WO2006090569A1

WO2006090569A1 - Organic semiconductor material, organic semiconductor film, organic semiconductor device, organic thin-film transistor, field effect transistor and switching device

Info

Publication number: WO2006090569A1
Application number: PCT/JP2006/301959
Authority: WO
Inventors: Chiyoko Takemura; Rie Katakura; Tatsuo Tanaka; Katsura Hirai
Original assignee: Konica Minolta Holdings, Inc.
Priority date: 2005-02-24
Filing date: 2006-02-06
Publication date: 2006-08-31
Also published as: JPWO2006090569A1

Abstract

Disclosed is an organic semiconductor material having good characteristics as transistor including deterioration over time which can be easily formed into a thin film by coating. Also disclosed are an organic semiconductor film using such an organic semiconductor material, an organic semiconductor device, an organic thin-film transistor, a filed effect transistor and a switching device using such a transistor. Specifically disclosed is an organic semiconductor material containing a compound represented by the following general formula (1). [Chemical formula] (1) (In the formula, X1-X4 respectively represent a substituent; R1-R8 respectively represent a hydrogen atom or a substituent; and n1-n4 respectively represent an integer of 0-5. When all n1-n4 are 0, all R1-R8 are not hydrogen atoms and at least one of them is a substituent.)

Description

Specification

Organic semiconductor materials, organic semiconductor films, organic semiconductor elements, organic thin film transistors, field effect transistors, and switching elements

Technical field

The present invention relates to an organic semiconductor material, an organic semiconductor film using the same, an organic semiconductor element, an organic thin film transistor, a field effect transistor, and a switching element using the transistor.

Background art

With the widespread use of information terminals, there is an increasing need for flat panel displays as computer displays. In addition, with the progress of computerization, the information provided by paper media has increased in opportunities to be provided electronically. As a display medium for mopile that is thin, light and easy to carry, electronic paper can be used. Or there is a growing need for digital paper.

[0003] Generally, in a flat panel display device, a display medium is formed using an element using liquid crystal, organic EL, electrophoresis, or the like. In such display media, in order to ensure uniformity of screen brightness, screen rewriting speed, etc., the technology that uses TFT elements that are active drives as image drive elements has become the mainstream. For example, in an ordinary computer display, these TFT elements are formed on a glass substrate, and liquid crystal, organic EL elements, etc. are sealed.

Here, semiconductors such as a—Si (amorphous silicon) and p—Si (polysilicon) can be mainly used for TFT elements, and these S 泮 conductors (and metal films as required) can be used. TFT elements are manufactured by forming multiple layers and forming source, drain, and gate electrodes sequentially on the substrate. The manufacture of such TFT elements usually requires sputtering and other vacuum manufacturing processes.

[0005] However, in the manufacture of such a TFT element, the vacuum system manufacturing process including the vacuum chamber must be repeated many times to form each layer, resulting in extremely high equipment costs and running costs. It was huge. For example, in TFT elements, the shape of each layer is usually For this purpose, it is necessary to repeat processes such as vacuum deposition, dope, photolithography, and development many times, and elements are formed on the substrate through tens of processes. For the semiconductor portion that is the key to the switching operation, multiple types of semiconductor layers such as p-type and n-type are stacked. In such a conventional manufacturing method using Si semiconductors, it is not easy to change the equipment because the design of a manufacturing apparatus such as a vacuum chamber needs to be drastically changed in response to the need to increase the size of the display screen.

[0006] In addition, since the formation of a TFT element using such a conventional Si material includes a process at a high temperature, the substrate material is limited to a material that can withstand the process temperature. Become. For this reason, in practice, glass must be used, and when the above-mentioned electronic paper or digital paper! /, And a thin display using such a conventionally known TFT element are used, the display Will be heavy and inflexible, and may be broken by the impact of a drop. These characteristics resulting from the formation of TFT elements on a glass substrate are undesirable in meeting the need for easy-to-use thin-type displays with the progress of computerization.

