R), Ge(R)(R), C(O), N(R)(R), or P(R)(R), R and R are optionally bonded to each other to form a C.sub.3-C.sub.60 carbocyclic group that is unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group that is unsubstituted or substituted with at least one R.sub.10a, a31 is an integer from 1 to 6, a32 is an integer from 0 to 6, Ar.sub.31 and Ar.sub.32 are each independently a C.sub.3-C.sub.60 carbocyclic group that is unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group that is unsubstituted or substituted with at least one R.sub.10a, b31 and b32 are each independently an integer from 1 to 6, c31 and c32 are each independently an integer from 0 to 8, T.sub.31 is a single bond, a double bond, *N(R.sub.33)-*, *B(R.sub.33)-*, *P(R.sub.33)-*, *C(R.sub.33)(R.sub.34)-*, *Si(R.sub.33)(R.sub.34)-*, *-Ge(R.sub.33)(R.sub.34)-*, *S*, *Se-*, *-O**, *C(O)-*, *S(O)-*, *S(O).sub.2-*, *C(R.sub.33)**, *C(R.sub.33)-*, *C(R.sub.33)C(R.sub.34)-*, *C(S)-*, or *-CC-**, n31 is an integer from 1 to 4, when n31 is 2 or more, two or more of T.sub.31 are optionally bonded with Ar.sub.31 and Ar.sub.32 to form a ring, R.sub.31 to R.sub.34, R, and R 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 that is unsubstituted or substituted with at least one R.sub.10a, a C.sub.2-C.sub.60 alkenyl group that is unsubstituted or substituted with at least one R.sub.10a, a C.sub.2-C.sub.60 alkynyl group that is unsubstituted or substituted with at least one R.sub.10a, a C.sub.1-C.sub.60 alkoxy group that is unsubstituted or substituted with at least one R.sub.10a, a C.sub.3-C.sub.60 carbocyclic group that is unsubstituted or substituted with at least one R.sub.10a, a C.sub.1-C.sub.60 heterocyclic group that is 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), 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, a C.sub.7-C.sub.60 arylalkyl group, a C.sub.2-C.sub.60 heteroarylalkyl 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, a C.sub.6-C.sub.60 arylthio group, a C.sub.7-C.sub.60 arylalkyl group, or a C.sub.2-C.sub.60 heteroarylalkyl 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.5-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 arylalkyl group, a C.sub.2-C.sub.60 heteroarylalkyl 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), and 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; or 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 a combination thereof.

13. The light-emitting device of claim 12, wherein T.sub.31 is a single bond, *N(R.sub.33)-*, *C(R.sub.33)(R.sub.34)-*, *Si(R.sub.33)(R.sub.34)-*, Ge(R.sub.33)(R.sub.34)-*, *S*, *-O**, *C(O)-*, *S(O)-*, or *S(O).sub.2-*.

14. The light-emitting device of claim 12, wherein the third compound is one of Compounds DA-01 to DA-10: ##STR00216## ##STR00217##

15. The light-emitting device of claim 1, wherein the fourth compound is represented by Formula 4: ##STR00218## wherein in Formula 4, Ar.sub.41 to Ar.sub.44 are each independently a C.sub.3-C.sub.60 carbocyclic group that is unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group that is unsubstituted or substituted with at least one R.sub.10a, a41 is an integer from 1 to 4, c41 is an integer from 1 to 8, R.sub.41 is hydrogen, deuterium, F, Cl, Br,-I, a hydroxyl group, a cyano group, a nitro group, a C.sub.1-C.sub.60 alkyl group that is unsubstituted or substituted with at least one R.sub.10a, a C.sub.2-C.sub.60 alkenyl group that is unsubstituted or substituted with at least one R.sub.10a, a C.sub.2-C.sub.60 alkynyl group that is unsubstituted or substituted with at least one R.sub.10a, a C.sub.1-C.sub.60 alkoxy group that is unsubstituted or substituted with at least one R.sub.10a, a C.sub.3-C.sub.60 carbocyclic group that is unsubstituted or substituted with at least one R.sub.10a, a C.sub.1-C.sub.60 heterocyclic group that is 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), 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, a C.sub.7-C.sub.60 arylalkyl group, a C.sub.2-C.sub.60 heteroarylalkyl 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, a C.sub.6-C.sub.60 arylthio group, a C.sub.7-C.sub.60 arylalkyl group, or a C.sub.2-C.sub.60 heteroarylalkyl 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 arylalkyl group, a C.sub.2-C.sub.60 heteroarylalkyl 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), and 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; or 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 a combination thereof.

16. The light-emitting device of claim 1, wherein the fourth compound is one of Compounds D-01 to D-04: ##STR00219##

17. An electronic apparatus comprising the light-emitting device of claim 1.

18. The electronic apparatus of claim 17, further comprising a color filter, a color conversion layer, a touch screen layer, a polarizing layer, or a combination thereof.

19. An electronic equipment comprising the light-emitting device of claim 1.

20. The electronic equipment of claim 19, wherein the electronic equipment is a flat panel display, a curved display, a computer monitor, a medical monitor, a television, a billboard, an indoor light, an outdoor light, a signal light, a head-up display, a fully transparent display, a partially transparent display, a flexible display, a rollable display, a foldable display, a stretchable display, a laser printer, a telephone, a mobile phone, a tablet personal computer, a phablet, a personal digital assistant (PDA), a wearable device, a laptop computer, a digital camera, a camcorder, a viewfinder, a micro display, a three-dimensional (3D) display, a virtual reality display, an augmented reality display, a vehicle, a video wall including multiple displays tiled together, a theater screen, a stadium screen, a phototherapy device, or a signboard.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0039] The accompanying drawings are included to provide a further understanding of the embodiments, and are incorporated in and constitute a part of this specification. The drawings illustrate embodiments of the disclosure and principles thereof. The above and other aspects and features of the disclosure will be more apparent by describing in detail embodiments thereof with reference to the accompanying drawings, in which:

[0040] FIG. 1 is a schematic cross-sectional view of a light-emitting device according to an embodiment;

[0041] FIG. 2 is a schematic cross-sectional view of an electronic apparatus according to an embodiment;

[0042] FIG. 3 is a schematic cross-sectional view of an electronic apparatus according to another embodiment;

[0043] FIG. 4 is a schematic perspective view of an electronic equipment including a light-emitting device, according to another embodiment;

[0044] FIG. 5 is a schematic perspective view of an exterior of a vehicle as an electronic equipment including a light-emitting device, according to an embodiment;

[0045] FIGS. 6A to 6C are each a schematic diagram of an interior of a vehicle according to embodiments; and

[0046] FIG. 7 is a graph of a time-resolved photoluminescence (TRPL) spectrum of a light-emitting device, according to an embodiment.

DETAILED DESCRIPTION OF THE EMBODIMENTS

[0047] 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.

[0048] In the drawings, the sizes, thicknesses, ratios, and dimensions of the elements may be exaggerated for ease of description and for clarity. Like reference numbers and/or like reference characters refer to like elements throughout.

[0049] 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.

[0050] 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.

[0051] 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.

[0052] 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.

[0053] 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 consisting of for the purpose of its meaning and interpretation. For example, at least one of A, B, and C may be understood to mean A only, B only, C only, or any combination of two or more of A, B, and C, such as ABC, ACC, BC, or CC. 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.

[0054] 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.

[0055] 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.

[0056] 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 (for example, 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.

[0057] 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.

[0058] 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.

[0059] A light-emitting device according to an embodiment may include: [0060] a first electrode; [0061] a second electrode facing the first electrode; and [0062] an interlayer between the first electrode and the second electrode, wherein [0063] the interlayer may include an emission layer, a first compound that is a hole-transporting compound, a second compound that is an electron-transporting compound, a third compound including at least one nitrogen atom (N) as a ring-forming atom, and a fourth compound that is a nitrogen-containing compound, [0064] the fourth compound may have a difference (E.sub.ST) between a lowest excited singlet state energy level and a lowest excited triplet energy level greater than or equal to about 0.4 eV, and [0065] the light-emitting device satisfies Condition 1 or Condition 2:

K.sup.FRET>K.sub.r.sup.s[Condition 1]

[0066] In Condition 1, [0067] K.sup.FRET may be a Forster resonance energy transfer (FRET) rate constant between the third compound and the fourth compound, and

[0068] K.sub.r.sup.s may be a luminescence rate constant of the third compound, and

R.sub.0>R.sub.DA[Condition 2] [0069] in Condition 2, [0070] R.sub.0 may be a Forster radius between the third compound and the fourth compound, and

[0071] R.sub.DA may be a distance between a molecule of the third compound and a molecule of the fourth compound.

[0072] In an embodiment, in Condition 2, R.sub.DA may be a measurement of a distance between a triplet state distribution position of the third compound and a singlet state distribution position of the fourth compound.

[0073] In an embodiment, the first electrode may be an anode, [0074] the second electrode may be a cathode, [0075] the interlayer may further include a hole transport region between the first electrode and the emission layer, and an electron transport region between the emission layer and the second electrode, [0076] the hole transport region may include a hole injection layer, a hole transport layer, an emission auxiliary layer, an electron blocking layer, or any combination thereof, and [0077] the electron transport region may include a hole blocking layer, an electron transport layer, an electron injection layer, an electron control layer, or any combination thereof.

[0078] In an embodiment, the emission layer may include the first compound, the second compound, the third compound, and the fourth compound.

[0079] In an embodiment, the first compound and the second compound may form an exciplex host.

[0080] In an embodiment, the third compound may be a sensitizer.

[0081] In an embodiment, the third compound may be a delayed fluorescence material.

[0082] In an embodiment, the fourth compound may be a dopant.

[0083] In an embodiment, the fourth compound may be a prompt fluorescence dopant.

[0084] In an embodiment, a difference between a highest occupied molecular orbital (HOMO) energy value of the first compound and a HOMO energy value of the second compound may be greater than or equal to about 0.2 eV.

[0085] In an embodiment, a difference between a lowest unoccupied molecular orbital (LUMO) energy value of the first compound and a LUMO energy value of the second compound may be greater than or equal to about 0.2 eV.

[0086] In an embodiment, the light-emitting device may satisfy Condition 1 and Condition 2.

[0087] In an embodiment, the light-emitting device may further satisfy Condition 3.

E(T.sup.1).sub.H>E(T.sup.1).sub.3>E(T.sup.1).sub.4[Condition 3]

[0088] In Condition 3, [0089] E(T.sup.1).sub.H may be a lowest excited triplet energy level of excitons of the first compound and the second compound, [0090] E(T.sup.1): may be a lowest excited triplet energy level of the third compound, and [0091] E(T.sup.1).sub.4 may be a lowest excited triplet energy level of the fourth compound.

[0092] In an embodiment, energy may be transferred from an exciplex of the first compound and the second compound to the third compound, and energy may be transferred from the third compound to the fourth compound.

[0093] In an embodiment, the light-emitting device may further satisfy Condition 4.

K.sup.FRET>K.sup.ISC[Condition 4]

[0094] In Condition 4, [0095] K.sup.FRET may be a Forster resonance energy transfer (FRET) rate constant between the third compound and the fourth compound, and [0096] K.sup.ISC may be an intersystem crossing (ISC) rate constant of the third compound. In an embodiment, the light-emitting device may further satisfy Condition 5.

K.sup.RISC>K.sup.DET[Condition 5]

[0097] In Condition 5, [0098] K.sup.RISC may be a reverse intersystem crossing (RISC) rate constant of the third compound, and [0099] K.sup.DET may be a Dexter electron transfer (DET) rate constant between the third compound and the fourth compound.

[0100] In an embodiment, an amplitude within the time-resolved photoluminescence (TRPL) spectrum of the third compound may be greater than an amplitude within the TRPL spectrum of each of the first compound to the fourth compound.

[0101] In an embodiment, the fourth compound may have a difference (E.sub.ST) between the lowest excited singlet state energy level and the lowest excited triplet energy level greater than or equal to about 0.4 eV. For example, the fourth compound may have a difference (E.sub.ST) between the lowest excited singlet state energy level and the lowest excited triplet energy level greater than or equal to about 0.5 eV. For example, the fourth compound may have a difference (E.sub.ST) between the lowest excited singlet state energy level and the lowest excited triplet energy level greater than or equal to about 0.6 eV. For example, the fourth compound may have a difference (E.sub.ST) between the lowest excited singlet state energy level and the lowest excited triplet energy level greater than or equal to about 0.7 eV.

[0102] In an embodiment, the first compound may be represented by Formula 1:

##STR00001## [0103] In Formula 1, [0104] R.sub.1, R.sub.2, and Ar.sub.1 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 that is unsubstituted or substituted with at least one R.sub.10a, a C.sub.2-C.sub.60 alkenyl group that is unsubstituted or substituted with at least one R.sub.10a, a C.sub.2-C.sub.60 alkynyl group that is unsubstituted or substituted with at least one R.sub.10a, a C.sub.1-C.sub.60 alkoxy group that is unsubstituted or substituted with at least one R.sub.10a, a C.sub.3-C.sub.60 carbocyclic group that is unsubstituted or substituted with at least one R.sub.10a, a C.sub.1-C.sub.60 heterocyclic group that is 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), [0105] L.sub.1 may be a C.sub.3-C.sub.60 carbocyclic group that is unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group that is unsubstituted or substituted with at least one R.sub.10a, [0106] a1 and a2 may each independently be an integer from 1 to 4, [0107] b1 may be an integer from 0 to 3, [0108] R.sub.10a may be: [0109] deuterium, F, Cl, Br,-I, a hydroxyl group, a cyano group, or a nitro group; [0110] 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.5-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 arylalkyl group, a C.sub.2-C.sub.60 heteroarylalkyl 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; [0111] 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 arylalkyl group, or a C.sub.2-C.sub.60 heteroarylalkyl 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 arylalkyl group, a C.sub.2-C.sub.60 heteroarylalkyl 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 [0112] 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), and [0113] 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; or 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.

[0114] In an embodiment, R.sub.1, R.sub.2, and Ar.sub.1 may each independently be hydrogen, deuterium, or a group represented by one of Formulae 2a to 2c:

##STR00002##

[0115] In Formulae 2a to 2c, [0116] H.sub.1 may be N(R.sub.100), O, or S, [0117] Z.sub.1 to Z.sub.5 and R.sub.100 may each independently be the same as described in connection with R.sub.1, [0118] az1 may be an integer from 0 to 5, [0119] az2 and az3 may each independently be an integer from 0 to 4, [0120] az4 and az5 may each independently be an integer from 0 to 3, and [0121] * indicates a binding site to a neighboring atom.

[0122] In an embodiment, L.sub.1 may be a group represented by one of Formulae 3a to 3c:

##STR00003##

[0123] In Formulae 3a to 3c, [0124] Z.sub.6 to Z.sub.9 may each independently be the same as described in connection with R.sub.1, [0125] az6 may be an integer from 0 to 4, [0126] az7 and az8 may each independently be an integer from 0 to 7, and [0127] * and ** each indicate a binding site to a neighboring atom.

