Organic semiconductor device that uses chrysene compound

Abstract

An organic semiconductor material having a chrysene skeleton by limiting a compound having particular transistor performance. The chrysene compound is represented by the following chemical formula: ##STR00001##
In the chemical formula, R2 and R8 are not the same functional group, and independently includes at least one of a hydrogen atom, a substituted or non-substituted aryl group, a substituted or non-substituted heterocyclic group and a substituted or non-substituted alkyl group.

Claims

1. An organic semiconductor material comprising a chrysene skeleton shown by the following chemical formula CF1: ##STR00007## wherein R.sup.2 and R.sup.8 each is neither a hydrogen atom nor the same functional group, and independently represents an alkyl group having 1 to 30 carbon atoms, an aryl group having 5 to 60 carbon atoms, or a heterocyclic group having 3 to 60 carbon atoms, and wherein each of said groups may have a substituent group, wherein R.sup.2 and R.sup.8 are asymmetric on the chrysene skeleton.

2. The organic semiconductor material according to claim 1, wherein said chrysene skeleton has a chrysene skeleton shown by the following chemical formula CF2: ##STR00008## wherein R.sup.2 represents an alkyl group having 1 to 30 carbon atoms, or an aryl group having 5 to 60 carbon atoms excluding a nonsubstituted phenyl group, and wherein said each of said groups may have a substituent group.

3. The organic semiconductor material according to claim 1, wherein said chrysene skeleton has a chrysene skeleton shown by the following chemical formula CF3: ##STR00009## wherein R.sup.2 and R.sup.15 each independently represents an alkyl group having 1 to 30 carbon atoms, and wherein said alkyl group may have a substituent group.

4. An organic semiconductor device comprising the organic semiconductor material according to claim 1.

5. An organic semiconductor device comprising the organic semiconductor material according to claim 2.

6. An organic semiconductor device comprising the organic semiconductor material according to claim 3.

7. An organic electronic device comprising the organic semiconductor material according to claim 1 in a combination with a plurality of additional organic semiconductor materials.

8. An organic electronic device comprising the organic semiconductor material according to claim 2 in a combination with a plurality of additional organic semiconductor materials.

9. An organic electronic device comprising the organic semiconductor material according to claim 3 in a combination with a plurality of additional organic semiconductor materials.

10. An organic semiconductor material comprising a chrysene skeleton shown by the following chemical formula CF2: ##STR00010## wherein R.sup.2 represents an alkyl group having 1 to 30 carbon atoms, wherein R.sup.2 is asymmetric on the chrysene skeleton.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 is a schematic diagram of a top contact FET;

(2) FIG. 2 is a schematic diagram of a bottom contact FET;

(3) FIG. 3 is a 1H-NMR spectrum diagram of 2-octyl-8-penylchrysene (compound B); and

(4) FIG. 4 is a 1H-NMR spectrum diagram of 2-butyl-8-(4-butylphenyl) chrysene (compound D).

DETAILED DESCRIPTION OF THE INVENTION

(5) Exemplary examples of the present invention will be shown below.

Example 1

(6) A typical synthesis (manufacture) example of an organic semiconductor material having a chrysene skeleton of the first invention will be shown below.

Synthesis (Manufacture) Method of 2-octyl-8-phenylchrysene (Compound B: Hereinafter, Referred to as P-28CR-8)

(7) Although 2,8-dibromochrysene that is a starting material is not commercially available, since it is described in from paragraphs [0040] to [0044] of the first patent application, the synthesis method thereof is omitted.

Synthesis of Compound A

(8) Under a nitrogen atmosphere, in a 30 mL three-neck flask with a cooling pipe, 1.0 g (2.59 mmol) of 2,8-dibromochrysene, 0.28 g (2.33 mmol) of phenyl boronic acid, 30 mg (0.03 mmol) of tetrakistriphenylphosphine palladium, 0.49 g (4.66 mmol) of sodium carbonate, 15 ml of toluene, and 4 ml of water were added and the mixture was stirred at 80 C. for 16 hours. After the end of the reaction, the mixture was cooled to room temperature, heptane and water were added and crystal was filtrated thereby. The resulted crude product was purified by column chromatography and recrystallization, and a compound A was obtained.