[0007] On the other hand, research on organic semiconductor materials has been energetically advanced in recent years as an organic compound having a high charge transporting property. These compounds are not only charge transport materials for organic EL devices, but also organic laser oscillation devices such as those discussed in Science, 289 サイエンス, 599 (2000), etc. It is expected to be applied to organic thin-film transistors that have been reported in a number of papers such as (Nature), April 03, 521 (2000). If these organic semiconductor devices can be realized, there is a possibility of obtaining a semiconductor that can be dissolved by simplifying the manufacturing process by vacuum or low-pressure deposition at a relatively low temperature and further improving its molecular structure appropriately. It can be considered that the organic semiconductor solution is made into an ink by a printing method including an ink jet method. Manufacturing by these low-temperature processes has been considered impossible for conventional Si-based semiconductor materials, but devices using organic semiconductors have the potential, and thus the above-mentioned limitations on substrate heat resistance are present. There is a possibility that, for example, a TFT element can be formed on a transparent resin substrate. If a TFT element is formed on a transparent resin substrate and the display material can be driven by the TFT element, the display will be It is lighter and more flexible than the ones, and it can be a display that does not crack (or very hard to break) when dropped.

[0008] As organic semiconductor materials, poly-ethylene biylene, polypyrrole, polythiophene, oligothiophene, pentacene and the like have been studied. Especially, the polyacene compounds such as pentacene have high carrier mobility. It has been reported that semiconductor device characteristics can be obtained. Also, polyacene compounds or polyacene compound derivatives are disclosed (see, for example, Patent Documents 1 to 4 and Non-Patent Document 1), all of which are suitable for solution process suitability, carrier mobility, and semiconductor device characteristics. It is not enough in terms of compatibility, and further development of organic semiconductor materials is desired!

Patent Document 1: Pamphlet of International Publication No. 03Z16599

Patent Document 2: Pamphlet of International Publication No. 03Z28125

Patent Document 3: U.S. Pat.No. 6,690,029

Patent Document 4: Japanese Unexamined Patent Application Publication No. 2004-107216

Non-Patent Document 1: Science, 303, pp. 1644–1646 (2004) Disclosure of Invention

Problems to be solved by the invention

[0009] An object of the present invention is to provide an organic semiconductor material that has good characteristics as a transistor including deterioration over time and that can be easily formed into a thin film by coating, an organic semiconductor film using the organic semiconductor material, an organic semiconductor element, an organic thin film transistor, and It is an object to provide a field effect transistor and a switching element using the transistor.

Means for solving the problem

[0010] The above object of the present invention has been achieved by the following constitution.

[0011] 1. An organic semiconductor material comprising a compound represented by the following general formula (1): [0012] [Chemical Formula 1] General formula (1 »

[Wherein, X to X each represents a substituent, and R to R represent a hydrogen atom or a substituent, respectively.

1 4 1 8

Represents. nl to n4 each represents an integer of 0 to 5. However, when nl to n4 are all 0, R

1

~ R

At least one of 8 is a substituent, not all hydrogen atoms. )

2. The organic semiconductor material as described in 1 above, wherein the general formula (1) is represented by the following general formula (2).

[0014] [Chemical formula 2] General formula (2)

1 8 1 8

Represents. nl ~! ι4 represents an integer of 0 to 4, respectively. )

3. In the general formula (1), nl to n4 are all 0, and R, R, R, and R are

1 4 5 8

Wherein R, R, R, and R are each a hydrogen atom.

2 3 6 7

The organic semiconductor material described.

[0016] 4. In the general formula (1), nl to n4 are all 0, and one of R and R is an alkyl group And the other is a hydrogen atom, one of R and R is an alkyl group and the other is a hydrogen atom

4 5

2. The organic semiconductor material as described in 1 above.

[0017] 5. The organic semiconductor material as described in 2 above, wherein in the general formula (2), nl to n4 are all 0.

[0018] 6. In the general formula (2),! /, X, X, X, and X are each an alkyl group.

5 6 7 8

6. The organic semiconductor material as described in 2 or 5 above.

[0019] 7. In the general formula (2), one of X and X is an alkyl group and the other is a hydrogen atom.

5 6

Wherein X is an alkyl group and the other is a hydrogen atom.

7 8

5. The organic semiconductor material according to 5.

[0020] 8. In the general formula (2),! /, R, R, R, and R are each an alkyl group, and R, R

1 4 5 8 2 3

, R, and R are each a hydrogen atom.

6 7

The organic semiconductor material described.

[0021] 9. In the general formula (2), one of R and R is an alkyl group and the other is a hydrogen atom.

1 8

2, 5-7, wherein one of R, R and R is an alkyl group and the other is a hydrogen atom

4 5

The organic semiconductor material according to item 1 above.