[0128] In an embodiment, the first compound may be one of Compounds HT-01 to HT-09:

##STR00004## ##STR00005## ##STR00006##

[0129] In an embodiment, the second compound may be represented by Formula 2:

##STR00007##

[0130] In Formula 2, [0131] Ar.sub.11 to Ar.sub.13 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 that is unsubstituted or substituted with at least one R.sub.10a, a C.sub.2-C.sub.60 alkenyl group that is unsubstituted or substituted with at least one R.sub.10a, a C.sub.2-C.sub.60 alkynyl group that is unsubstituted or substituted with at least one R.sub.10a, a C.sub.1-C.sub.60 alkoxy group that is unsubstituted or substituted with at least one R.sub.10a, a C.sub.3-C.sub.60 carbocyclic group that is unsubstituted or substituted with at least one R.sub.10a, a C.sub.1-C.sub.60 heterocyclic group that is 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), [0132] L.sub.11 to L.sub.13 may each independently be a C.sub.3-C.sub.60 carbocyclic group that is unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group that is unsubstituted or substituted with at least one R.sub.10a, [0133] b.sub.11 to b.sub.13 may each independently be an integer from 0 to 3, [0134] R.sub.10a may be: [0135] deuterium, F, Cl, Br,-I, a hydroxyl group, a cyano group, or a nitro group; [0136] 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.5-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 arylalkyl group, a C.sub.2-C.sub.60 heteroarylalkyl 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; [0137] 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 arylalkyl group, or a C.sub.2-C.sub.60 heteroarylalkyl 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 arylalkyl group, a C.sub.2-C.sub.60 heteroarylalkyl 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 [0138] 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), and [0139] 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; or 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.

[0140] In an embodiment, Ar.sub.11 to Ar.sub.13 may each independently be hydrogen, deuterium, or a group represented by one of Formulae 4a to 4e:

##STR00008## [0141] In Formulae 4a to 4e, [0142] Z.sub.10 to Z.sub.19 may each independently be the same as described in connection with R.sub.1, [0143] az17 and az18 may each independently be an integer from 0 to 7, [0144] az19 may be an integer from 0 to 5, and [0145] * indicates a binding site to a neighboring atom.

[0146] In an embodiment, L.sub.11 to L.sub.13 may each independently be a group represented by Formula 5a:

##STR00009##

[0147] In Formula 5a, [0148] Z.sub.20 may be the same as described in connection with R.sub.1, [0149] az20 may be an integer from 0 to 4, and [0150] * and * each indicate a binding site to a neighboring atom.

[0151] In an embodiment, the second compound may be one of Compounds ET01 to ET012.

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

[0152] In an embodiment, the third compound may be represented by Formula 3-1 or Formula 3-2:

##STR00013##

[0153] In Formulae 3-1 and 3-2, [0154] X.sub.31 and X.sub.32 may each independently be a single bond, O, S, B(R), N(R), P(R), C(R)(R), Si(R)(R), Ge(R)(R), C(O), N(R)(R), or P(R)(R), [0155] R and R may optionally be bonded to each other to form a C.sub.3-C.sub.60 carbocyclic group that is unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group that is unsubstituted or substituted with at least one R.sub.10a, [0156] a31 may be an integer from 1 to 6, [0157] a32 may be an integer from 0 to 6, [0158] Ar.sub.31 and Ar.sub.32 may each independently be a C.sub.5-C.sub.60 carbocyclic group that is unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group that is unsubstituted or substituted with at least one R.sub.10a, [0159] b31 and b32 may each independently be an integer from 1 to 6, [0160] c31 and c32 are each independently an integer from 0 to 8, [0161] T.sub.31 may be a single bond, a double bond, *N(R.sub.33)*, *B(R.sub.33)*, *P(R.sub.33)*, C(R.sub.3)(R.sub.34)-*, *Si(R.sub.3)(R.sub.34)-*, *-Ge(R.sub.33)(R.sub.34)-*, *S*, *Se-*, *-O*, *C(O)-*, *S(O)-*, *S(O).sub.2-*, *C(R.sub.33)**, *C(R.sub.33)-*, *C(R.sub.33)C(R.sub.34)-*, *C(S)-*, or *-CC-*, [0162] n31 may be an integer from 1 to 4, [0163] when n31 is 2 or more, two or more of T.sub.31 may optionally be bonded with Ar.sub.31 and Ar.sub.32 to form a ring, [0164] R.sub.31 to R.sub.34, R, and R 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 that is unsubstituted or substituted with at least one R.sub.10a, a C.sub.2-C.sub.60 alkenyl group that is unsubstituted or substituted with at least one R.sub.10a, a C.sub.2-C.sub.60 alkynyl group that is unsubstituted or substituted with at least one R.sub.10a, a C.sub.1-C.sub.60 alkoxy group that is unsubstituted or substituted with at least one R.sub.10a, a C.sub.3-C.sub.60 carbocyclic group that is unsubstituted or substituted with at least one R.sub.10a, a C.sub.1-C.sub.60 heterocyclic group that is 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), [0165] R.sub.10a may be: [0166] deuterium, F, Cl, Br,-I, a hydroxyl group, a cyano group, or a nitro group; [0167] 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 arylalkyl group, a C.sub.2-C.sub.60 heteroarylalkyl 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; [0168] 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 arylalkyl group, or a C.sub.2-C.sub.60 heteroarylalkyl 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 arylalkyl group, a C.sub.2-C.sub.60 heteroarylalkyl 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 [0169] 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), and [0170] 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; or 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.

[0171] In an embodiment, X.sub.31 and X.sub.32 may each independently be a single bond, O, C(R)(R), Si(R)(R), or N(R)(R).

[0172] In an embodiment, T.sub.31 may be a single bond, *N(R.sub.33)-*, *C(R.sub.33)(R.sub.34)-*, *Si(R.sub.33) (R.sub.34)-*, Ge(R.sub.33)(R.sub.34)-*, *S*, *-O**, *C(O)-*, *S(O)-*, or *S(O).sub.2-*.

[0173] In an embodiment, the third compound may be one of Compounds DA-01 to DA-10.

##STR00014## ##STR00015##

[0174] In an embodiment, the fourth compound may be represented by Formula 4:

##STR00016##

[0175] In Formula 4, [0176] Ar.sub.41 to Ar.sub.44 may each independently be a C.sub.3-C.sub.60 carbocyclic group that is unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group that is unsubstituted or substituted with at least one R.sub.10a, [0177] a41 may be an integer from 1 to 4, [0178] c41 may be an integer from 1 to 8, [0179] R.sub.41 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 that is unsubstituted or substituted with at least one R.sub.10a, a C.sub.2-C.sub.60 alkenyl group that is unsubstituted or substituted with at least one R.sub.10a, a C.sub.2-C.sub.60 alkynyl group that is unsubstituted or substituted with at least one R.sub.10a, a C.sub.1-C.sub.60 alkoxy group that is unsubstituted or substituted with at least one R.sub.10a, a C.sub.5-C.sub.60 carbocyclic group that is unsubstituted or substituted with at least one R.sub.10a, a C.sub.1-C.sub.60 heterocyclic group that is 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), [0180] R.sub.10a may be: [0181] deuterium, F, Cl, Br,-I, a hydroxyl group, a cyano group, or a nitro group; [0182] 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 arylalkyl group, a C.sub.2-C.sub.60 heteroarylalkyl 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; [0183] 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 arylalkyl group, or a C.sub.2-C.sub.60 heteroarylalkyl 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.5-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 arylalkyl group, a C.sub.2-C.sub.60 heteroarylalkyl 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 [0184] 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), and [0185] 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; or 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.

[0186] In an embodiment, Ar.sub.41 to Ar.sub.44 may each independently be: [0187] 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 indeno phenanthrene group, or an indenoanthracene group; or [0188] 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 indeno phenanthrene group, or an indenoanthracene 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, or any combination thereof.

[0189] In an embodiment, the fourth compound may be one of Compounds D-01 to D-04.

##STR00017##

[0190] By satisfying Condition 1 or Condition 2, the light-emitting device may further facilitate energy transfer between the third compound and the fourth compound.

[0191] Therefore, the light-emitting device may have improved color purity, improved efficiency, and improved lifespan characteristics.

K.sup.FRET>K.sub.r.sup.s[Condition 1]

[0192] In Condition 1, [0193] K.sup.FRET may be a Forster resonance energy transfer (FRET) rate constant between the third compound and the fourth compound, and [0194] K.sub.r.sup.s may be a luminescence rate constant of the third compound.

R.sub.0>R.sub.DA[Condition 2]

[0195] In Condition 2, [0196] R.sub.0 may be a Forster radius between the third compound and the fourth compound, and [0197] R.sub.DA may be a distance between a molecule of the third compound and a molecule of the fourth compound.

[0198] When the third compound is represented by one of Formulae 3-1 and 2-1 and when the fourth compound is represented by Formula 4, the luminescence efficiency and lifespan characteristics of the light-emitting device may be further improved.

[0199] A method of manufacturing the light-emitting device may be recognizable by one of ordinary skill in the art by referring to then Synthesis Examples and/or Examples provided below.

[0200] In an embodiment, the light-emitting device may further include: [0201] a first capping layer outside the first electrode; and [0202] a second capping layer outside the second electrode.

[0203] In an embodiment, the emission layer may include a host and a dopant.

[0204] In an embodiment, the emission layer may emit red light, green light, or blue light.

[0205] In an embodiment, the dopant may be a phosphorescent dopant or a delayed fluorescence dopant.

[0206] In an embodiment, the host may include a first host including at least one electron-donating group and a second host including at least one electron-withdrawing group.

[0207] In an embodiment, the emission layer may further include a sensitizer.

[0208] In an embodiment, the emission layer may include a delayed fluorescence material.

[0209] In an embodiment, the emission layer may emit red light, green light, or blue light.

[0210] In an embodiment, the emission layer may further include a first host and a second host, wherein the first host may be a hole-transporting compound including at least one electron-donating group, and the second host may be an electron-transporting host including at least one electron-withdrawing group.

[0211] In an embodiment, the first host may include the first compound, and the second host may include the second compound.

[0212] In an embodiment, the emission layer may further include a sensitizer, wherein the sensitizer may serve as, for example, a phosphorescent sensitizer, and the sensitizer may include the third compound.

[0213] In an embodiment, the third compound may not emit light.

[0214] In an embodiment, the emission layer may further include at least one of an auxiliary dopant and a sensitizer.

[0215] In an embodiment, the auxiliary dopant and the sensitizer may each independently be an organometallic compound including platinum and a tetradentate ligand bonded to platinum, wherein the tetradentate ligand may include a carbene moiety chemically bonded to the platinum. For example, the auxiliary dopant and/or the sensitizer may include the third compound.

[0216] In an embodiment, the first host and the second host may serve as an exciplex host.

[0217] The term electron-donating group may refer to any moiety having an ability to donate electrons, and for example, may be a electron-rich C.sub.3-C.sub.60 cyclic group or an amine group, but embodiments are not limited thereto. The electron-donating group may refer to a cyclic group other than a electron-deficient nitrogen-containing C.sub.1-C.sub.60 cyclic group.

[0218] The term electron-withdrawing group may refer to any moiety having an ability to withdraw electrons, and for example, may be F, CFH.sub.2, CF.sub.2H, CF.sub.3, CN, NO.sub.2, a electron-deficient nitrogen-containing C.sub.1-C.sub.60 cyclic group, or any combination thereof. However, embodiments are not limited thereto.

[0219] Regarding a luminescence pathway in the light-emitting device according to an embodiment, the first host and the second host may form an exciton (1st step), the energy of the exciton may be transferred to the third compound (2nd step), and the energy may be transferred from the third compound to the organometallic compound (3rd step).

[0220] In an embodiment, an amount of the third compound in the emission layer may be more than 0 parts by weight and less than 50 parts by weight, based on a total of 100 parts by weight of the emission layer.

[0221] In an embodiment, the first host may include at least one carbazole moiety, and the second host may include at least one azine moiety.

[0222] In an embodiment, the first host may be represented by Formula 301-1A or Formula 301-2A:

##STR00018##

[0223] In Formulae 301-1A and 301-2A, [0224] ring A.sub.301 to ring A.sub.304 may each independently be a C.sub.3-C.sub.60 carbocyclic group that is unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group that is unsubstituted or substituted with at least one R.sub.10a, [0225] X.sub.301 may be O, S, N-[(L.sub.304).sub.xb4-R.sub.304a], C(R.sub.304a)(R.sub.304b), or Si(R.sub.304a)(R.sub.304b), [0226] X.sub.302 may be a single bond, O, S, N-[(L.sub.305).sub.xb5-R.sub.305a], C(R.sub.305a)(R.sub.305b), or Si(R.sub.305a)(R.sub.305b), [0227] X.sub.303 may be a single bond, O, S, N-[(L.sub.306).sub.xb6-R.sub.306a], C(R.sub.306a)(R.sub.306b), or Si(R.sub.306a)(R.sub.306b), [0228] xb22 and xb23 may each independently be an integer from 0 to 10, [0229] L.sub.301 to L.sub.307 may each independently be a C.sub.3-C.sub.60 carbocyclic group that is unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group that is unsubstituted or substituted with at least one R.sub.10a, [0230] xb1 to xb7 may each independently be an integer from 0 to 5, [0231] R.sub.301 to R.sub.303, R.sub.304a to R.sub.306a, R.sub.304b to R.sub.306b, and R.sub.311 to R.sub.314 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, 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 [0232] Q.sub.301 to Q.sub.303 may each independently be the same as described in connection with Q.sub.1.

[0233] In an embodiment, the first host may be one of Compounds HTH1 to HTH57, but embodiments are not limited thereto:

##STR00019## ##STR00020## ##STR00021## ##STR00022## ##STR00023## ##STR00024## ##STR00025## ##STR00026## ##STR00027## ##STR00028## ##STR00029## ##STR00030##

[0234] In an embodiment, the second host may be represented by Formula 302:

##STR00031##

[0235] In Formula 302, [0236] X.sub.321 may be C(R.sub.321) or N, X.sub.322 may be C(R.sub.322) or N, [0237] X.sub.323 may be C(R.sub.323) or N, at least one of X.sub.321 to X.sub.323 may each be N, [0238] L.sub.324 to L.sub.326 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, a C.sub.1-C.sub.60 heterocyclic group unsubstituted or substituted with at least one R.sub.10a, *C(Q.sub.321)(Q.sub.322)-*, *Si(Q.sub.321)(Q.sub.322)-**, *B(Q.sub.321)-*, or *N(Q.sub.321)-*, n324 to n326 may each independently be an integer from 1 to 5, [0239] R.sub.321 to R.sub.326 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, Si(Q.sub.323)(Q.sub.324)(Q.sub.325), N(Q.sub.323)(Q.sub.324), B(Q.sub.323)(Q.sub.324), C(O)(Q.sub.323), S(O).sub.2 (Q.sub.323), or P(O)(Q.sub.323)(Q.sub.324), [0240] two or more neighboring groups among Q.sub.321 to Q.sub.325 and R.sub.321 to R.sub.326 may optionally be bonded to each other to form a C.sub.5-C.sub.30 carbocyclic group unsubstituted or substituted with at least one R.sub.10a or a C.sub.2-C.sub.30 heterocyclic group unsubstituted or substituted with at least one R.sub.10a, * and * each indicate a binding site to a neighboring atom, [0241] R.sub.10a may be the same as described herein, and [0242] Q.sub.321 to Q.sub.325 may each independently be the same as described in connection with Q.sub.1.