Synthesis of Compound B

(9) ##STR00005##

(10) Under a nitrogen atmosphere, in a 30 mL three-neck flask with a cooling pipe, after adding 0.089 g (3.13 mmol) of metal magnesium and 2 mL of tetrahydrofuran, 0.55 g (2.87 mmol) of 1-bromooctane was dropped, the mixture was stirred at room temperature for 1 hour, and a Grignard reagent was prepared thereby. Next, under a nitrogen atmosphere, in a 30 mL three-neck flask, 1.0 g (2.61 mmol) of the compound A, 14 mg (0.03 mmol) of [1,3-bis(diphenylphosphino)propane]dichloronickel (II), and 15 mL of tetrahydrofuran were added, and the mixture was cooled to 0 C. Subsequently, the Grignard reagent of 1-bromooctane that was prepared in advance was added, and the mixture was stirred at 0 C. for 4 hours. After the end of the reaction, dilute hydrochloric acid and heptane were added and crystal was filtrated. The resulted crude product was purified by the column chromatography and recrystallization, and a compound B was obtained thereby. A 1H-NMR spectrum of the compound B is shown in FIG. 4.

Synthesis (Manufacture) Method of 2-butyl-8-(4-butylphenyl) chrysene (Compound D: Hereinafter, referred to as 4P-28CR-4)

(11) ##STR00006##

(12) The 2,8-dibromochrysene that is a starting material is the same as described above.

Synthesis of Compound C

(13) Under a nitrogen atmosphere, in a 30 mL three-neck flask with a cooling pipe, 1.0 g (2.59 mmol) of 2,8-dibromochrysene, 0.42 g (2.33 mmol) of p-(n-butyl)phenyl boronic acid, 30 mg (0.03 mmol) of tetrakistriphenylphosphine palladium, 0.49 g (4.66 mmol) of sodium carbonate, 15 ml of toluene, and 4 ml of water were added and the mixture was stirred at 80 C. for 16 hours. After the end of reaction, the mixture was cooled to room temperature, heptane and water were added and crystal was filtrated. The resulted crude product was purified by column chromatography and recrystallization, and a compound C was obtained.

Synthesis of Compound D

(14) Under a nitrogen atmosphere, in a 30 mL three-neck flask with a cooling pipe, after adding 0.079 g (2.28 mmol) of metal magnesium and 2 mL of tetrahydrofuran, 0.34 g (2.50 mmol) of 1-bromobutane was dropped, the mixture was stirred at room temperature for 1 hour, and a Grignard reagent was prepared. Next, under a nitrogen atmosphere, in a 30 mL three-neck flask, 1.0 g (2.28 mmol) of the compound A, 12 mg (0.02 mmol) of [1,3-bis(diphenylphosphino)propane]dichloronickel (II), and 15 mL of tetrahydrofuran were added, and the mixture was cooled to 0 C. Subsequently, the Grignard reagent of 1-bromobutane that was prepared in advance was added, and the mixture was stirred at 0 C. for 4 hours. After the end of the reaction, dilute hydrochloric acid and heptane were added and crystal was filtrated. The resulted crude product was purified by the column chromatography and recrystallization, and a compound D was obtained thereby. A 1H-NMR spectrum of the compound D is shown in FIG. 5.

Example 2

(15) In order to investigate the transistor performance, the respective elements were prepared as shown below.

Preparation of Single Crystal Transistor (Casting Method)

(16) A silicon wafer on which a thermal oxide film having a thickness of 210 nm was formed (Si/SiO.sub.2 (bare)) and a silicon wafer on which a polymethyl methacrylate (PMMA) insulating film (film thickness: 30 nm) was prepared by coating a toluene solution (0.7% by weight) of PMMA according to a spin coat method (number of rotation: 2000 rpm, 30 seconds), and subsequently by heat treating at 120 C. for 4 hours were used as substrates.

(17) On these substrates, a mesitylene solution of the compound B (0.08% by weight) was cast under air, and a single crystal was prepared on the substrates.

(18) At both ends of the single crystal, after a carbon paste was coated and molded as a drain electrode, top contact type FET elements were prepared, and under reduced pressure, FET measurement was performed. In the same manner, single crystal transistor elements of the compound D were prepared.

Preparation of Organic Thin Film Transistor (Coating: Spin Coat)

(19) A thin film was prepared by spin coating (number of rotation: 2000 rpm, 30 seconds) a toluene solution of the compound B (0.4% by weight) on a substrate of the bottom contact type (d=210 nm, L=10 m, w=20 cm), and the FET measurement was performed under reduced pressure condition. According to the similar method, a thin film transistor element was prepared according to the spin coat method of the compound D.