[0022] 10. An organic semiconductor film comprising the organic semiconductor material according to any one of 1 to 9 above.

[0023] 11. An organic semiconductor element comprising the organic semiconductor material according to any one of 1 to 9 above.

[0024] 12. An organic thin film transistor comprising the organic semiconductor material according to any one of 1 to 9 in a semiconductor layer.

[0025] 13. A field-effect transistor comprising the organic semiconductor material according to any one of 1 to 9 above in a semiconductor layer.

[0026] 14. A switching element comprising the organic thin film transistor according to 12 or the field effect transistor according to 13.

The invention's effect

[0027] According to the present invention, an organic semiconductor material that has good characteristics as a transistor including deterioration with time and that can be easily formed into a thin film by coating, an organic semiconductor film using the organic semiconductor material, and an organic semiconductor It was possible to provide a body element, an organic thin film transistor, a field effect transistor, and a switching element for the transistor.

Brief Description of Drawings

FIG. 1 is a diagram showing a configuration example of a field effect organic thin film transistor using an organic semiconductor material for an active layer.

Explanation of symbols

[0029] 1 Active layer

2 Source electrode

3 Drain electrode

4 Gate electrode

5 Insulation layer

6 Support

BEST MODE FOR CARRYING OUT THE INVENTION

[0030] Hereinafter, the present invention will be described in detail.

In the general formula (1), X to X each represents a substituent, and examples of the substituent are

14

Alkyl groups (eg, methyl, ethyl, propyl, isopropyl, tert-butyl, pentyl, hexyl, octyl, dodecyl, tridecyl, tetradecyl, pentadecyl, etc.), A cycloalkyl group (for example, a cyclopentyl group, a cyclohexyl group, etc.), an alkenyl group (for example, a buyl group, an aryl group, etc.), an alkynyl group (for example, an ethynyl group, a propargyl group, etc.), an aryl group (for example, a phenyl group). , Naphthyl group, etc.), heteroaryl group (for example, furyl group, chael group, pyridyl group, pyridazyl group, pyrimidyl group, virazyl group, triazyl group, imidazolyl group, pyrazolyl group, thiazolyl group, benzoimidazolyl group, Benzoxazolyl group, quinazolyl group, phthalazyl group, etc.), heterocyclic group (for example, pyrrolidini Group, imidazolidinyl group, morpholinyl group, oxazolidyl group, etc.), alkoxy group (for example, methoxy group, ethoxy group, propyloxy group, pentyloxy group, hexyloxy group, octyloxy group, dodecyloxy group, etc.), cycloalkoxy group (for example, , Cyclopentyloxy group, cyclohexyloxy group, etc.), aryloxy group (eg, phenoxy group, naphthyloxy group, etc.), alkylthio group (eg, methoxy) Ruthio group, ethylthio group, propylthio group, pentylthio group, hexylthio group, octylthio group, dodecylthio group, etc.), cycloalkylthio group (eg, cyclopentylthio group, cyclohexylthio group, etc.), arylthio group (eg, phenol- Ruthio group, naphthylthio group, etc.), alkoxy carbo yl group (for example, methyloxy carbo yl group, ethyloxy carbonyl group, butyloxy carbonyl group, octyloxy carbonyl group, dodecyloxy carbo Group), aryloxycarbonyl group (for example, phenylcarbonyl group, naphthyloxycarbonyl group, etc.), sulfamoyl group (for example, aminosulfonyl group, methylaminosulfol group). , Dimethylaminosulfol group, butyraminosulfol group, hexylaminosulfol group, cyclohexyl Ruaminosulfol group, octylaminosulfol group, dodecylaminosulfol group, phenolaminosulfol group, naphthylaminosulfol group, 2-pyridylaminosulfol group, etc.), acyl group (eg, acetyl) Group, ethyl carbonate group, propyl carbon group, pentyl carbon group, cyclohexyl carbon group, octyl carbon group, 2-ethyl hexyl carbon group, dodecyl carbon group, vinyl carbon group Group, naphthylcarbol group, pyridylcarbol group, etc.), acyloxy group (for example, acetyloxy group, ethylcarboxoxy group, butylcarboxoxy group, octylcarboxoxy group, dodecylcarbonyloxy group, phenylcarboxyl group) Group), amide group (for example, methylcarbo-lamino group, ethylcarbo-lamino group, Methyl carbolumino group, propyl carbolumino group, pentyl carbolumino group, cyclohexyl carbolumino group, 2-ethylhexyl carbolumino group, octyl carbolumino group, dodecyl carbolumino group, phenol carbolumino group , Naphthyl carboamino groups, etc.), strong rubamoyl groups (for example, amino carbo group, methyl amino carbo ol group, dimethyl amino group, propyl amino carbo ol group, pentyl amino carbo ol group) , Cyclohexylaminocarbonyl group, octylaminocarbonyl group, 2-ethylhexylaminocarbonyl group, dodecylaminocarbonyl group, phenylaminocarbonyl group, naphthylaminocarbonyl group, 2-pyridylamino Carbo group), ureido group (eg methylureido group, ethyluree group). Id group, pentylureido group, cyclohexylureido group, octylureido group, dodecylureido group, ferureureido group, naphthylureido group, 2-pyridylamido Noureid groups, etc.), sulfier groups (eg methyl sulfier groups, ethyl sulfier groups, butyl sulfier groups, cyclohexyl sulfier groups, 2-ethyl hexyl sulfier groups, dodecyl sulfir groups, phenols) Rusulfyl group, naphthylsulfuric group, 2-pyridylsulfel group, etc.), alkylsulfol group (eg, methylsulfol group, ethylsulfol group, butylsulfol group, cyclohexylsulfol group) 2-ethylhexylsulfol group, dodecylsulfol group, etc.), arylsulfol group (eg, phenylsulfol group, naphthylsulfol group, 2-pyridylsulfol group, etc.), amino Group (for example, amino group, ethylamino group, dimethylamino group, ptylamino group, cyclopentylamino group, 2-ethylhexylamino group) Group, dodecylamino group, arlino group, naphthylamino group, 2-pyridylamino group, etc.), halogen atom (eg, fluorine atom, chlorine atom, bromine atom, etc.), fluorinated hydrocarbon group (eg, fluoromethyl group, trifluoromethyl group, etc.) Chloromethyl group, pentafluoroethyl group, pentafluorophenyl group, etc.), cyano group, silyl group (for example, trimethylsilyl group, triisopropylpropyl group, triphenylsilyl group, benzylethylsilyl) These substituents may be further substituted with the above substituents, or a plurality of these may be bonded to each other to form a ring.