[0243] In an embodiment, the second host may be one of Compounds ETH1 to ETH87, but embodiments are not limited thereto:

##STR00032## ##STR00033## ##STR00034## ##STR00035## ##STR00036## ##STR00037## ##STR00038## ##STR00039## ##STR00040## ##STR00041## ##STR00042## ##STR00043## ##STR00044## ##STR00045## ##STR00046## ##STR00047## ##STR00048## ##STR00049## ##STR00050##

[0244] In an embodiment, the sensitizer may be represented by Formula 401A:

##STR00051##

[0245] In Formulae 401A and 402A to 402D, [0246] M.sub.401 may be a first-row transition metal of the Periodic Table of Elements, a second-row transition metal of the Periodic Table of Elements, or a third-row transition metal of the Periodic Table of Elements, [0247] L.sub.401 may be a ligand represented by one of Formulae 402A to 402D, [0248] L.sub.402 may be a monodentate ligand, a bidentate ligand, or a tridentate ligand, [0249] xc1 may be 1 or 2, [0250] xc2 may be an integer from 0 to 4, [0251] A.sub.401 to A.sub.404 may each independently be a C.sub.5-C.sub.30 carbocyclic group or a C.sub.1-C.sub.30 heterocyclic group, [0252] T.sub.401 to T.sub.404 may each independently be a single bond, a double bond, *-O** *S*, *C(O)-*, *S(O)-*, *C(R.sub.405)(R.sub.406)-*, *C(R.sub.405)C(R.sub.406)-*, *C(R.sub.405)**, *Si(R.sub.405)(R.sub.406)-*, *B(R.sub.405)-*, *N(R.sub.405)-*, or *P(R.sub.405)-*, [0253] k401 to k404 may each independently be 1, 2, or 3, [0254] Y.sub.401 to Y.sub.404 may each independently be a single bond (for example, a covalent bond or a coordinate bond), *-O**, *S*, *C(R.sub.407)(R.sub.408)-*, *Si(R.sub.407)(R.sub.408)-*, *B(R.sub.407)-*, *N(R.sub.407)-*, or *P(R.sub.407)-*, [0255] *.sub.1, *.sub.2, *.sub.3, and *.sub.4 in Formulae 402A to 402D each indicate a binding site to M.sub.401 in Formula 401A, [0256] R.sub.401 to R.sub.408 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), [0257] R.sub.401 to R.sub.408 may optionally be bonded to each other to form a C.sub.5-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, [0258] b401 to b404 may each independently be an integer from 0 to 10, [0259] and * each indicate a binding site to a neighboring atom, and [0260] Q.sub.1 to Q.sub.3 and R.sub.10a may each be the same as described herein.

[0261] In an embodiment, the compound represented by Formula 401A may be a carbene complex.

[0262] The term carbene complex as used herein may be a complex which includes metal and a ligand bonded to the metal, wherein at least one bond between the metal and the ligand is a bond between the metal and a carbon atom of a carbene moiety.

[0263] In an embodiment, the sensitizer may include the compound represented by Formula 401A.

[0264] In an embodiment, the sensitizer may be one of Compounds PD1 to PD41, but embodiments are not limited thereto:

##STR00052## ##STR00053## ##STR00054## ##STR00055## ##STR00056## ##STR00057## ##STR00058## ##STR00059## ##STR00060## ##STR00061##

[0265] In an embodiment, R.sub.301 to R.sub.303, R.sub.304a to R.sub.306a, R.sub.304b to R.sub.306b, and R.sub.311 to R.sub.314 in Formulae 301-1A and 301-2A, R.sub.321 to R.sub.326 in Formula 302, and R.sub.401 to R.sub.408 in Formulae 401A and 402A to 402D may each independently be: [0266] hydrogen, deuterium, F, Cl, Br,-I, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazine group, a hydrazone group, a C.sub.1-C.sub.20 alkyl group, or a C.sub.1-C.sub.20 alkoxy group; [0267] 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, an amidino group, a hydrazine group, a hydrazone 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; [0268] 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 tetrahydronaphthyl 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 benzoisoquinolinyl group, a phthalazinyl group, a naphthyridinyl group, a quinoxalinyl group, a benzoquinoxalinyl group, a quinazolinyl group, a cinnolinyl group, a carbazolyl group, a phenanthridinyl group, an acridinyl group, a phenanthrolinyl group, a phenazinyl group, a benzoimidazolyl group, a benzofuranyl group, a benzothiophenyl group, a benzoisothiazolyl group, a benzoxazolyl group, an isobenzoxazolyl group, a triazolyl group, a tetrazolyl group, an oxadiazolyl group, a triazinyl group, a thiadiazolyl 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, or an azadibenzosilolyl 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, an amidino group, a hydrazine group, a hydrazone 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 tetrahydronaphthyl 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 benzoisoquinolinyl group, a phthalazinyl group, a naphthyridinyl group, a quinoxalinyl group, a benzoquinoxalinyl group, a quinazolinyl group, a cinnolinyl group, a carbazolyl group, a phenanthridinyl group, an acridinyl group, a phenanthrolinyl group, a phenazinyl group, a benzoimidazolyl group, a benzofuranyl group, a benzothiophenyl group, a benzoisothiazolyl group, a benzoxazolyl group, an isobenzoxazolyl group, a triazolyl group, a tetrazolyl group, an oxadiazolyl group, a triazinyl group, a thiadiazolyl 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, Si(Q.sub.31)(Q.sub.32)(Q.sub.33), 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 [0269] 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 [0270] Q.sub.1 to Q.sub.3 and Q.sub.31 to Q.sub.33 may each be the same as described herein.

[0271] In an embodiment, R.sub.301 to R.sub.303, R.sub.304a to R.sub.306a, R.sub.304b to R.sub.306b, and R.sub.311 to R.sub.314 in Formulae 301-1A and 301-2A, R.sub.321 to R.sub.326 in Formula 302, and R.sub.401 to R.sub.408 in Formulae 401A and 402A to 402D may each independently be: [0272] hydrogen, deuterium, F, Cl, Br,-I, CD.sub.3, CD.sub.2H, CDH.sub.2, CF.sub.3, CF.sub.2H, CFH.sub.2, 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, or a C.sub.1-C.sub.60 alkoxy group; [0273] a group represented by one of Formulae 9-1 to 9-61 or a group represented by one of Formulae 10-1 to 10-348; or [0274] 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):

##STR00062## ##STR00063## ##STR00064## ##STR00065## ##STR00066## ##STR00067## ##STR00068## ##STR00069## ##STR00070## ##STR00071## ##STR00072## ##STR00073## ##STR00074## ##STR00075## ##STR00076## ##STR00077## ##STR00078## ##STR00079## ##STR00080## ##STR00081## ##STR00082## ##STR00083## ##STR00084## ##STR00085## ##STR00086## ##STR00087## ##STR00088## ##STR00089## ##STR00090## ##STR00091## ##STR00092## ##STR00093## ##STR00094## ##STR00095## ##STR00096##

##STR00097## ##STR00098## ##STR00099## ##STR00100## ##STR00101## ##STR00102## ##STR00103## ##STR00104## ##STR00105## ##STR00106## ##STR00107## ##STR00108## ##STR00109## ##STR00110## ##STR00111## ##STR00112## ##STR00113## ##STR00114## ##STR00115##

[0275] In Formulae 9-1 to 9-61 and 10-1 to 10-348, * indicates a binding site to a neighboring atom, Ph represents a phenyl group, and TMS represents a trimethylsilyl group, D represents a deuterium atom, and [0276] Q.sub.1 to Q.sub.3 may each be the same as described herein.

[0277] In an embodiment, the electron transport region of the light-emitting device may include a hole blocking layer, and the hole blocking layer may include a phosphine oxide-containing compound, a silicon-containing compound, or any combination thereof. In an embodiment, the hole blocking layer may contact (e.g., directly contact) the emission layer.

[0278] In an embodiment, the light-emitting device may include a capping layer outside the first electrode or outside the second electrode.

[0279] For example, the light-emitting device may further include at least one of a first capping layer outside the first electrode and a second capping layer outside the second electrode, wherein at least one of the first capping layer and the second capping layer may include at least one of the first compound to the fourth compound. The first capping layer and/or the second capping layer may each be the same as described herein.

[0280] In an embodiment, the light-emitting device may further include: [0281] a first capping layer outside the first electrode and including at least one of the first compound to the fourth compound; [0282] a second capping layer outside the second electrode and including at least one of the first compound to the fourth compound; or the first capping layer and the second capping layer.

[0283] In the specification, the expression (interlayer and/or capping layer) includes one of the compounds among the first compound to the fourth compound as used herein may be understood as (interlayer and/or capping layer) may include one kind of compound among one of the first compound to the fourth compound or two different kinds of compounds among one of the first compounds to the fourth compounds.

[0284] In an embodiment, the interlayer and/or the capping layer may include only Compound DA-01 as one of the compounds among the first to fourth compounds. For example, Compound DA-01 may be present in the emission layer of the light-emitting device. For another example, the interlayer may include Compound DA-01 and Compound DA-02, as one of the compounds among the first compound to the fourth compound. For yet another example, Compound DA-01 and Compound DA-02 may be present in a same layer (for example, all of Compound DA-01 and Compound DA-02 may be present in the emission layer), or may be present in different layers (for example, Compound DA-01 may be present in the emission layer, and Compound DA-02 may be present in the electron transport region).

[0285] In the specification, the term interlayer may be a single layer and/or all layers between a first electrode and a second electrode of a light-emitting device.

[0286] According to embodiments, an electronic apparatus may include the light-emitting device. The electronic apparatus may further include a thin-film transistor. For example, the electronic apparatus may further include a thin-film transistor including a source electrode and a drain electrode, wherein the 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 touch screen layer, a polarizing layer, or any combination thereof. Further details on the electronic apparatus may be the same as described herein.

[0287] According to embodiments, an electronic equipment may include the electronic apparatus, and the electronic equipment may be a flat panel display, a curved display, a computer monitor, a medical monitor, a television, a billboard, an indoor light, an outdoor light, a signal light, a head-up display, a fully transparent display, a partially transparent display, a flexible display, a rollable display, a foldable display, a stretchable display, a laser printer, a telephone, a mobile phone, a tablet, a phablet, a personal digital assistant (PDA), a wearable device, a laptop computer, a digital camera, a camcorder, a viewfinder, a micro display, a three-dimensional (3D) display, a virtual reality display, an augmented reality display, a vehicle, a video wall including multiple displays tiled together, a theater screen, a stadium screen, a phototherapy device, or a signboard.

[Description of FIG. 1]

[0288] FIG. 1 is a schematic cross-sectional view of a light-emitting device 10 according to an embodiment. The light-emitting device 10 includes a first electrode 110, an interlayer 130, and a second electrode 150.

[0289] Hereinafter, a structure of the light-emitting device 10 according to an embodiment and a method of manufacturing the light-emitting device 10 are described with reference to FIG. 1.

[First Electrode 110]

[0290] In FIG. 1, a substrate may be further included under the first electrode 110 or on the second electrode 150. In an embodiment, the substrate may be a glass substrate or a plastic substrate. In an embodiment, the substrate may be a flexible substrate and may include plastics with excellent heat resistance and durability, such as polyimide, polyethylene terephthalate (PET), polycarbonate, polyethylene naphthalate, polyarylate (PAR), polyetherimide, or any combination thereof.

[0291] The first electrode 110 may be formed by, for example, depositing or sputtering a material for forming the first electrode 110 on the substrate. When the first electrode 110 is an anode, a material for forming the first electrode 110 may be a high-work function material that facilitates injection of holes.

[0292] The first electrode 110 may be a reflective electrode, a semi-transmissive electrode, or a transmissive electrode. When the first electrode 110 is a transmissive electrode, a material for forming the first electrode 110 may include indium tin oxide (ITO), indium zinc oxide (IZO), tin oxide (SnO.sub.2), zinc oxide (ZnO), or any combination thereof. In an embodiment, when the first electrode 110 is a semi-transmissive electrode or a reflective electrode, a material for forming the first electrode 110 may include magnesium (Mg), silver (Ag), aluminum (AI), aluminum-lithium (AlLi), calcium (Ca), magnesium-indium (Mg-In), magnesium-silver (MgAg), or any combination thereof.

[0293] The first electrode 110 may have a structure consisting of a single layer or a structure including multiple layers. In an embodiment, the first electrode 110 may have a three-layer structure of ITO/Ag/ITO.

[Interlayer 130]

[0294] The interlayer 130 may be disposed above the first electrode 110. The interlayer 130 may include the emission layer.

[0295] 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.

[0296] The interlayer 130 may further include, in addition to various organic materials, a metal-containing compound such as an organometallic compound, an inorganic material such as quantum dots, or the like.

[0297] In an embodiment, the interlayer 130 may include, two or more emitting units stacked between the first electrode 110 and the second electrode 150, and at least one charge generation layer which may each be between adjacent units among the two or more emitting units. When the interlayer 130 includes the two or more emitting units and the at least one charge generation layer as described above, the light-emitting device 10 may be a tandem light-emitting device. [Hole transport region in interlayer 130]

[0298] 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 structure including multiple layers including different materials.

[0299] The hole transport region may include a hole injection layer, a hole transport layer, an emission auxiliary layer, an electron blocking layer, or any combination thereof.

[0300] In an embodiment, the hole transport region may have a multilayer structure including 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 the layers of each structure may be stacked from the first electrode 110 in its respective stated order, but the structure of the hole transport region is not limited thereto.

