JP2007081288A - Organic semiconductor material, organic semiconductor film, organic semiconductor device and organic thin-film transistor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an organic semiconductor material which can be manufactured in a simple process, has good characteristics as a transistor, is stable to oxygen in the air and has sufficiently suppressed secular change, and to provide an organic semiconductor film employing the same, an organic semiconductor device and organic thin-film transistor. <P>SOLUTION: The organic semiconductor material contains a compound represented by a general formula (1): A-(L<SB>1</SB>-Q<SB>1</SB>)<SB>m</SB>. In the formula, A denotes an acene structure in which three rings or more are condensed, L<SB>1</SB>denotes bivalent coupled group, Q<SB>1</SB>denotes a substituent having singlet oxygen quenching function, and m denotes an integer of 1-4. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an organic semiconductor material, an organic semiconductor film, an organic semiconductor device, and an organic thin film transistor.

  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, information that has been provided in paper media has been increasingly digitized. As a mobile display medium that is thin, light, and portable, electronic paper or digital paper can be used. The need for is increasing.

  In general, in a flat panel display device, a display medium is formed using elements utilizing liquid crystal, organic EL (organic electroluminescence), electrophoresis, or the like. In such display media, a technique using an active drive element (TFT element) as an image drive element has become mainstream in order to ensure uniformity of screen brightness, screen rewrite speed, and the like. For example, in a normal 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 the TFT element, and these Si semiconductors (and metal films as necessary) are formed into a multilayer structure. The TFT element is manufactured by sequentially forming the drain and gate electrodes on the substrate. The manufacture of such a TFT element usually requires sputtering or other vacuum manufacturing processes.

  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, and the apparatus cost and running cost have become enormous. . For example, in a TFT element, it is usually necessary to repeat processes such as vacuum deposition, dope, photolithography, development, etc. many times to form each layer, and the element is formed on a substrate through tens of steps. Yes. As for the semiconductor portion that is the key to the switching operation, a plurality of types of semiconductor layers such as p-type and n-type are stacked. In such a conventional manufacturing method using a Si semiconductor, it is not easy to change the equipment, for example, a design change of a manufacturing apparatus such as a vacuum chamber is required in response to the need for a large display screen.

  In addition, since the formation of such a conventional TFT element using a Si material includes a process at a high temperature, the substrate material is restricted to be a material that can withstand the process temperature. Therefore, in practice, glass must be used, and when the above-described thin display such as electronic paper or digital paper is configured using such a conventionally known TFT element, the display is heavy and flexible. Products that may break due to chipping or dropping impact. These characteristics resulting from the formation of TFT elements on a glass substrate are undesirable in satisfying the need for an easy-to-carry-type thin display accompanying the progress of computerization.

  On the other hand, in recent years, organic semiconductor materials have been energetically studied as organic compounds having high charge transport properties. These compounds have been reported in many papers such as organic laser oscillation elements as discussed in Non-Patent Document 1, etc., and Non-Patent Document 2, for example, in addition to charge transport materials for organic EL elements. Application to organic thin film transistor elements (organic TFT elements) is expected. If these organic semiconductor devices can be realized, there is a possibility of obtaining a semiconductor that can be made into a solution by simplifying the manufacturing process by vacuum or low-pressure deposition at a relatively low temperature and further improving the molecular structure appropriately. It is conceivable that the organic semiconductor solution is made into an ink and manufactured 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 there is a possibility for devices using organic semiconductors, so the above-mentioned restrictions on substrate heat resistance are relaxed. For example, a TFT element may be formed on the 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 is lighter and more flexible than conventional ones, and will not crack even if dropped (or very difficult to break) It could be a display.

  However, organic semiconductors for realizing such TFT elements have been studied so far such as acenes such as pentacene and tetracene (for example, see Patent Document 1), phthalocyanines including lead phthalocyanine, perylene and its tetracarboxylic acid. Low molecular weight compounds such as acid derivatives (for example, see Patent Document 2), aromatic oligomers represented by thiophene hexamers called α-thienyl or sexithiophene (for example, see Patent Document 3), naphthalene, anthracene A compound in which a member aromatic heterocycle is condensed symmetrically (for example, see Patent Document 4), mono-, oligo- and polydithienopyridine (for example, see Patent Document 5), polythiophene, polythienylene vinylene, poly-p-phenylene Limited to conjugated polymers such as vinylene However, no material has been found that exhibits sufficient carrier mobility / ON / OFF ratio while maintaining sufficient solubility in a solvent. .