[0032] R to R each represent a hydrogen atom or a substituent, and examples of the substituent are X to X.

1 8 1 4 Synonymous with substituent. nl to n4 each represents an integer of 0 to 5. However, when nl to n4 are all 0, R to R are not all hydrogen atoms, that is, at least one of R to R is a substituent.

1 8 1 8

is there.

[0033] In the general formula (1), preferred compounds are those in which one of R and R when nl to n4 are all 0.

1 8 is an alkyl group and the other is a hydrogen atom, one of R and R is an alkyl group and the other is a hydrogen atom

4 5

Or R, R, R, R are each an alkyl group, and R, R, R

1 4 5 8 2 3 6

, R are compounds each being a hydrogen atom.

7

[0034] In the general formula (2), X to X represent substituents.

1 8

It is synonymous with the substituent represented by X to X in (1). R to R are each a hydrogen atom or

1 4 1 8

Represents a substituent, and the substituent has the same meaning as the substituent represented by X to x in the general formula (1).

14

It is. nl to n4 each represents an integer of 0 to 4.

[0035] In the general formula (2), a preferable compound is a compound in which nl to n4 are all 0, Preferred compounds of X, X, X, and X are each an alkyl group, or X,

5 6 7 8 5

One of X is an alkyl group and the other is a hydrogen atom, and one of X and X is an alkyl group and the other

6 7 8

Is a compound in which is a hydrogen atom. R, R, R and R are each an alkyl group,

1 4 5 8

R, R, R, R are each a hydrogen atom.

2 3 6 7 1 8

A compound in which the other is a hydrogen atom, one of R and R is an alkyl group and the other is a hydrogen atom

4 5

Is also preferable.

[0036] Specific examples of the compound represented by the general formula (1) according to the present invention are shown below, but the present invention is not limited thereto.

[0037] [Chemical 3]

[0038] [Yi 4]

[0039] The compound represented by the general formula (1) according to the present invention can be synthesized, for example, by the following method.