[0301] The hole transport region may include a compound represented by Formula 201, a compound represented by Formula 202, or any combination thereof:

##STR00116## [0302] In Formulae 201 and 202, [0303] L.sub.201 to L.sub.204 may each independently be a C.sub.3-C.sub.60 carbocyclic group that is unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group that is unsubstituted or substituted with at least one R.sub.10a, [0304] L.sub.205 may be *-O**, *S*, *N(Q.sub.201)-*, a C.sub.1-C.sub.20 alkylene group that is unsubstituted or substituted with at least one R.sub.10a, a C.sub.2-C.sub.20 alkenylene group that is unsubstituted or substituted with at least one R.sub.10a, a C.sub.3-C.sub.60 carbocyclic group that is unsubstituted or substituted with at least one R.sub.10a, or a C.sub.1-C.sub.60 heterocyclic group that is unsubstituted or substituted with at least one R.sub.10a, [0305] xa1 to xa4 may each independently be an integer from 0 to 5, [0306] xa5 may be an integer from 1 to 10, [0307] R.sub.201 to R.sub.204 and Q.sub.201 may each independently be a C.sub.3-C.sub.60 carbocyclic group that is unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group that is unsubstituted or substituted with at least one R.sub.10a, [0308] R.sub.201 and R.sub.202 may optionally be linked to each other via a single bond, a C.sub.1-C.sub.5 alkylene group that is unsubstituted or substituted with at least one R.sub.10a, or a C.sub.2-C.sub.5 alkenylene group that is unsubstituted or substituted with at least one R.sub.10a to form a C.sub.8-C.sub.60 polycyclic group (for example, a carbazole group) that is unsubstituted or substituted with at least one R.sub.10a (for example, Compound HT16), [0309] R.sub.203 and R.sub.204 may optionally be linked to each other via a single bond, a C.sub.1-C.sub.5 alkylene group that is unsubstituted or substituted with at least one R.sub.10a, or a C.sub.2-C.sub.5 alkenylene group that is unsubstituted or substituted with at least one R.sub.10a to form a C.sub.8-C.sub.60 polycyclic group that is unsubstituted or substituted with at least one R.sub.10a, and [0310] na1 may be an integer from 1 to 4.

[0311] In an embodiment, the compound represented by Formula 201 and the compound represented by Formula 202 may each independently include at least one of groups represented by Formulae CY201 to CY217:

##STR00117## ##STR00118##

[0312] 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 CY201 to ring CY204 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 as described herein.

[0313] In an embodiment, in Formulae CY201 to CY217, ring CY201 to ring CY204 may each independently be a benzene group, a naphthalene group, a phenanthrene group, or an anthracene group.

[0314] In an embodiment, the compound represented by Formula 201 and the compound represented by Formula 202 may each independently include at least one of groups represented by Formulae CY201 to CY203.

[0315] In an embodiment, the compound represented by 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.

[0316] In an embodiment, in Formula 201, xa1 may be 1, R.sub.201 may be a group represented by one of Formulae CY201 to CY203, xa2 may be 0, and R.sub.202 may be a group represented by one of Formulae CY204 to CY207.

[0317] In an embodiment, the compound represented by Formula 201 and the compound represented by Formula 202 may each not include groups represented by Formulae CY201 to CY203.

[0318] In an embodiment, the compound represented by Formula 201 and the compound represented by Formula 202 may each not include groups represented by Formulae CY201 to CY203 and may each independently include at least one of groups represented by Formulae CY204 to CY217.

[0319] In an embodiment, the compound represented by Formula 201 and the compound represented by Formula 202 may each not include groups represented by Formulae CY201 to CY217.

[0320] In an embodiment, the hole transport region may include one of Compounds HT1 to HT46, m-MTDATA, TDATA, 2-TNATA, NPB(NPD), 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/camphor sulfonic acid (PANI/CSA), polyaniline/poly(4-styrenesulfonate) (PANI/PSS), or any combination thereof:

##STR00119## ##STR00120## ##STR00121## ##STR00122## ##STR00123## ##STR00124## ##STR00125## ##STR00126## ##STR00127## ##STR00128## ##STR00129## ##STR00130## ##STR00131## ##STR00132## ##STR00133## ##STR00134## ##STR00135## ##STR00136##

[0321] A thickness of the hole transport region may be in a range of about 50 to about 10,000 . For example, the thickness of the hole transport region may be in a range of about 100 to about 4,000 . 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 to about 9,000 , and a thickness of the hole transport layer may be about 50 to about 2,000 . For example, the thickness of the hole injection layer may be in a range of about 100 to about 1,000 . For example, the thickness of the hole transport layer may be in a range of about 100 to about 1,500 . When the thicknesses of the hole transport region, the hole injection layer, and the hole transport layer are within the ranges described above, satisfactory hole-transporting characteristics may be obtained without a substantial increase in driving voltage.

[0322] The emission auxiliary layer may increase light-emission efficiency by compensating for an optical resonance distance according to the wavelength of light emitted by the emission layer, and the electron blocking layer may block the leakage of electrons from the emission layer to the hole transport region. Materials that may be included in the hole transport region may be included in the emission auxiliary layer and the electron blocking layer.

[p-Dopant]

[0323] The hole transport region may further include, in addition to these materials, a charge-generation material for the improvement of conductive properties. The charge-generation material may be uniformly or non-uniformly dispersed in the hole transport region (for example, in the form of a single layer consisting of a charge-generation material).

[0324] The charge-generation material may be, for example, a p-dopant.

[0325] For example, a lowest unoccupied molecular orbital (LUMO) energy of the p-dopant may be less than or equal to about 3.5 eV.

[0326] In an embodiment, the p-dopant may include a quinone derivative, a cyano group-containing compound, a compound including an element EL1 and an element EL2, or any combination thereof.

[0327] Examples of a quinone derivative may include TCNQ and F4-TCNQ.

[0328] Examples of a cyano group-containing compound may include HAT-CN and a compound represented by Formula 221.

##STR00137##

[0329] In Formula 221, [0330] R.sub.221 to R.sub.223 may each independently be a C.sub.3-C.sub.60 carbocyclic group that is unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group that is unsubstituted or substituted with at least one R.sub.10a, and [0331] at least one of R.sub.221 to R.sub.223 may each independently be a C.sub.5-C.sub.60 carbocyclic group or a C.sub.1-C.sub.60 heterocyclic group, each 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.

[0332] In the compound including the element EL1 and the element EL2, the element EL1 may be a metal, a metalloid, or any combination thereof, and the element EL2 may be a non-metal, a metalloid, or any combination thereof.

[0333] Examples of a metal may include an alkali metal (for example, lithium (Li), sodium (Na), potassium (K), rubidium (Rb), cesium (Cs), etc.); an alkaline earth metal (for example, beryllium (Be), magnesium (Mg), calcium (Ca), strontium (Sr), barium (Ba), etc.); a transition metal (for example, 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), etc.); a post-transition metal (for example, zinc (Zn), indium (In), tin (Sn), etc.); and a lanthanide metal (for example, 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), etc.).

[0334] Examples of a metalloid may include silicon (Si), antimony (Sb), and tellurium (Te).

[0335] Examples of a non-metal may include oxygen (O) and halogen (for example, F, C.sub.1, Br, I, etc.).

[0336] Examples of a compound including the element EL1 and the element EL2 may include a metal oxide, a metal halide (for example, a metal fluoride, a metal chloride, a metal bromide, a metal iodide, etc.), a metalloid halide (for example, a metalloid fluoride, a metalloid chloride, a metalloid bromide, a metalloid iodide, etc.), a metal telluride, or any combination thereof.

[0337] Examples of a metal oxide may include a tungsten oxide (for example, WO, W.sub.2O.sub.3, WO.sub.2, WO.sub.3, W.sub.2O.sub.5, etc.), a vanadium oxide (for example, VO, V.sub.2O.sub.3, VO.sub.2, V.sub.2O.sub.5, etc.), a molybdenum oxide (MoO, Mo.sub.2O.sub.3, MoO.sub.2, MoO.sub.3, Mo.sub.2O.sub.5, etc.), and a rhenium oxide (for example, ReO.sub.3, etc.).

[0338] Examples of a metal halide may include an alkali metal halide, an alkaline earth metal halide, a transition metal halide, a post-transition metal halide, and a lanthanide metal halide.

[0339] Examples of an alkali metal halide may include LiF, NaF, KF, RbF, CsF, LiCI, NaCl, KCl, RbCl, CsCl, LiBr, NaBr, KBr, RbBr, CsBr, LiI, Nal, KI, RbI, and CsI.

[0340] Examples of an 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, Bel.sub.2, Mgl.sub.2, Cal.sub.2, Srl.sub.2, and Bal.sub.2.

[0341] Examples of a transition metal halide may include a titanium halide (for example, TiF.sub.4, TiCl.sub.4, TiBr.sub.4, Til.sub.4, etc.), a zirconium halide (for example, ZrF.sub.4, ZrCl.sub.4, ZrBr.sub.4, Zrl.sub.4, etc.), a hafnium halide (for example, HfF.sub.4, HfCI.sub.4, HfBr.sub.4, Hfl.sub.4, etc.), a vanadium halide (for example, VF.sub.3, VCl.sub.3, VBr.sub.3, VI.sub.3, etc.), a niobium halide (for example, NbF.sub.3, NbCl.sub.3, NbBr.sub.3, NbI.sub.3, etc.), a tantalum halide (for example, TaF.sub.3, TaCl.sub.3, TaBr.sub.3, TaI.sub.3, etc.), a chromium halide (for example, CrF.sub.3, CrCl.sub.3, CrBr.sub.3, CrI.sub.3, etc.), a molybdenum halide (for example, MoF.sub.3, MoCl.sub.3, MoBr.sub.3, MoIs, etc.), a tungsten halide (for example, WF.sub.3, WCI.sub.3, WBr.sub.3, Wls, etc.), a manganese halide (for example, MnF.sub.2, MnCl.sub.2, MnBr.sub.2, Mnl.sub.2, etc.), a technetium halide (for example, TcF.sub.2, TcCl.sub.2, TcBr.sub.2, Tcl.sub.2, etc.), a rhenium halide (for example, ReF.sub.2, ReCl.sub.2, ReBr.sub.2, Rel.sub.2, etc.), an iron halide (for example, FeF.sub.2, FeCl.sub.2, FeBr.sub.2, Fel.sub.2, etc.), a ruthenium halide (for example, RuF.sub.2, RuCl.sub.2, RuBr.sub.2, Rul.sub.2, etc.), an osmium halide (for example, OsF.sub.2, OsCl.sub.2, OsBr.sub.2, Osl.sub.2, etc.), a cobalt halide (for example, CoF.sub.2, CoCl.sub.2, CoBr.sub.2, Col.sub.2, etc.), a rhodium halide (for example, RhF.sub.2, RhCl.sub.2, RhBr.sub.2, Rhl.sub.2, etc.), an iridium halide (for example, IrF.sub.2, IrCl.sub.2, IrBr.sub.2, Irl.sub.2, etc.), a nickel halide (for example, NiF.sub.2, NiCl.sub.2, NiBr.sub.2, Nil.sub.2, etc.), a palladium halide (for example, PdF.sub.2, PdCl.sub.2, PdBr.sub.2, Pdl.sub.2, etc.), a platinum halide (for example, PtF.sub.2, PtCl.sub.2, PtBr.sub.2, Ptl.sub.2, etc.), a copper halide (for example, CuF, CuCl, CuBr, Cul, etc.), a silver halide (for example, AgF, AgCl, AgBr, AgI, etc.), and a gold halide (for example, AuF, AuCl, AuBr, AuI, etc.).

[0342] Examples of a post-transition metal halide may include a zinc halide (for example, ZnF.sub.2, ZnCl.sub.2, ZnBr.sub.2, ZnI.sub.2, etc.), an indium halide (for example, Inl.sub.3, etc.), and a tin halide (for example, Snl.sub.2, etc.).

[0343] Examples of a 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, Ybl.sub.2, YbI.sub.3, and SmI.sub.3.

[0344] Examples of a metalloid halide may include an antimony halide (for example, SbCl.sub.5, etc.).

[0345] Examples of a metal telluride may include an alkali metal telluride (for example, LizTe, NazTe, K.sub.2Te, Rb.sub.2Te, Cs.sub.2Te, etc.), an alkaline earth metal telluride (for example, BeTe, MgTe, CaTe, SrTe, BaTe, etc.), a transition metal telluride (for example, TiTe.sub.2, ZrTe.sub.2, HfTe.sub.2, V.sub.2Te.sub.3, Nb.sub.2Te.sub.3, Ta.sub.2Tes, Cr.sub.2Te.sub.3, Mo.sub.2Te.sub.3, W.sub.2Te.sub.3, MnTe, ToTe, ReTe, FeTe, RuTe, OsTe, CoTe, RhTe, IrTe, NiTe, PdTe, PtTe, CuzTe, CuTe, Ag.sub.2Te, AgTe, Au.sub.2Te, etc.), a post-transition metal telluride (for example, ZnTe, etc.), and a lanthanide metal telluride (for example, LaTe, CeTe, PrTe, NdTe, PmTe, EuTe, GdTe, TbTe, DyTe, HoTe, ErTe, TmTe, YbTe, LuTe, etc.).

[Emission Layer in Interlayer 130]

[0346] 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 an embodiment, the emission layer may have a stacked structure of two or more layers of a red emission layer, a green emission layer, and a blue emission layer, in which the two or more layers may contact each other or may be separated from each other, to emit white light. In embodiments, the emission layer may include two or more materials of a red light-emitting material, a green light-emitting material, and a blue light-emitting material, in which the two or more materials are mixed with each other in a single layer, to emit white light.

[0347] The emission layer may include a host and a dopant. The dopant may include a phosphorescent dopant, a fluorescent dopant, or any combination thereof.

[0348] An amount of the dopant in the emission layer may be from about 0.01 part by weight to about 15 parts by weight based on 100 parts by weight of the host.

[0349] In an embodiment, the emission layer may include a quantum dot.

[0350] In an embodiment, the emission layer may include a delayed fluorescence material. The delayed fluorescence material may serve as a host or as a dopant in the emission layer.

[0351] A thickness of the emission layer may be in a range of about 100 to about 1,000 . For example, the thickness of the emission layer may be in a range of about 200 to about 600 . When the thickness of the emission layer is within any of the ranges described above, excellent luminescence characteristics may be obtained without a substantial increase in driving voltage.

[Host]

[0352] The host may further include a compound represented by Formula 301:

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

[0353] In Formula 301, [0354] Ar.sub.301 and L.sub.301 may each independently be a C.sub.5-C.sub.60 carbocyclic group that is unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group that is unsubstituted or substituted with at least one R.sub.10a, [0355] xb11 may be 1, 2, or 3, [0356] xb1 may be an integer from 0 to 5, [0357] 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 that is unsubstituted or substituted with at least one R.sub.10a, a C.sub.2-C.sub.60 alkenyl group that is unsubstituted or substituted with at least one R.sub.10a, a C.sub.2-C.sub.60 alkynyl group that is unsubstituted or substituted with at least one R.sub.10a, a C.sub.1-C.sub.60 alkoxy group that is unsubstituted or substituted with at least one R.sub.10a, a C.sub.3-C.sub.60 carbocyclic group that is unsubstituted or substituted with at least one R.sub.10a, a C.sub.1-C.sub.60 heterocyclic group that is 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), [0358] xb21 may be an integer from 1 to 5, and [0359] Q.sub.301 to Q.sub.303 may each independently be the same as described in connection with Q.sub.1.

[0360] In an embodiment, in Formula 301, when xb11 is 2 or more, two or more of Ar.sub.301 may be linked to each other via a single bond.