  Recently, it has been reported that a single crystal of rubrene, which is a highly soluble acene, has a very high mobility (see Non-Patent Document 4), but such a single crystal was produced by a vapor phase growth method. The film formed by solution casting is usually amorphous, and sufficient mobility is not obtained.

Further, a compound in which a functional group is added to pentacene, which is a compound having high carrier mobility by vacuum deposition, is disclosed, and it has been reported that relatively good carrier mobility can be obtained by solution coating. (For example, see Patent Document 6.)
However, acene-based compounds such as rubrene and pentacene are easily oxidized by oxygen contained in the air and converted into an oxidant called end peroxide, which may greatly deteriorate the performance as a field effect transistor. It is known that there are still problems to be solved regarding the storage stability in solution and the stability of the coating film.

  With respect to the stability over time of such an organic semiconductor element, for example, Japanese Patent Application Laid-Open No. 2003-292588, US Patent Application Publication Nos. 2003/136958, 2003/160230, and 2003/164495. "Using polymer TFTs as integrated circuit logic elements for microelectronics greatly improves their mechanical durability and extends their useful life. However, many of the semiconductor polythiophenes are oxidized by surrounding oxygen. It is considered unstable when exposed to air because it increases the conductivity and results in a large off-current for devices made from these materials, and thus a low current on / off ratio. Therefore, many of these materials eliminate environmental oxygen during material processing and device manufacturing. Care must be taken to avoid or minimize oxidative doping, as this precautionary measure increases manufacturing costs, and as an economical alternative to amorphous silicon technology, especially for large area devices. The attractiveness of certain polymer TFTs is diminished, and these and other disadvantages are avoided or minimized in embodiments of the present invention, thus having a strong resistance to oxygen and comparison As an electronic device that exhibits a high current ON / OFF ratio is desired, "the issue of how to prevent organic semiconductor materials from deteriorating over time is a major issue in commercialization. It has become an issue.

  As an example of an acene compound that is relatively stable against oxidation, in Non-Patent Documents 5 and 6, and Patent Document 7, some compounds in which the 6th and 13th positions of pentacene are substituted with silylethynyl groups are used. There are some reports that stability is good.

  However, these reports only describe qualitative properties in the text that stability against oxidation has been improved, and have not yet obtained stability enough to withstand practical use.

Further, in Non-Patent Document 7, by replacing part of the pentacene mother nucleus of a compound in which 6th and 13th positions of pentacene are substituted with a silylethynyl group with an electron withdrawing group such as a halogen atom or a cyano group, oxidation of the compound is performed. Although attempts have been made to increase the reduction potential, these compounds have a mobility of only 4.5 × 10 ⁻² cm ² / Vs at the maximum, and have both high mobility and device durability. Organic semiconductor materials have not been obtained yet.
JP-A-5-55568 Japanese Patent Laid-Open No. 5-190877 JP-A-8-264805 JP-A-11-195790 JP 2003-155289 A WO03 / 016599 US6690029B1 publication “Science” 289, 599 (2000) “Nature” 403, 521 (2000) Advanced Material, 2002, No. 2, page 99 Science, vol. 303 (2004), page 1644 Org. Lett. , Vol. 4 (2002), 15 pages J. et al. Am. Chem. Soc. , Vol. 127 (2005), 4986 pages Org. Lett. , Vol. 7 (2005), 3163 pages

  Accordingly, an object of the present invention is to provide an organic semiconductor material that is manufactured by a simple process, has good characteristics as a transistor, is stable against oxygen in the air, and sufficiently suppresses deterioration over time, and an organic material using the organic semiconductor material It is to provide a semiconductor film, an organic semiconductor device and an organic thin film transistor.

  Regarding the above problems, the inventors of the present invention first examined whether there is an additive that prevents the deterioration of the acene compound. As a result, it has been found that a singlet oxygen quencher, which is an additive for suppressing oxidative deterioration of conventional photographic materials, is effective.