[0040] [Chemical 5]

General formula <1)

[0041] More specifically, Org. Chem., 55, 13, 1990, 4190-4198 can be synthesized with reference to the method described herein.

[0042] An organic thin film transistor has a source electrode and a drain electrode connected by an organic semiconductor channel (active layer) on a support, and a top gate type having a gate electrode on the gate electrode via a gate insulating layer. A bottom gate type having a gate electrode on a support and a source electrode and a drain electrode connected by an organic semiconductor channel through a gate insulating layer is roughly classified.

[0043] In order to install the compound according to the present invention in the active layer of the organic thin film transistor element, it can be placed on the substrate by vacuum vapor deposition, but it can be dissolved in an appropriate solvent, and the additive can be added as needed. It is preferable to install the prepared solution on the substrate by cast coating, spin coating, printing, ink jet method, abrasion method or the like. In this case, the solvent for dissolving the organic semiconductor material of the present invention is not particularly limited as long as it can prepare a solution having an appropriate concentration by dissolving the organic semiconductor material. Chain ether solvents such as thiol ether diisopropyl ether, cyclic ether solvents such as tetrahydrofuran and dioxane, ketone solvents such as acetone methyl ketyl ketone, halogenated forms such as chloroform and 1,2-dichloroethane Alkyl solvents, toluene, ο-dichlorobenzene, nitrobenzene, m-talesol and other aromatic solvents, hexane and other chain hydrocarbon solvents, cyclohexane and other cyclic hydrocarbon solvents, N —Methyl pyrrolidone, carbon disulfide and the like.

In the present invention, the material for forming the source electrode, the drain electrode, and the gate electrode is not particularly limited as long as it is a conductive material. Platinum, gold, silver, nickel, chromium, copper, iron, tin, anti Lead, tantalum, indium, palladium, tellurium, rhenium, iridium, aluminum, ruthenium, germanium, molybdenum, tungsten, tin oxide 'antimony, indium oxide' tin (ITO), fluorine-doped acid zinc, zinc, carbon, Graphite, glassy power, bonbon, silver paste and carbon paste, lithium, beryllium, sodium, magnesium, potassium, calcium, scandium, titanium, manganese, zirconium, gallium, niobium, sodium, sodium monopotassium alloy, magnesium, Lithium, Anorium, Magnesium Z Copper Mixture, Magnesium Z Silver Mixture, Magnesium Z Aluminum Mixture, Magnesium Z Indium Mixture, Aluminum Z Acid-Aluminum Mixture, Lithium Z Al A mixture of minium and the like is used, and platinum, gold, silver, copper, aluminum, indium, ιτο, and carbon are particularly preferable. Alternatively, a known conductive polymer whose conductivity has been improved by doping or the like, for example, conductive polyarine, conductive polypyrrole, conductive polythiophene, a complex of polyethylene dioxythiophene and polystyrene sulfonic acid, etc. is also suitably used. It is done. Of these, those having low electrical resistance on the contact surface with the semiconductor layer are preferred.

[0045] As a method for forming an electrode, a method for forming an electrode using a known photolithographic method or a lift-off method from a conductive thin film formed using a method such as vapor deposition or sputtering using the above as a raw material, aluminum, copper, or the like There is a method of etching on a metal foil using a resist by thermal transfer, ink jet or the like. Alternatively, the conductive polymer solution or dispersion, or the conductive fine particle dispersion may be directly patterned by ink jetting, or may be formed from the coating film by lithography or laser ablation. Furthermore, a method of patterning an ink containing a conductive polymer or conductive fine particles, a conductive paste, or the like by a printing method such as relief printing, intaglio printing, lithographic printing, or screen printing can also be used.

As the gate insulating layer, various insulating films can be used. In particular, an inorganic oxide film having a high relative dielectric constant is preferable. Examples of inorganic oxides include silicon oxide, aluminum oxide, tantalum oxide, titanium oxide, tin oxide, vanadium oxide, barium strontium titanate, barium zirconate titanate, lead zirconate titanate, titanate Lead lanthanum, strontium titanate, barium titanate, barium magnesium fluoride, bismuth titanate, strontium bismuth titanate, strontium bismuth tantanoate, tantanol Examples thereof include bismuth acid niobate and trioxide yttrium. Of these, preferred are silicon oxide, acid aluminum, acid tantalum, and acid titanium. Inorganic nitrides such as silicon nitride and aluminum nitride can also be suitably used.