[0361] In an embodiment, the host may include a compound represented by Formula 301-1, a compound represented by Formula 301-2, or any combination thereof:

##STR00138## [0362] In Formulae 301-1 and 301-2, [0363] ring A.sub.301 to ring A.sub.304 may each independently be a C.sub.3-C.sub.60 carbocyclic group that is unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group that is unsubstituted or substituted with at least one R.sub.10a, [0364] 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), [0365] xb22 and xb23 may each independently be 0, 1, or 2, [0366] L.sub.301, xb1, and R.sub.301 may each independently be the same as described herein, [0367] L.sub.302 to L.sub.304 may each independently be the same as described in connection with L.sub.301, [0368] xb2 to xb4 may each independently be the same as described in connection with xb1, and [0369] R.sub.302 to R.sub.305 and R.sub.311 to R.sub.314 may each independently be the same as described in connection with R.sub.301.

[0370] In an embodiment, the host may include an alkali earth metal complex, a post-transition metal complex, or any combination thereof. In an embodiment, the host may include a Be complex (for example, Compound H.sub.55), an Mg complex, a Zn complex, or any combination thereof.

[0371] In an embodiment, the host may include: one of Compounds H.sub.1 to H128; 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:

##STR00139## ##STR00140## ##STR00141## ##STR00142## ##STR00143## ##STR00144## ##STR00145## ##STR00146## ##STR00147## ##STR00148## ##STR00149## ##STR00150## ##STR00151## ##STR00152## ##STR00153## ##STR00154## ##STR00155## ##STR00156## ##STR00157## ##STR00158## ##STR00159## ##STR00160##

##STR00161## ##STR00162## ##STR00163## ##STR00164## ##STR00165## ##STR00166## ##STR00167## ##STR00168##

[Phosphorescent Dopant]

[0372] The phosphorescent dopant may include at least one transition metal as a central metal.

[0373] 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.

[0374] The phosphorescent dopant may be electrically neutral.

[0375] In an embodiment, the phosphorescent dopant may include an organometallic compound represented by Formula 401:

##STR00169## [0376] In Formulae 401 and 402, [0377] M may be a transition metal (for example, 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)), [0378] L.sub.401 may be a ligand represented by Formula 402, and xc1 may be 1, 2, or 3, wherein when xc1 is 2 or more, two or more of L.sub.401 may be identical to or different from each other, [0379] L.sub.402 may be an organic ligand, and xc2 may be 0, 1, 2, 3, or 4, wherein, when xc2 is 2 or more, two or more of L.sub.402 may be identical to or different from each other, [0380] X.sub.401 and X.sub.402 may each independently be nitrogen or carbon, [0381] 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, [0382] T.sub.401 may be a single bond, *-O**, *S*, *C(O)-*, *N(Q.sub.411)-*, *C(Q.sub.411)(Q.sub.412)-*, *C(Q.sub.411)C(Q.sub.412)-*, *C(Q.sub.411)**, or *C*, [0383] X.sub.403 and X.sub.404 may each independently be a chemical bond (for example, 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), [0384] Q.sub.411 to Q.sub.414 may each independently be the same as described in connection with Q.sub.1, [0385] 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 that is unsubstituted or substituted with at least one R.sub.10a, a C.sub.1-C.sub.20 alkoxy group that is unsubstituted or substituted with at least one R.sub.10a, a C.sub.3-C.sub.60 carbocyclic group that is unsubstituted or substituted with at least one R.sub.10a, a C.sub.1-C.sub.60 heterocyclic group that is 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), [0386] Q.sub.401 to Q.sub.403 may each independently be the same as described in connection with Q.sub.1, [0387] xc11 and xc12 may each independently be an integer from 0 to 10, and [0388] * and * in Formula 402 each indicate a binding site to M in Formula 401.

[0389] In an embodiment, 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 each be nitrogen.

[0390] In an embodiment, in Formula 401, when xc1 is 2 or more, two ring A.sub.401 in two or more of L.sub.401 may be optionally linked to each other via T.sub.402, which is a linking group, or two ring A.sub.402 may be optionally linked to each other via T.sub.403, which is a linking group (see Compounds PD1 to PD4 and PD7). T.sub.402 and T.sub.403 may each independently be the same as described in connection with T.sub.401.

[0391] L.sub.402 in Formula 401 may be an organic ligand. In an embodiment, L.sub.402 may include a halogen group, a diketone group (for example, an acetylacetonate group), a carboxylic acid group (for example, a picolinate group), C(O), an isonitrile group, a-CN group, a phosphorus group (for example, a phosphine group, a phosphite group, etc.), or any combination thereof.

[0392] The phosphorescent dopant may include, for example, one of Compounds PD1 to PD39, or any combination thereof:

##STR00170## ##STR00171## ##STR00172## ##STR00173## ##STR00174## ##STR00175## ##STR00176## ##STR00177## ##STR00178## ##STR00179##

[Fluorescent Dopant]

[0393] The fluorescent dopant may include an amine group-containing compound, a styryl group-containing compound, or any combination thereof.

[0394] In an embodiment, the fluorescent dopant may include a compound represented by Formula 501:

##STR00180##

[0395] In Formula 501, [0396] 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 that is unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group that is unsubstituted or substituted with at least one R.sub.10a, [0397] xd1 to xd3 may each independently be 0, 1, 2, or 3, and [0398] xd4 may be 1, 2, 3, 4, 5, or 6.

[0399] In an embodiment, in Formula 501, Ar.sub.501 may be a condensed cyclic group (for example, an anthracene group, a chrysene group, a pyrene group, etc.) in which three or more monocyclic groups are condensed together.

[0400] In an embodiment, in Formula 501, xd4 may be 2.

[0401] In an embodiment, the fluorescent dopant may include: one of Compounds FD1 to FD37; DPVBi; DPAVBi; or any combination thereof:

##STR00181## ##STR00182## ##STR00183## ##STR00184## ##STR00185##

[Delayed Fluorescence Material]

[0402] The emission layer may include a delayed fluorescence material.

[0403] The delayed fluorescence material may be selected from compounds capable of emitting delayed fluorescence based on a delayed fluorescence emission mechanism.

[0404] The delayed fluorescence material included in the emission layer may serve as a host or as a dopant depending on the type of other materials included in the emission layer.

[0405] In an embodiment, a difference between a triplet energy level (eV) of the delayed fluorescence material and a singlet energy level (eV) of the delayed fluorescence material may be in a range of about 0 eV to about 0.5 eV. When the difference between the triplet energy level (eV) of the delayed fluorescence material and the singlet energy level (eV) of the delayed fluorescence material is satisfied within the range described above, up-conversion from the triplet state to the singlet state of the delayed fluorescence materials may effectively occur, and thus, the light-emitting device 10 may have improved luminescence efficiency.

[0406] In an embodiment, the delayed fluorescence material may include: a material including at least one electron donor (for example, a electron-rich C.sub.3-C.sub.60 cyclic group such as a carbazole group) and at least one electron acceptor (for example, a sulfoxide group, a cyano group, a Ir electron-deficient nitrogen-containing C.sub.1-C.sub.60 cyclic group, and the like), or a material including a C.sub.8-C.sub.60 polycyclic group including at least two cyclic groups that are condensed with each other while sharing boron (B).

[0407] In an embodiment, the delayed fluorescence material may include at least one of Compounds DF1 to DF14:

##STR00186## ##STR00187## ##STR00188## ##STR00189##

[Quantum Dot]

[0408] In an embodiment, the emission layer may include quantum dots.

[0409] In the specification, a quantum dot may be a crystal of a semiconductor compound, and may include any material capable of emitting light of various emission wavelengths according to a size of the crystal.

[0410] A diameter of the quantum dot may be, for example, in a range of about 1 nm to about 10 nm.

[0411] The quantum dot may be synthesized by a wet chemical process, a metal organic chemical vapor deposition process, a molecular beam epitaxy process, or any process similar thereto.

[0412] The wet chemical process is a method including mixing a precursor material with an organic solvent and growing quantum dot particle crystals. When the crystal grows, the organic solvent naturally serves as a dispersant coordinated on the surface of the quantum dot crystal and controls the growth of the crystal so that the growth of quantum dot particles can be controlled through a process which costs less, and may be more readily performed than vapor deposition methods, such as metal organic chemical vapor deposition (MOCVD) or molecular beam epitaxy (MBE).

[0413] 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 IIII-VI semiconductor compound; a Group IV-VI semiconductor compound; a Group IV element or compound; or any combination thereof.

[0414] Examples of a 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.

[0415] Examples of a Group III-V semiconductor compound may include: a binary compound, such as GaN, GaP, GaAs, GaSb, AlN, AlP, AIAs, AISb, InN, InP, InAs, or InSb; a ternary compound, such as GaNP, GaNAs, GaNSb, GaPAs, GaPSb, AlNP, AlNAs, AlNSb, AIPAs, AIPSb, InGaP, InNP, InAIP, InNAs, InNSb, InPAs, or InPSb; a quaternary compound, such as GaAINP, GaAINAs, GaAINSb, GaAIPAs, GaAIPSb, GalnNP, GalnNAs, GalnNSb, GalnPAs, GalnPSb, InAINP, InAINAs, InAINSb, InAIPAs, or InAIPSb; or any combination thereof. In an embodiment, a Group III-V semiconductor compound may further include a Group Il element. Examples of a Group III-V semiconductor compound further including the Group Il element may include InZnP, InGaZnP, and InAIZnP.

[0416] Examples of a Group III-VI semiconductor compound may include: a binary compound, such as GaS, GaSe, GazSes, GaTe, InS, InSe, In.sub.2S.sub.3, In.sub.2Se.sub.3, or InTe; a ternary compound, such as InGaSs or InGaSes; or any combination thereof.

[0417] Examples of a Group IIII-VI semiconductor compound may include: a ternary compound, such as AglnS, AglnS.sub.2, CulnS, CulnS.sub.2, CuGaO.sub.2, AgGaO.sub.2, or AgAlO.sub.2; or any combination thereof.

[0418] Examples of a 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.

[0419] Examples of a Group IV element or compound may include: a single element material, such as Si or Ge; a binary compound, such as SiC or SiGe; or any combination thereof.

[0420] Each element included in a multi-element compound, such as a binary compound, a ternary compound, or a quaternary compound, may be present at a uniform concentration or non-uniform concentration in a particle.

[0421] In an embodiment, the quantum dot may have a single structure in which the concentration of each element in the quantum dot is uniform, or the quantum dot may have a core-shell structure. In an embodiment, a material included in the core and a material included in the shell may be different from each other.

[0422] The shell of the quantum dot may serve as a protective layer that prevents chemical denaturation of the core to maintain semiconductor characteristics, and/or may serve as a charging layer that imparts electrophoretic characteristics to the quantum dot. The shell may be a single layer or a multilayer. An interface between the core and the shell may have a concentration gradient in which the concentration of a material that is present in the shell decreases toward the core.

[0423] Examples of a material forming the shell of the quantum dot may include a metal oxide, a metalloid oxide, or a non-metal oxide, a semiconductor compound, or any combination thereof. Examples of a metal oxide, a metalloid oxide, or a non-metal 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 a semiconductor compound may include: a Group II-VI semiconductor compound; a Group III-V semiconductor compound; a Group III-VI semiconductor compound; a Group IIII-VI semiconductor compound; a Group IV-VI semiconductor compound; or any combination thereof. Examples of the semiconductor compound may include CdS, CdSe, CdTe, ZnS, ZnSe, ZnTe, ZnSeS, ZnTeS, GaAs, GaP, GaSb, HgS, HgSe, HgTe, InAs, InP, InGaP, InSb, AlAs, AlP, AISb, or any combination thereof.

[0424] The quantum dot may have a full width at half maximum (FWHM) of an emission wavelength spectrum less than or equal to about 45 nm. For example, the quantum dot may have an FWHM of an emission wavelength spectrum less than or equal to about 40 nm. For example, the quantum dot may have an FWHM of an emission wavelength spectrum less than or equal to about 30 nm. When the FWHM of the quantum dot is within any of these ranges, the quantum dot may have improved color purity or improved color reproducibility. Light emitted through the quantum dot may be emitted in all directions, so that a wide viewing angle may be improved.

[0425] The quantum dot may be in the form of spherical particle, a pyramidal particle, a multi-arm particle, or a cubic particle, or the quantum dot may be in the form of nanoparticles, nanotubes, nanowires, nanofibers, or nanoplate particles.

[0426] Since the energy band gap may be adjusted by controlling the size of the quantum dot, light having various wavelength bands may be obtained from the quantum dot emission layer. Accordingly, by using quantum dots of different sizes, a light-emitting device that emits light of various wavelengths may be implemented. In an embodiment, the size of the quantum dot may be selected to emit red light, green light, and/or blue light. In an embodiment, the size of the quantum dot may be configured to emit white light by combination of light of various colors.

[Electron Transport Region in Interlayer 130]

[0427] 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 structure including multiple layers including different materials.

[0428] The electron transport region may include a buffer layer, a hole blocking layer, an electron control layer, an electron transport layer, an electron injection layer, or any combination thereof.

[0429] In an embodiment, 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 the layers of each structure may be stacked from the emission layer in its respective stated order, but the structure of the electron transport region is not limited thereto.

[0430] In an embodiment, the electron transport region (for example, 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 TT electron-deficient nitrogen-containing C.sub.1-C.sub.60 cyclic group.

[0431] In an embodiment, 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]

[0432] In Formula 601, [0433] Ar.sub.601 and L.sub.601 may each independently be a C.sub.3-C.sub.60 carbocyclic group that is unsubstituted or substituted with at least one R.sub.10a or a C.sub.1-C.sub.60 heterocyclic group that is unsubstituted or substituted with at least one R.sub.10a, [0434] xe11 may be 1, 2, or 3, [0435] xe1 may be 0, 1, 2, 3, 4, or 5, [0436] R.sub.601 may be a C.sub.3-C.sub.60 carbocyclic group that is unsubstituted or substituted with at least one R.sub.10a, a C.sub.1-C.sub.60 heterocyclic group that is 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), [0437] Q.sub.601 to Q.sub.603 may each independently be the same as described in connection with Q.sub.1, [0438] xe21 may be 1, 2, 3, 4, or 5, and [0439] at least one of Ar.sub.601, L.sub.601, and R.sub.601 may each independently be a IT electron-deficient nitrogen-containing C.sub.1-C.sub.60 cyclic group that is unsubstituted or substituted with at least one R.sub.10a.

[0440] In an embodiment, in Formula 601, when xe11 is 2 or more, two or more of Ar.sub.601 may be linked together via a single bond.

[0441] In an embodiment, in Formula 601, Ar.sub.601 may be a substituted or unsubstituted anthracene group.

[0442] In an embodiment, the electron transport region may include a compound represented by Formula 601-1:

##STR00190## [0443] In Formula 601-1, [0444] 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 each be N, [0445] L.sub.611 to L.sub.613 may each independently be the same as described in connection with L.sub.601, [0446] xe611 to xe613 may each independently be the same as described in connection with xe1, [0447] R.sub.611 to R.sub.613 may each independently be the same as described in connection with R.sub.601, and [0448] 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.5-C.sub.60 carbocyclic group that is unsubstituted or substituted with at least one R.sub.10a, or a C.sub.1-C.sub.60 heterocyclic group that is unsubstituted or substituted with at least one R.sub.10a.