Preparation (Vapor Deposition) of Organic Thin Film Transistor

(20) The compound B was deposited on the substrate at a thickness of 50 nm using a vacuum deposition apparatus, further thereon, gold that becomes a source, drain electrode was deposited at a thickness of 80 nm (L=50 m, W=1.5 mm) by an electron beam method, and a top contact type element was prepared thereby, and under reduced pressure condition, the FET measurement was performed. As the substrate, the silicon wafer (Si/SiO.sub.2) substrates that were respectively surface treated with polystyrene (PS) and CYTOP and a non-treated (bare) substrate were used, and organic films were prepared at room temperature, 60 and 100 C. It was found by the AFM measurement that a film thickness of the PS was 13 nm, and a film thickness of the CYTOP was 27.8 nm. In the same method, thin film transistor elements of the compound D were prepared. Here, the CYTOP is a fluororesin having an amorphous structure and transparency and is used for a coating material, an insulating film and the like.

(21) Results of measurement of performance of the respective elements prepared as described above are shown in Table 1.

(22) TABLE-US-00001 TABLE 1 Results of measurement FILM DEPOSITION INSULATING MOBILITY .sub.FET V.sub.th Compound METHOD FILM [cm.sup.2V.sup.1s.sup.1] I.sub.on/I.sub.off [V] 4P-28CR-4 CAST METHOD (SINGLE CRYSTAL) bare (S.sub.iO.sub.2) 0.6 10.sup.3 30 Compound D CAST METHOD (SINGLE CRYSTAL) PMMA 2.7 10.sup.2 23 COATING/SPIN COAT METHOD bare 4.6 10.sup.4 10.sup.4 39 VACUUM DEPOSITION METHOD/ bare 2.7 10.sup.3 10.sup.3 67 ROOM TEMPERATURE VACUUM DEPOSITION METHOD/ PS 4.3 10.sup.3 10.sup.3 33 ROOM TEMPERATURE VACUUM DEPOSITION METHOD/ SYTOP 2.8 10.sup.2 10.sup.4 48 ROOM TEMPERATURE VACUUM DEPOSITION METHOD/60 C. bare 5.8 10.sup.3 10.sup.2 61 VACUUM DEPOSITION METHOD/60 C. PS 1.8 10.sup.2 10.sup.3 36 VACUUM DEPOSITION METHOD/60 C. CYTOP 0.2 10.sup.5 51 VACUUM DEPOSITION METHOD/100 C. bare 5.0 10.sup.3 10.sup. 41 VACUUM DEPOSITION METHOD/100 C. PS 5.2 10.sup.2 10.sup.2 40 VACUUM DEPOSITION METHOD/100 C. CYTOP 9.4 10.sup.2 10.sup.3 48 P-28CR-8 CAST METHOD (SINGLE CRYSTAL) PMMA 2.0 10.sup.4 21 Compound B COATING/SPIN COAT METHOD bare 1.5 10.sup.4 10.sup.3 41 VACUUM DEPOSITION METHOD/ bare 9.5 10.sup.3 10.sup.4 54 ROOM TEMPERATURE VACUUM DEPOSITION METHOD/ PS 0.1 10.sup.4 24 ROOM TEMPERATURE VACUUM DEPOSITION METHOD/ SYTOP 0.5 10.sup.4 43 ROOM TEMPERATURE VACUUM DEPOSITION METHOD/60 bare 5.9 10.sup.2 10.sup.5 40 VACUUM DEPOSITION METHOD/60 PS 3.9 10.sup.2 10.sup.4 29 VACUUM DEPOSITION METHOD/60 CYTOP 2.2 10.sup.5 65 VACUUM DEPOSITION METHOD/100 bare 0.1 10.sup.3 80 VACUUM DEPOSITION METHOD/100 PS 0.4 10.sup.4 56 VACUUM DEPOSITION METHOD/100 CYTOP 3.1 10.sup.4 57 Numerical values particularly excellent in the mobility are shown with an underline.

INDUSTRIAL APPLICABILITY

(23) The invention according to the present application shows particular transistor performance as shown above and can be expected to be widely used as the organic semiconductor material.

EXPLANATION OF REFERENCE NUMERALS

(24) 1: TOP CONTACT TYPE FET 2: BOTTOM CONTACT TYPE FET 3: SOURCE 4: DRAIN 5: ORGANIC SEMICONDUCTOR 6: INSULATING FILM 7: SUBSTRATE (GATE)