[0047] Examples of the method for forming the coating include vacuum deposition, molecular beam epitaxy, ion cluster beam, low energy ion beam, ion plating, CVD, sputtering, and atmospheric pressure plasma. Dry process, spray coating method, spin coating method, blade coating method, dip coating method, casting method, roll coating method, bar coating method, die coating method and other coating methods, printing and ink jet patterning methods, etc. Can be used depending on the material.

[0048] The wet process includes a method of applying and drying a liquid in which fine particles of inorganic oxide are dispersed in an arbitrary organic solvent or water using a dispersion aid such as a surfactant as necessary, or an oxide precursor. A so-called sol-gel method in which a solution of a body, for example, an alkoxide body is applied and dried is used.

[0049] Of these, the atmospheric pressure plasma method and the sol-gel method are preferable.

[0050] A method for forming an insulating film by plasma film formation under atmospheric pressure is a process in which discharge is performed under atmospheric pressure or a pressure near atmospheric pressure, and a reactive gas is plasma-excited to form a thin film on a substrate. Therefore, the method is described in Japanese Patent Laid-Open Nos. 11-61406, 11-133205, 2000-121804, 2000-147209, 2000-185362, etc. And Thereby, a highly functional thin film can be formed with high productivity.

[0051] Further, as the organic compound film, polyimide, polyamide, polyester, polyacrylate, photo-radical polymerization system, photopower thione polymerization system photocurable resin, or copolymer containing acrylonitrile component, polybule Phenolic alcohol, polybutyl alcohol, novolac resin, cyano ethyl pullulan, and the like can also be used.

[0052] The wet process is preferable as a method of forming the organic compound film.

[0053] The inorganic oxide film and the organic oxide film can be laminated and used together. The thickness of these insulating films is generally 50 nm to 3 μm, preferably 100 nm to 1 μm.

[0054] The support is made of glass or a flexible resin sheet. For example, a plastic film can be used as the sheet. Examples of the plastic film include For example, polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyethersulfone (PES), polyetherimide, polyetheretherketone, polyphenylene sulfide, polyarylate, polyimide, polycarbonate (PC), cellulose triacetate (TAC), cellulose acetate propionate (CAP) and the like. In this way, by using a plastic film, it is possible to achieve lighter weight than when a glass substrate is used, to improve portability, and to improve resistance to impact.

Hereinafter, a field effect type organic thin film transistor using an organic thin film made of an organic semiconductor material of the present invention will be described.

FIG. 1 shows a configuration example of a field effect type organic thin film transistor using the organic semiconductor material of the present invention for an active layer. In FIG. 2 (a), a source electrode 2 and a drain electrode 3 are formed on a support 6 with a metal foil or the like, an active layer 1 made of the organic semiconductor material of the present invention is formed between both electrodes, and insulation is formed thereon. The field effect transistor is formed by forming the layer 5 and further forming the gate electrode 4 thereon. FIG. 2B shows the active layer 1 formed between the electrodes in FIG. 1A, which is formed so as to cover the entire surface of the electrode and the support using a coating method or the like. (C) shows that the active layer 1 is first formed on the support 6 using a coating method or the like, and then the source electrode 2, the drain electrode 3, the insulating layer 5, and the gate electrode 4 are formed.

In FIG. 4D, after forming the gate electrode 4 with a metal foil or the like on the support 6, the insulating layer 5 is formed, and the source electrode 2 and the drain electrode 3 are formed with the metal foil or the like thereon. Then, the active layer 1 made of the semiconductor material of the present invention is formed between the electrodes. Other configurations such as those shown in (e) and (f) of FIG.

Example

[0058] Hereinafter, the present invention will be described by way of examples, but the embodiments of the present invention are not limited thereto.

[0059] Example 1

A 2000 A thick thermal oxide film was formed on a Si wafer having a specific resistance of 0.01 Ω'cm as a gate electrode to form a gate insulating layer, and then surface treatment with octyltrichlorosilane was performed. Comparative compound <1> (poly (3-hexylthiophene) (regioregular, manufactured by Aldrich) (Appropriate molecular weight 89000, PHT)) was applied with an applicator and dried to form a cast film (thickness 50 nm), which was then heat-treated at 50 ° C for 30 minutes in a nitrogen atmosphere. Was given. Further, gold was deposited on the surface of this film using a mask to form source and drain electrodes. An organic thin film transistor element 1 having a source and drain electrode width of 100 m, a thickness of 200 nm, a channel width W = 3 mm, and a channel length L = 20 μm was fabricated.