[0449] In an embodiment, in Formulae 601 and 601-1, xe1 and xe611 to xe613 may each independently be 0, 1, or 2.

[0450] 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:

##STR00191## ##STR00192## ##STR00193## ##STR00194## ##STR00195## ##STR00196## ##STR00197## ##STR00198## ##STR00199## ##STR00200## ##STR00201## ##STR00202## ##STR00203## ##STR00204## ##STR00205##

[0451] A thickness of the electron transport region may be in a range of about 100 to about 5,000 . For example, the thickness of the electron transport region may be in a range of about 160 to about 4,000 . 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 to about 1,000 , and a thickness of the electron transport layer may be in a range of about 100 to about 1,000 . 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 to about 300 . For example, the thickness of the electron transport layer may be in a range of about 150 to about 500 . When the thickness of the buffer layer, the hole blocking layer, the electron control layer, the electron transport layer, and/or the electron transport region are within these ranges, satisfactory electron-transporting characteristics may be obtained without a substantial increase in driving voltage.

[0452] 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.

[0453] 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 Li ion, a Na ion, a K ion, a Rb ion, or a Cs ion; and a metal ion of the alkaline earth metal complex may be a Be ion, a Mg ion, a Ca ion, a Sr ion, or a Ba ion. A ligand coordinated with a metal ion of an alkali metal complex or an alkaline earth-metal complex may each independently include a hydroxyquinoline, a hydroxyisoquinoline, a hydroxybenzoquinoline, a hydroxyacridine, hydroxyphenanthridine, a hydroxyphenyloxazole, a hydroxyphenylthiazole, a hydroxyphenyloxadiazole, a hydroxyphenylthiadiazole, a hydroxyphenylpyridine, a hydroxyphenylbenzimidazole, a hydroxyphenylbenzothiazole, a bipyridine, a phenanthroline, a cyclopentadiene, or any combination thereof.

[0454] In an embodiment, the metal-containing material may include a Li complex. The Li complex may include, for example, Compound ET-D1 (LiQ) or Compound ET-D2:

##STR00206##

[0455] The electron transport region may include an electron injection layer that facilitates the injection of electrons from the second electrode 150. The electron injection layer may contact (e.g., directly contact) the second electrode 150.

[0456] 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 structure including multiple layers including different materials.

[0457] 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.

[0458] The alkali metal may include Li, Na, K, Rb, Cs, or any combination thereof. The alkaline earth metal may include Mg, Ca, Sr, Ba, or any combination thereof. The rare earth metal may include Sc, Y, Ce, Tb, Yb, Gd, or any combination thereof.

[0459] The alkali metal-containing compound, the alkaline earth metal-containing compound, and the rare earth metal-containing compound may include oxides, halides (for example, fluorides, chlorides, bromides, iodides, etc.), or tellurides of the alkali metal, the alkaline earth metal, and the rare earth metal, or any combination thereof.

[0460] The alkali metal-containing compound may include: an alkali metal oxide, such as Li.sub.2O, Cs.sub.2O, or K.sub.2O; an alkali metal halide, such as LiF, NaF, CsF, KF, LiI, Nal, CsI, or KI; or any combination thereof. The alkaline earth metal-containing compound may include an alkaline earth metal compound, such as BaO, SrO, CaO, Ba.sub.xSr.sub.1-xO (x is a real number satisfying 0<x<1), or BaxCa.sub.1-xO (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.203, 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 an embodiment, the rare earth metal-containing compound may include a lanthanide metal telluride. Examples of a lanthanide metal telluride may include LaTe, CeTe, PrTe, NdTe, PmTe, SmTe, EuTe, GdTe, TbTe, DyTe, HoTe, ErTe, TmTe, YbTe, LuTe, La.sub.2Tes, Ce.sub.2Tes, Pr.sub.2Te.sub.3, Nd.sub.2Te.sub.3, Pm.sub.2Tes, Sm.sub.2Tes, Eu.sub.2Tes, Gd.sub.2Tes, Tb.sub.2Tes, Dy.sub.2Tes, Ho.sub.2Tes, Er.sub.2Tes, Tm.sub.2Te.sub.3, Yb.sub.2Te.sub.3, and LuzTe.sub.3.

[0461] The alkali metal complex, the alkaline earth-metal complex, and the rare earth metal complex may include an alkali metal ion, an alkaline earth metal ion, or a rare earth metal ion; and a ligand bonded to the metal ion, for example, a hydroxyquinoline, a hydroxyisoquinoline, a hydroxybenzoquinoline, a hydroxyacridine, a hydroxyphenanthridine, a hydroxyphenyloxazole, a hydroxyphenylthiazole, a hydroxyphenyloxadiazole, a hydroxyphenylthiadiazole, a hydroxyphenylpyridine, a hydroxyphenyl benzimidazole, a hydroxyphenylbenzothiazole, a bipyridine, a phenanthroline, a cyclopentadiene, or any combination thereof.

[0462] 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 an embodiment, the electron injection layer may further include an organic material (for example, a compound represented by Formula 601).

[0463] In an embodiment, the electron injection layer may consist of an alkali metal-containing compound (for example, an alkali metal halide), or the electron injection layer may consist of an alkali metal-containing compound (for example, an alkali metal halide), and an alkali metal, an alkaline earth metal, a rare earth metal, or any combination thereof. In an embodiment, the electron injection layer may be a KI: Yb co-deposited layer, an RbI:Yb co-deposited layer, a LiF:Yb co-deposited layer, or the like.

[0464] 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 uniformly or non-uniformly dispersed in a matrix including the organic material.

[0465] A thickness of the electron injection layer may be in a range of about 1 to about 100 . For example, the thickness of the electron injection layer may be in a range of about 3 to about 90 . When the thickness of the electron injection layer is within any of the ranges as described above, satisfactory electron injection characteristics may be obtained without a substantial increase in driving voltage.

[Second Electrode 150]

[0466] The second electrode 150 may be arranged on the interlayer 130. The second electrode 150 may be a cathode, which is an electron injection electrode. When the second electrode 150 is a cathode, a material for forming the second electrode 150, may include a material having a low work function, such as a metal, an alloy, an electrically conductive compound, or any combination thereof.

[0467] The second electrode 150 may include lithium (Li), silver (Ag), magnesium (Mg), aluminum (AI), aluminum-lithium (AlLi), calcium (Ca), magnesium-indium (Mg-In), magnesium-silver (MgAg), ytterbium (Yb), silver-ytterbium (AgYb), ITO, IZO, or any combination thereof. The second electrode 150 may be a transmissive electrode, a semi-transmissive electrode, or a reflective electrode.

[0468] The second electrode 150 may have a single-layer structure or a multilayer structure.

[Capping Layer]

[0469] The light-emitting device 10 may include a first capping layer outside the first electrode 110, and/or the second capping layer outside the second electrode 150. In an embodiment, 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.

[0470] Light generated in the emission layer of the interlayer 130 of the light-emitting device 10 may be extracted toward the outside through the first electrode 110 which may be a semi-transmissive electrode or a transmissive electrode, and through the first capping layer. Light generated in the emission layer of the interlayer 130 of the light-emitting device 10 may be extracted toward the outside through the second electrode 150 which may be a semi-transmissive electrode or a transmissive electrode, and through the second capping layer.

[0471] The first capping layer and the second capping layer may each increase external emission efficiency according to the principle of constructive interference. Accordingly, the light extraction efficiency of the light-emitting device 10 is increased, such that the luminescence efficiency of the light-emitting device 10 may be increased.

[0472] The first capping layer and the second capping layer may each include a material having a refractive index greater than or equal to about 1.6 (with respect to a wavelength of about 589 nm).

[0473] 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.

[0474] At least one of the first capping layer and the second capping layer may each independently include a carbocyclic compound, a heterocyclic compound, an amine group-containing compound, a porphine derivative, a phthalocyanine derivative, a naphthalocyanine derivative, an alkali metal complex, an alkaline earth metal complex, or any combination thereof. The carbocyclic compound, the heterocyclic compound, and the amine group-containing compound may each optionally be substituted with a substituent including O, N, S, Se, Si, F, C.sub.1, Br, I, or any combination thereof. In an embodiment, at least one of the first capping layer and the second capping layer may each independently include an amine group-containing compound.

[0475] In an embodiment, at least one of the first capping layer and the second capping layer may each independently include a compound represented by Formula 201, a compound represented by Formula 202, or any combination thereof.

[0476] In an embodiment, 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, NPB, or any combination thereof:

##STR00207## ##STR00208##

[Film]

[0477] At least one of the first compound to the fourth compound may be included in various films. According to embodiments, an embodiment provides a film that may include at least one of the first compound to the fourth compound. The film may be, for example, an optical member (or a light control means)(for example, a color filter, a color conversion member, a capping layer, a light extraction efficiency enhancement layer, a selective light absorbing layer, a polarizing layer, a quantum dot-containing layer, or like), a light-blocking member (for example, a light reflective layer, a light absorbing layer, or the like), or a protective member (for example, an insulating layer, a dielectric layer, or the like).

[Electronic Apparatus]

[0478] The light-emitting device may be included in various electronic apparatuses. For example, the electronic apparatus including the light-emitting device may be a light-emitting apparatus, an authentication apparatus, and the like.

[0479] The electronic apparatus (for example, a light-emitting 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 arranged in at least one traveling direction of light emitted from the light-emitting device. For example, the light emitted from the light-emitting device may be blue light or white light. The light-emitting device may be a light-emitting device as described herein. In an embodiment, the color conversion layer may include quantum dots. The quantum dots may be, for example, quantum dots as described herein.

[0480] 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.

[0481] A pixel-defining film may be arranged between the subpixel areas to define each subpixel.

[0482] The color filter may further include color filter areas and light-shielding patterns arranged between the color filter areas, and the color conversion layer may further include color conversion areas and light-shielding patterns arranged between the color conversion areas.

[0483] 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, wherein the first color light, the second color light, and/or the third color light may have different maximum emission wavelengths from one another. In an embodiment, 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 an embodiment, the color filter areas (or the color conversion areas) may include quantum dots. In an embodiment, the first area may include red quantum dots, the second area may include green quantum dots, and the third area may not include quantum dots. The quantum dots may be quantum dots as described herein. The first area, the second area, and/or the third area may each further include a scatterer.

[0484] In an embodiment, the light-emitting device may emit first light, the first area may absorb the first light to emit first-first color light, the second area may absorb the first light to emit second-first color light, and the third area may absorb the first light to emit third-first color light. In an embodiment, the first-first color light, the second-first color light, and the third-first color light may have different maximum emission wavelengths from one another. In an embodiment, the first light may be blue light, the first-first color light may be red light, the second-first color light may be green light, and the third-first color light may be blue light.

[0485] The electronic apparatus may further include a thin-film transistor, in addition to the light-emitting device as described above. The thin-film transistor may include a source electrode, a drain electrode, and an active layer, wherein any one of the source electrode and the drain electrode may be electrically connected to any one of the first electrode and the second electrode of the light-emitting device.

[0486] The thin-film transistor may further include a gate electrode, a gate insulating film, and the like.

[0487] The active layer may include crystalline silicon, amorphous silicon, an organic semiconductor, an oxide semiconductor, and the like.

[0488] The electronic apparatus may further include a sealing portion for sealing the light-emitting device. The sealing portion may be arranged between the color filter and/or the color conversion layer and the light-emitting device. The sealing portion allows light from the light-emitting device to be extracted to the outside, and may prevent ambient air and moisture from penetrating into the light-emitting device. The sealing portion may be a sealing substrate including a transparent glass substrate or a plastic substrate. The sealing portion may be a thin-film encapsulation layer including at least one layer of an organic layer and/or an inorganic layer. When the sealing portion is a thin film encapsulation layer, the electronic apparatus may be flexible.

[0489] Various functional layers may be further included on the sealing portion, in addition to the color filter and/or the color conversion layer, according to the use of the electronic apparatus. Examples of the functional layers may include a touch screen layer and a polarizing layer. The touch screen layer may be a pressure-sensitive touch screen layer, a capacitive touch screen layer, or an infrared touch screen layer. The authentication apparatus may be, for example, a biometric authentication apparatus that authenticates an individual by using biometric information of a living body (for example, fingertips, pupils, etc.).

[0490] The authentication apparatus may further include, in addition to the light-emitting device as described above, a biometric information collector.

[0491] The electronic apparatus may be applied to various displays, light sources, lighting, personal computers (for example, a mobile personal computer), mobile phones, digital cameras, electronic organizers, electronic dictionaries, electronic game machines, medical instruments (for example, electronic thermometers, sphygmomanometers, blood glucose meters, pulse measurement devices, pulse wave measurement devices, electrocardiogram displays, ultrasonic diagnostic devices, or endoscope displays), fish finders, various measuring instruments, meters (for example, meters for a vehicle, an aircraft, and a vessel), projectors, and the like.

[Electronic Equipment]

[0492] The light-emitting device may be included in various electronic equipment.

[0493] In an embodiment, the electronic equipment including the light-emitting device may be a flat panel display, a curved display, a computer monitor, a medical monitor, a television, a billboard, an indoor light, an outdoor light, a signal light, a head-up display, a fully transparent display, a partially transparent display, a flexible display, a rollable display, a foldable display, a stretchable display, a laser printer, a telephone, a mobile phone, a tablet personal computer, a phablet, a personal digital assistant (PDA), a wearable device, a laptop computer, a digital camera, a camcorder, a viewfinder, a micro display, a three-dimensional (3D) display, a virtual reality display, an augmented reality display, a vehicle, a video wall including multiple displays tiled together, a theater screen, a stadium screen, a phototherapy device, or a signboard.

[0494] Since the light-emitting device has excellent effects in terms of luminescence efficiency long lifespan, the electronic equipment including the light-emitting device may have characteristics with high luminance, high resolution, and low power consumption.

[Description of FIGS. 2 and 3]

[0495] FIG. 2 is a schematic cross-sectional view of an electronic apparatus according to an embodiment.

[0496] The electronic apparatus (for example, a light-emitting apparatus) of FIG. 2 may include a substrate 100, a thin-film transistor (TFT), a light-emitting device, and an encapsulation portion 300 that seals the light-emitting device.

[0497] The substrate 100 may be a flexible substrate, a glass substrate, or a metal substrate. A buffer layer 210 may be arranged on the substrate 100. The buffer layer 210 may prevent penetration of impurities through the substrate 100 and may provide a flat surface on the substrate 100.

[0498] A TFT may be arranged on the buffer layer 210. The TFT may include an active layer 220, a gate electrode 240, a source electrode 260, and a drain electrode 270.

[0499] The active layer 220 may include an inorganic semiconductor, such as silicon or polysilicon, an organic semiconductor, or an oxide semiconductor, and may include a source region, a drain region, and a channel region.