[0060] The organic thin film transistor element 2 was prepared in the same manner as the organic thin film transistor element 1, except that the comparative compound <1> was replaced with the comparative compound <2> (pentacene, which was obtained by sublimation purification using a commercially available reagent manufactured by Aldrich). Was made.

[0061] [Chemical 6] Comparative compound <1> Comparative compound <2>

[0062] Organic thin film transistor elements 3 to 8 were produced in the same manner as in organic thin film transistor element 1, except that comparative compound <1> was replaced with the exemplary compounds according to the present invention shown in Table 1.

[0063] The organic thin film transistor elements 1 and 3 to 8 produced as described above exhibited good operating characteristics of p-channel enhancement type FETs. Furthermore, for the organic thin film transistor elements 1 to 8, the carrier mobility and the ONZOFF ratio (the ratio of the drain current when the gate bias is 50V and 0V with the drain bias of 50V) were obtained from the saturation region of the IV characteristics. The obtained device was left in the atmosphere for 1 month, and the carrier mobility and ONZOFF ratio were obtained again. The results are shown in Table 1.

[0064] [Table 1]

From the results in Table 1, it was found that the organic thin film transistor element of the present invention has good characteristics as a transistor and further suppresses deterioration over time. Further, the result of the organic thin film transistor element 2 using the comparative compound <2> (pentacene) clearly shows that it is difficult to obtain a pentacene thin film functioning as an active layer by forming a thin film by coating. The organic thin-film transistor device showed excellent characteristics as a transistor by forming a thin film by coating.

Claims

An organic semiconductor material comprising a compound represented by the following general formula (1):

[Chemical 1]

(Wherein, X to X each represents a substituent, and R to R represent a hydrogen atom or a substituent, respectively.

1 4 1 8

1

At least one of -R is not a hydrogen atom and is a substituent. )

8

[2] The organic semiconductor material according to claim 1, wherein the general formula (1) is represented by the following general formula (2).

[Chemical formula 2] General formula (2)

1 8 1 8

Represents. nl to n4 each represents an integer of 0 to 4. )

In the general formula (1), nl to n4 are all 0, and R, R, R, and R are each alkyl. And R, R, R, and R are each a hydrogen atom.

2 3 6 7

The organic semiconductor material according to item 1.

[4] In the general formula (1), nl to n4 are all 0, and one of R and R is an alkyl group and the other

1 8

One of R and R is an alkyl group and the other is a hydrogen atom.

4 5

The organic semiconductor material according to claim 1, wherein

[5] The organic semiconductor material according to claim 2, wherein in the general formula (2), nl to n4 are all 0.

[6] In the general formula (2), X, X, X, and X are each an alkyl group,

5 6 7 8

6. An organic semiconductor material according to claim 2 or claim 5.

[7] In the general formula (2), one of X and X is an alkyl group and the other is a hydrogen atom;

5 6 7

X is an alkyl group and the other is a hydrogen atom.

8

Item 6. The organic semiconductor material according to Item 5 or Item 5.

[8] In the general formula (2)! /, R, R, R, R are each an alkyl group, and R, R, R,

1 4 5 8 2 3 6

Each of R's is a hydrogen atom.

7

V, the organic semiconductor material according to item 1.

[9] In the general formula (2), one of R and R is an alkyl group and the other is a hydrogen atom;

1 8 4

Wherein one of R is an alkyl group and the other is a hydrogen atom.

Five

Item 8. The organic semiconductor material according to any one of Items 5 to 7.

[10] An organic semiconductor film comprising the organic semiconductor material according to any one of [1] to [9].

[11] An organic semiconductor element comprising the organic semiconductor material according to any one of claims 1 to 9.

[12] An organic thin film transistor comprising the organic semiconductor material according to any one of claims 1 to 9 in a semiconductor layer.

[13] A field-effect transistor comprising the organic semiconductor material according to any one of claims 1 to 9 in a semiconductor layer.

[14] A switching element using the organic thin film transistor according to claim 12 or the field effect transistor according to claim 13.