[0500] A gate insulating film 230 for insulating the active layer 220 from the gate electrode 240 may be arranged on the active layer 220, and the gate electrode 240 may be arranged on the gate insulating film 230.

[0501] An interlayer insulating film 250 may be arranged on the gate electrode 240. The interlayer insulating film 250 may be arranged between the gate electrode 240 and the source electrode 260 to insulate the gate electrode 240 from the source electrode 260 and between the gate electrode 240 and the drain electrode 270 to insulate the gate electrode 240 from the drain electrode 270.

[0502] The source electrode 260 and the drain electrode 270 may be arranged on the interlayer insulating film 250. The interlayer insulating film 250 and the gate insulating film 230 may be formed to expose the source region and the drain region of the active layer 220, and the source electrode 260 and the drain electrode 270 may respectively contact the exposed portions of the source region and the drain region of the active layer 220.

[0503] The TFT may be electrically connected to a light-emitting device to drive the light-emitting device, and may be covered and protected by a passivation layer 280. The passivation layer 280 may include an inorganic insulating film, an organic insulating film, or any combination thereof. A light-emitting device may be provided on the passivation layer 280. The light-emitting device may include the first electrode 110, the interlayer 130, and the second electrode 150.

[0504] The first electrode 110 may be arranged on the passivation layer 280. The passivation layer 280 may not completely cover the drain electrode 270 and may expose a portion of the drain electrode 270. The first electrode 110 may be electrically connected to the exposed portion of the drain electrode 270.

[0505] A pixel-defining film 290 including an insulating material may be arranged on the first electrode 110. The pixel-defining film 290 may expose a region of the first electrode 110, and the interlayer 130 may be formed on the exposed region of the first electrode 110. The pixel-defining film 290 may be a polyimide-based organic film or a polyacrylic organic film. Although not shown in FIG. 2, at least some layers of the interlayer 130 may extend beyond the upper portion of the pixel-defining film 290 to be provided in the form of a common layer.

[0506] The second electrode 150 may be arranged on the interlayer 130, and a capping layer 170 may be further included on the second electrode 150. The capping layer 170 may be formed to cover the second electrode 150.

[0507] The encapsulation portion 300 may be located on the capping layer 170. The encapsulation portion 300 may be disposed on a light-emitting device to protect the light-emitting device from moisture and/or oxygen. The encapsulation portion 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 polyethylene terephthalate, polyethylene naphthalate, polycarbonate, polyimide, polyethylene sulfonate, polyoxymethylene, polyarylate, hexamethyldisiloxane, an acrylic resin (for example, polymethyl methacrylate, polyacrylic acid, or the like), an epoxy-based resin (for example, aliphatic glycidyl ether (AGE), or the like), or any combination thereof; or any combination of the inorganic film and the organic film.

[0508] FIG. 3 is a schematic cross-sectional view of an electronic apparatus according to another embodiment.

[0509] The electronic apparatus (for example, a light-emitting apparatus) of FIG. 3 may differ from the electronic apparatus of FIG. 2, at least in that a light-shielding pattern 500 and a functional region 400 are further included on the encapsulation portion 300. The functional region 400 may be a color filter area, a color conversion area, or a combination of the color filter area and the color conversion area. In an embodiment, the light-emitting device included in the electronic apparatus of FIG. 3 may be a tandem light-emitting device.

[Description of FIG. 4]

[0510] FIG. 4 is a schematic perspective view of an electronic equipment 1 including a light-emitting device according to an embodiment. The electronic equipment 1 may be, as an apparatus that displays a moving image or a still image, may not only be a portable electronic equipment, such as a mobile phone, a smartphone, a tablet personal computer (PC), a mobile communication terminal, an electronic notebook, an electronic book, a portable multimedia player (PMP), a navigation device, or a ultra-mobile PC(UMPC), but may also be various products, such as a television, a laptop, a monitor, a billboard, or an Internet of things (IoT). The electronic equipment 1 may be any product as described above or a part thereof. The electronic equipment 1 may be a wearable device, such as a smart watch, a watch phone, a glasses-type display, or a head mounted display (HMD), or a part of the wearable device. However, embodiments are not limited thereto.

[0511] In an embodiment, the electronic equipment 1 may be a dashboard of a vehicle, a center information display (CID) arranged on a center fascia or dashboard of a vehicle, a room mirror display instead of a side-view mirror of a vehicle, an entertainment for a back seat of a vehicle, or arranged on the back of a front seat of a vehicle, a head up display (HUD) installed in the front of a vehicle or projected on a front window glass, or a computer generated hologram augmented reality head up display (CGH AR HUD). FIG. 4 illustrates a case in which the electronic equipment 1 is a smartphone for convenience of explanation.

[0512] The electronic equipment 1 may include a display area DA and a non-display area NDA outside the display area DA. A display apparatus may implement an image through a two-dimensional array of pixels that are arranged in the display area DA.

[0513] The non-display area NDA may be an area that does not display an image, and may surround the display area DA. A driver for providing electrical signals or power to display devices arranged on the display area DA may be arranged in the non-display area NDA. A pad, which is an area to which an electronic element or a printed circuit board, may be electrically connected may be arranged in the non-display area NDA.

[0514] In the electronic equipment 1, a length in an x-axis direction and a length in a y-axis direction may be different from each other. In an embodiment, as shown in FIG. 4, a length in the x-axis direction may be less than a length in the y-axis direction. In an embodiment, a length in the x-axis direction may be the same as a length in the y-axis direction. In an embodiment, a length in the x-axis direction may be greater than a length in the y-axis direction.

[Description of FIGS. 5 and 6A to 6C]

[0515] FIG. 5 is a schematic perspective view of an exterior of a vehicle 1000 as an electronic equipment including a light-emitting device, according to an embodiment. FIGS. 6A to 6C are each a schematic diagram of an interior of the vehicle 1000 according to embodiments.

[0516] Referring to FIGS. 5, 6A, 6B, and 6C, the vehicle 1000 may include various apparatuses for moving a subject to be transported, such as a person, an object, or an animal, from a departure point to a destination point. The vehicle 1000 may include a vehicle traveling on a road or track, a vessel moving over the sea or river, an airplane flying in the sky using the action of air, and the like.

[0517] The vehicle 1000 may travel on a road or a track. The vehicle 1000 may move in a selectable direction according to the rotation of at least one wheel. Examples of the vehicle 1000 may include a three-wheeled or four-wheeled vehicle, a construction machine, a two-wheeled vehicle, a prime mover device, a bicycle, and a train running on a track.

[0518] The vehicle 1000 may include a vehicle body having an interior and an exterior, and a chassis that is a portion excluding the body in which mechanical apparatuses for driving are installed as other parts. The exterior of the vehicle body may include a front panel, a bonnet, a roof panel, a rear panel, a trunk, a pillar provided at a boundary between doors, and the like. The chassis of the vehicle 1000 may include a power generating device, a power transmitting device, a driving device, a steering device, a braking device, a suspension device, a transmission device, a fuel device, front and rear wheels, left and right wheels, and the like.

[0519] The vehicle 1000 may include a side window glass 1100, a front window glass 1200, a side-view mirror 1300, a cluster 1400, a center fascia 1500, a passenger seat dashboard 1600, and a display apparatus 2.

[0520] The side window glass 1100 and the front window glass 1200 may be partitioned by a pillar arranged between the side window glass 1100 and the front window glass 1200.

[0521] The side window glass 1100 may be installed on a side of the vehicle 1000. In an embodiment, the side window glass 1100 may be installed on a door of the vehicle 1000. Multiple side window glasses 1100 may be provided and may face each other. In an embodiment, the side window glass 1100 may include a first side window glass 1110 and a second side window glass 1120. In an embodiment, the first side window glass 1110 may be arranged adjacent to the cluster 1400 and the second side window glass 1120 may be arranged adjacent to the passenger seat dashboard 1600.

[0522] In an embodiment, the side window glasses 1100 may be spaced apart from each other in an x direction or a x direction. In an embodiment, the first side window glass 1110 and the second side window glass 1120 may be spaced apart from each other in the x direction or the x direction. For example, a virtual straight line L connecting the side window glasses 1100 may extend in the x direction or the x direction. In an embodiment, a virtual straight line L connecting the first side window glass 1110 and the second side window glass 1120 to each other may extend in the x direction or the x direction.

[0523] The front window glass 1200 may be installed in front of the vehicle 1000. The front window glass 1200 may be arranged between the side window glasses 1100 facing each other.

[0524] The side-view mirror 1300 may provide a rear view of the vehicle 1000. The side-view mirror 1300 may be installed on the exterior of the vehicle body. In an embodiment, multiple side-view mirrors 1300 may be provided. One of the side-view mirrors 1300 may be arranged outside the first side window glass 1110 and another of the side-view mirrors 1300 may be arranged outside the second side window glass 1120.

[0525] The cluster 1400 may be arranged in front of the steering wheel. The cluster 1400 may include a tachometer, a speedometer, a coolant thermometer, a fuel gauge turn indicator, a high beam indicator, a warning light, a seat belt warning light, an odometer, a tachograph, an automatic shift selector indicator light, a door open warning light, an engine oil warning light, and/or a low fuel warning light.

[0526] The center fascia 1500 may include a control panel on which buttons for adjusting an audio device, an air conditioning device, and a seat heater are disposed. The center fascia 1500 may be arranged on one side of the cluster 1400.

[0527] The passenger seat dashboard 1600 may be spaced apart from the cluster 1400 with the center fascia 1500 arranged therebetween. In an embodiment, the cluster 1400 may be arranged to correspond to a driver seat (not shown), and the passenger seat dashboard 1600 may be arranged to correspond to a passenger seat (not shown). In an embodiment, the cluster 1400 may be adjacent to the first side window glass 1110, and the passenger seat dashboard 1600 may be adjacent to the second side window glass 1120.

[0528] In an embodiment, the display apparatus 2 may include a display panel 3, and the display panel 3 may display an image. The display apparatus 2 may be arranged inside the vehicle 1000. In an embodiment, the display apparatus 2 may be arranged between the side window glasses 1100 facing each other. The display apparatus 2 may be arranged on at least one of the cluster 1400, the center fascia 1500, and the passenger seat dashboard 1600.

[0529] The display apparatus 2 may include an organic light-emitting display, an inorganic electroluminescent display, a quantum dot display, and the like. Hereinafter, as the display apparatus 2 according to an embodiment, an organic light-emitting display apparatus including the light-emitting device will be described as an example. However, various types of display apparatuses as described above may be used in embodiments.

[0530] Referring to FIG. 6A, the display apparatus 2 may be arranged on the center fascia 1500. In an embodiment, the display apparatus 2 may display navigation information. In an embodiment, the display apparatus 2 may display information regarding audio settings, video videos, or vehicle settings.

[0531] Referring to FIG. 6B, the display apparatus 2 may be arranged on the cluster 1400. The cluster 1400 may display driving information and the like through the display apparatus 2. For example, the cluster 1400 may digitally implement driving information. The digital cluster 1400 may display vehicle information and driving information as images. In an embodiment, a needle and a gauge of a tachometer and various warning light icons may be displayed by a digital signal.

[0532] Referring to FIG. 6C, the display apparatus 2 may be arranged on the passenger seat dashboard 1600. The display apparatus 2 may be embedded in the passenger seat dashboard 1600 or arranged on the passenger seat dashboard 1600. In an embodiment, the display apparatus 2 arranged on the passenger seat dashboard 1600 may display an image related to information displayed on the cluster 1400 and/or information displayed on the center fascia 1500. In an embodiment, the display apparatus 2 arranged on the passenger seat dashboard 1600 may display information that is different from information displayed on the cluster 1400 and/or information displayed on the center fascia 1500.

[Manufacturing Method]

[0533] The layers constituting the hole transport region, the emission layer, and the layers constituting the electron transport region may be formed in a selected region by using various methods such as vacuum deposition, spin coating, casting, Langmuir-Blodgett (LB) deposition, ink-jet printing, laser-printing, laser-induced thermal imaging, and the like.

[0534] When the layers constituting the hole transport region, the emission layer, and the layers constituting the electron transport region are formed by vacuum deposition, the 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 10-8 torr to about 10-3 torr, and at a deposition speed in a range of about 0.01 /see to about 100 /see, depending on a material to be included in a layer to be formed and the structure of a layer to be formed.

Definitions of Terms

[0535] The term C.sub.3-C.sub.60 carbocyclic group as used herein may be a cyclic group consisting of carbon atoms as the only ring-forming atom and having three to sixty carbon atoms, and the term C.sub.1-C.sub.60 heterocyclic group as used herein may be a cyclic group that has one to sixty carbon atoms and further includes, in addition to the carbon atoms, a heteroatom as a ring-forming atom. 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 two or more rings are condensed with each other. In an embodiment, a C.sub.1-C.sub.60 heterocyclic group may have 3 to 61 ring-forming atoms.

[0536] The term cyclic group as used herein may be a C.sub.5-C.sub.60 carbocyclic group or a C.sub.1-C.sub.60 heterocyclic group.

[0537] The term IT electron-rich C.sub.3-C.sub.60 cyclic group as used herein may be a cyclic group that has three to sixty carbon atoms and may not include *N* as a ring-forming moiety, and the term electron-deficient nitrogen-containing C.sub.1-C.sub.60 cyclic group as used herein may be a heterocyclic group that has one to sixty carbon atoms and may include *N* as a ring-forming moiety.

[0538] In an embodiment, [0539] C.sub.3-C.sub.60 carbocyclic group may be a T1 group or a group in which two or more of T1 groups may be condensed with each other (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), [0540] a C.sub.1-C.sub.60 heterocyclic group may be a T2 group, a group in which two or more T2 groups are condensed with each other, or a group in which at least one T2 group and at least one T1 group are condensed with each other (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 benzonaphthothiophene 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, etc.), [0541] a electron-rich C.sub.8-C.sub.60 cyclic group may be a T1 group, a group in which two or more T1 groups are condensed with each other, a T3 group, a group in which two or more T3 groups are condensed with each other, or a group in which at least one T3 group and at least one T1 group are condensed with each other (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 benzonaphthothiophene group, a benzonaphthosilole group, a benzofurodibenzofuran group, a benzofurodibenzothiophene group, a benzothienodibenzothiophene group, or the like), [0542] a electron-deficient nitrogen-containing C.sub.1-C.sub.60 cyclic group may be a T4 group, a group in which two or more T4 groups are condensed with each other, a group in which at least one T4 group and at least one T1 group are condensed with each other, a group in which at least one T4 group and at least one T3 group are condensed with each other, or a group in which at least one T4 group, at least one T1 group, and at least one T3 group are condensed with one another (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), [0543] 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, [0544] 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, [0545] the T3 group may be a furan group, a thiophene group, a 1H-pyrrole group, a silole group, or a borole group, and [0546] 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.

[0547] The terms cyclic group, C.sub.3-C.sub.60 carbocyclic group, C.sub.1-C.sub.60 heterocyclic group, electron-rich C.sub.3-C.sub.60 cyclic group, or IT electron-deficient nitrogen-containing C.sub.1-C.sub.60 cyclic group as used herein may each be a group condensed to any cyclic group, a monovalent group, or a polyvalent group (for example, a divalent group, a trivalent group, a tetravalent group, etc.) according to the structure of a formula for which the corresponding term is used. In an embodiment, the benzene group may be a benzo group, a phenyl group, a phenylene group, or the like, which may be readily understood by those of ordinary skill in the art according to the structure of a formula including the benzene group.

[0548] Examples of a monovalent C.sub.3-C.sub.60 carbocyclic group or a monovalent C.sub.1-C.sub.60 heterocyclic group may include a C.sub.5-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 a divalent C.sub.3-C.sub.60 carbocyclic group or a 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 substituted or unsubstituted divalent non-aromatic condensed heteropolycyclic group.

[0549] The term C.sub.1-C.sub.60 alkyl group as used herein may be a linear or branched aliphatic hydrocarbon monovalent group that has one to sixty carbon atoms, and examples thereof may include a methyl group, an ethyl group, an n-propyl group, an isopropyl 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 isohexyl group, a sec-hexyl group, a tert-hexyl group, an n-heptyl group, an isoheptyl group, a sec-heptyl group, a tert-heptyl group, an n-octyl group, an isooctyl group, a sec-octyl group, a tert-octyl group, an n-nonyl group, an isononyl group, a sec-nonyl group, a tert-nonyl group, an n-decyl group, an isodecyl 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.

[0550] 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 a terminus of the C.sub.2-C.sub.60 alkyl group, and 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.

[0551] The term C.sub.2-C.sub.0 alkynyl group as used herein may be a monovalent hydrocarbon group having at least one carbon-carbon triple bond in the middle or at a terminus of the C.sub.2-C.sub.60 alkyl group, and 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.

[0552] 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 may be a C.sub.1-C.sub.60 alkyl group), and examples thereof may include a methoxy group, an ethoxy group, and an isopropyloxy group.

[0553] The term C.sub.3-C.sub.10 cycloalkyl group as used herein may be a monovalent saturated hydrocarbon cyclic group having three to ten carbon atoms, and examples thereof 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 group (or bicyclo[2.2.1]heptyl group), a bicyclo[1.1.1]pentyl group, a bicyclo[2.1.1]hexyl group, and 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.

[0554] The term C.sub.1-C.sub.10 heterocycloalkyl group as used herein may be a monovalent cyclic group that has one to ten carbon atoms and further includes, in addition to the carbon atoms, at least one heteroatom as a ring-forming atom, and 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.

[0555] The term C.sub.3-C.sub.10 cycloalkenyl group as used herein may be a monovalent cyclic group that has three to ten carbon atoms and at least one carbon-carbon double bond in the ring thereof and no aromaticity, and 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.

[0556] The term C.sub.1-C.sub.10 heterocycloalkenyl group as used herein may be a monovalent cyclic group that has one to ten carbon atoms, further includes, in addition to the carbon atoms, at least one heteroatom as a ring-forming atom, and has at least one carbon-carbon double bond in the cyclic structure thereof. Examples of a 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.

[0557] The term C.sub.6-C.sub.60 aryl group as used herein may be a monovalent group having a carbocyclic aromatic system of six to sixty carbon atoms, and the term C.sub.6-C.sub.60 arylene group as used herein may be a divalent group having a carbocyclic aromatic system of six to sixty carbon atoms. Examples of a 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 include two or more rings, the two or more respective rings may be condensed with each other.

[0558] The term C.sub.1-C.sub.60 heteroaryl group as used herein may be a monovalent group having a heterocyclic aromatic system that has one to sixty carbon atoms and further includes, in addition to the carbon atoms, at least one heteroatom as a ring-forming atom. The term C.sub.1-C.sub.0 heteroarylene group as used herein may be a divalent group having a heterocyclic aromatic system that has one to sixty carbon atoms and further includes, in addition to the carbon atoms, at least one heteroatom as a ring-forming atom. Examples of a 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 benzoquinazoline 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 include two or more rings, the two or more respective rings may be condensed with each other.

[0559] The term monovalent non-aromatic condensed polycyclic group as used herein may be a monovalent group having two or more rings condensed with each other, only carbon atoms (for example, eight to sixty carbon atoms) as ring-forming atoms, and no aromaticity in its molecular structure when considered as a whole. Examples of a 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 indeno anthracenyl group. The term divalent non-aromatic condensed polycyclic group as used herein may be a divalent group having a same structure as the monovalent non-aromatic condensed polycyclic group.

[0560] The term monovalent non-aromatic condensed heteropolycyclic group as used herein may be a monovalent group that has two or more rings condensed with each other, further includes, in addition to carbon atoms (for example, one to sixty carbon atoms), at least one heteroatom as a ring-forming atom, and has no aromaticity in its molecular structure when considered as a whole. Examples of a 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 benzoxadiazolyl group, a benzothiadiazolyl group, an imidazopyridinyl group, an imidazopyrimidinyl group, an imidazotriazinyl group, an imidazopyrazinyl group, an imidazopyridazinyl group, an indeno carbazolyl 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 a group, a benzofurodibenzofuranyl group, benzofurodibenzothiophenyl group, and a benzothienodibenzothiophenyl group. The term divalent non-aromatic condensed heteropolycyclic group as used herein may be a divalent group having a same structure as the monovalent non-aromatic condensed heteropolycyclic group.

[0561] The term C.sub.6-C.sub.60 aryloxy group as used herein may be a group represented by-O (A.sub.102)(wherein A.sub.102 may be a C.sub.6-C.sub.60 aryl group), and the term C.sub.6-C.sub.60 arylthio group as used herein may be a group represented by S(A.sub.103)(wherein A.sub.103 may be a C.sub.6-C.sub.60 aryl group).

[0562] The term C.sub.7-C.sub.60 arylalkyl group as used herein may be a group represented by -(A.sub.104)(A.sub.105)(wherein 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 heteroarylalkyl group as used herein may be a group represented by -(A.sub.106)(A.sub.107)(wherein 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).

[0563] In the specification, the group term R.sub.10a may be: [0564] deuterium, F, Cl, Br,-I, a hydroxyl group, a cyano group, or a nitro group; [0565] 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 arylalkyl group, a C.sub.2-C.sub.60 heteroarylalkyl 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; [0566] 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 arylalkyl group, or a C.sub.2-C.sub.60 heteroarylalkyl 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.5-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 arylalkyl group, a C.sub.2-C.sub.60 heteroarylalkyl 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 [0567] 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).

[0568] In the specification, the groups 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 as used herein may each independently be: hydrogen; deuterium; F; Cl; Br; I; a hydroxyl group; a cyano group; a nitro group; or 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.5-C.sub.60 carbocyclic group, a C.sub.1-C.sub.60 heterocyclic group, a C.sub.7-C.sub.60 arylalkyl group, or a C.sub.2-C.sub.60 heteroarylalkyl 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.

[0569] The term heteroatom as used herein may be any atom other than a carbon atom or a hydrogen atom. Examples of a heteroatom may include O, S, N, P, Si, B, Ge, Se, or any combination thereof.

[0570] 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).

[0571] In the specification, the term Ph refers to a phenyl group, the term Me refers to a methyl group, the term Et refers to an ethyl group, the terms ter-Bu or But each refer to a tert-butyl group, and the term OMe refers to a methoxy group.

[0572] The term biphenyl group as used herein may be a phenyl group that is 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.

[0573] The terphenyl group as used herein may be a phenyl group that is substituted with a biphenyl group. For example, the terphenyl group may be a substituted phenyl group having, as a substituent, a C.sub.6-C.sub.60 aryl group that is substituted with a C.sub.6-C.sub.60 aryl group.

[0574] The symbols * and * as used herein, unless defined otherwise, each refer to a binding site to a neighboring atom in a corresponding formula or moiety.

[0575] Herein, the terms x-axis, y-axis, and z-axis are not limited to three axes in an orthogonal coordinate system (e.g., a Cartesian coordinate system), and may be interpreted in a broader sense than the aforementioned three axes. For example, the x-axis, y-axis, and z-axis may describe axes that are orthogonal to each other, or may describe axes that are in different directions that are not orthogonal to each other.

[0576] Hereinafter, compounds according to embodiments and light-emitting devices according to embodiments will be described in detail with reference to the following Synthesis Examples and Examples. The wording B was used instead of A used in describing Synthesis Examples means that an identical molar equivalent of B was used in place of A.

SYNTHESIS EXAMPLES AND EXAMPLES

Example 1

[0577] As an anode, a Corning 15 /cm.sup.2 (1,200 ) ITO glass substrate was cut to a size of 50 mm50 mm0.7 mm, sonicated in isopropyl alcohol and pure water for 5 minutes each, and cleaned by irradiation of ultraviolet rays and exposure of ozone thereto for 30 minutes, and the glass substrate was loaded onto a vacuum deposition apparatus.

[0578] NPD was deposited on the ITO anode formed on the glass substrate to form a hole injection layer having a thickness of 300 , Compound HT3 was deposited on the hole injection layer to form a hole transport layer having a thickness of 200 , and CzSi was deposited on the hole transport layer to form an emission auxiliary layer having a thickness of 100 .

[0579] A host (Compound HTH57 and Compound ETH87 at a weight ratio of 1:1), a dopant (Compound D-01), and a sensitizer (Compound DA-10) were co-deposited on the emission auxiliary layer at a weight ratio of 80:19:1 to form an emission layer having a thickness of 200 .

[0580] TSPO1 was deposited on the emission layer to form a hole blocking layer having a thickness of 200 , Compound ET37 was deposited on the hole blocking layer to form an electron transport layer having a thickness of 300 , LiF was deposited on the electron transport layer to form an electron injection layer having a thickness of 10 , and Al was vacuum-deposited on the electron injection layer to form a LiF/Al electrode (cathode) having a thickness of 3,000 .

Example 2

[0581] A light-emitting device of Example 2 was manufactured in the same manner as in Example 1, except that, in Example 1, Compound D-02 was used instead of Compound D-01 as the dopant.

Example 3

[0582] A light-emitting device of Example 3 was manufactured in the same manner as in Example 1, except that, in Example 1, Compound DA-09 was used instead of Compound DA-10 as the sensitizer.

Comparative Example 1

[0583] A light-emitting device of Comparative Example 1 was manufactured in the same manner as in Example 3, except that, in Example 3, Compound CE1 was used instead of Compound D-01 as the dopant.

##STR00209## ##STR00210## ##STR00211## ##STR00212##

Evaluation Example 1

[0584] Characteristics of the organic light-emitting devices manufactured in Examples 1 to 3 and Comparative Example 1 were evaluated, and results thereof are shown in Tables 1 and 2.

[0585] A Forster resonance energy transfer (FRET) rate constant (K.sup.FRET) between a sensitizer and a dopant in each device was calculated through

[00001]${k_D\left[\frac{R_0}{R_{\mathrm{DA}}}\right]}^b$

(wherein k.sub.D refers to a luminescence rate constant of an energy-donating molecule, R.sub.0 refers to a Forster radius, and R.sub.DA refers to an intermolecular distance between a sensitizer and a dopant).

[0586] A Dexter electron transfer rate constant (K.sup.DET) between a sensitizer and a dopant was calculated through

[00002]$k_0\exp \left[-\frac{2\left(r-R_C\right)}{L}\right]$

(wherein R.sub.C is the closest approach distance, and L is an average Bohr radius).

[0587] An intersystem crossing rate constant (K.sup.ISC) of a sensitizer was calculated through

[00003]$\frac{1-{}_P}{{}_P}.$

[0588] A reverse intersystem crossing rate constant (K.sup.RISC) of a sensitizer was calculated through

[00004]$\frac{{}_d}{k_{\mathrm{ISC}}{}_P{}_D{}_p}.$

[0589] A luminescence rate constant (K.sub.r.sup.s) of a sensitizer was calculated as the reciprocal of the luminescence lifespan.

[0590] A Forster radius (R.sub.0) between a sensitizer and a dopant was calculated through

[00005]$R_0^6=\frac{9\left(\ln 10\right){}^2{}_D^0}{128{}^8{N}_a{n}^4}J$ [0591] (wherein K.sup.2 is an orientation factor, .sub.D.sup.0 is PLQY of an energy-donating molecule, n is a refractive index, and J is spectral overlap).

[0592] An intermolecular distance (R.sub.DA) between a sensitizer and a dopant was calculated as an average of a value obtained by measuring a distance between the centers of respective molecules by assuming that the sensitizer and the dopant, each at the same concentration as in the experiment, are spherical molecules.

[0593] As shown above, a value corresponding to each variable was calculated to determine whether Condition 1, Condition 2, Condition 4, and Condition 5 are satisfied.

K.sup.FRET>K.sub.r.sup.s[Condition 1]

R.sub.0>R.sub.DA[Condition 2]

K.sup.FRET>K.sup.ISC[Condition 4]

K.sup.RISC>K.sup.DET[Condition 5]

[0594] For each of the devices, the driving voltage at a current density of 10 mA/cm.sup.2 was measured by using a source meter (Keithley Instrument, 2400 series), and the maximum luminescence efficiency was measured by using the external quantum efficiency measurement device C.sub.9920-2-12 of Hamamatsu Photonics Inc. In evaluating the maximum luminescence efficiency, the luminance/current density was measured by using a luminance meter that was calibrated for wavelength sensitivity, and the maximum luminescence efficiency was converted by assuming an angular luminance distribution (Lambertian) which introduced a perfect reflecting diffuser. In order to measure device lifespan, values obtained by comparing a time taken to reach 95% of the initial luminance in Comparative Example 1 with those of Examples 1 to 3 were calculated.

TABLE-US-00001 TABLE 1 Condition 1 Condition 2 Condition 4 Condition 5 Sensitizer Dopant K.sup.FRET > K.sub.r.sup.s R.sub.0 > R.sub.DA K.sup.FRET > K.sup.ISC K.sup.RISC > K.sup.DET Example 1 DA-10 D-01 Example 2 DA-10 D-02 X Example 3 DA-09 D-01 X Comparative DA-09 CE1 X X X X Example 1

TABLE-US-00002 TABLE 2 Driving Relative voltage Luminescence lifespan Sensitizer Dopant (V) efficiency (%) (T.sub.95, %) Example 1 DA-10 D-01 4.6 168 218 Example 2 DA-10 D-02 4.5 124 138 Example 3 DA-09 D-01 4.5 118 120 Comparative DA-09 CE1 4.6 100 100 Example 1

Evaluation Example 2

[0595] The time-resolved photoluminescence (TPRL) spectrum of the organic light-emitting device manufactured in Example 1 was measured with excitation light of 337 nm, and a result thereof is shown in FIG. 7.

[0596] Referring to FIG. 7, it may be confirmed that after the peak, the amplitude of the third compound (sensitizer) may be greater than the amplitude of the third compound and the fourth compound (dopant).

[0597] The light-emitting device may have high efficiency and long lifespan, and an electronic apparatus including the same may have improved performance.

[0598] 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 purposes 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.