  This is considered to be because acene compounds are oxidized and decomposed by singlet oxygen as described in Experimental Chemistry Course Vol. 17, pages 341 to 354.

  However, it was difficult to obtain a thin film with high crystallinity in a thin film coated with a solution containing these additives at a concentration having a sufficient effect, and an organic thin film having good semiconductor performance could not be obtained. .

  Therefore, the inventors of the present invention can obtain an organic thin film having stability against oxidation and good semiconductor properties by binding a substituent having a singlet oxygen quenching function via a linking group to an acene compound. As a result, the present invention has been completed.

  That is, the said subject of this invention is achieved by the following structures.

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

Formula _{(1) A- (L 1 -Q} 1) m
In the formula, A represents an acene structure in which three or more rings are condensed, L ₁ represents a divalent linking group, Q ₁ represents a substituent having a singlet oxygen quenching function, and m represents an integer of 1 to 4. To express.

(2) The organic semiconductor material as described in (1) above, which is a compound represented by the general formula (1), wherein the linking group L ₁ is a group containing an ethynyl group.

  (3) The organic semiconductor material according to (1) or (2), wherein the compound represented by the general formula (1) is a compound represented by the following general formula (2).

In the formula, L ₂ represents a divalent linking group, Q ₂ represents a substituent having a singlet oxygen quenching function, and Z represents a substituted or unsubstituted aromatic ring.

  (4) The organic semiconductor material according to any one of (1) to (3), wherein the substituent having the singlet oxygen quenching function is a cyclic amine structure.

  (5) An organic semiconductor material comprising a compound represented by the following general formula (3).

In the formula, L ₃ represents a linking group selected from a substituted or unsubstituted carbon atom, a nitrogen atom, an oxygen atom, a sulfur atom, and a single bond, and R _{1 to} R ₈ are a hydrogen atom, a halogen atom, or a substituted or unsubstituted group. It represents a substituted alkyl group and may be linked to each other. Z represents a substituted or unsubstituted aromatic ring.

  (6) The compound represented by the general formula (2) or (3), wherein the aromatic ring represented by Z is an unsubstituted benzene ring. The organic semiconductor material according to any one of (1).

  (7) An organic semiconductor film comprising the organic semiconductor material according to any one of (1) to (6).

  (8) It is formed by dissolving the organic semiconductor material according to any one of (1) to (6) in an organic solvent, and applying and drying the obtained solution ( The organic semiconductor film as described in 7).

  (9) An organic semiconductor device using the organic semiconductor material according to any one of (1) to (6).

  (10) An organic thin film transistor using the organic semiconductor material according to any one of (1) to (6) for a semiconductor layer.

  According to the present invention, there are provided an organic semiconductor material that is manufactured by a simple process, has good characteristics as a transistor, and further suppresses deterioration over time, and an organic semiconductor film, an organic semiconductor device, and an organic thin film transistor using the organic semiconductor material. be able to.

  In the organic semiconductor material of the present invention, an organic semiconductor material useful for thin film transistor applications can be obtained by using a compound having a structure defined in any one of claims 1 to 5. In addition, the organic semiconductor film, organic semiconductor device, and organic thin film transistor (hereinafter also referred to as organic TFT) of the present invention produced using the organic semiconductor material have high carrier mobility and good ON / OFF characteristics. It was found that the transistor had excellent transistor characteristics and high durability.

  Hereinafter, details of each component according to the present invention will be described.

[Organic semiconductor materials]
The organic semiconductor material of the present invention is an organic semiconductor material having a structure in which an acene mother nucleus is bonded to a substituent having a singlet oxygen quenching function by a linking group, as represented by the following general formula (1). Features.

Formula _{(1) A- (L 1 -Q} 1) m
In the formula, A represents an acene structure in which three or more rings are condensed, L ₁ represents a divalent linking group, Q ₁ represents a substituent having a singlet oxygen quenching function, and m represents an integer of 1 to 4. To express.

The substituent having a singlet oxygen quenching function represented by Q ₁ can be used without limitation as long as it is a functional group that can deactivate singlet oxygen in an excited state.

  As a mechanism for quenching singlet oxygen, there are a chemical quenching mechanism and a physical quenching mechanism, and a functional group having either mechanism can be used. The chemical quenching mechanism is a mechanism that consumes singlet oxygen through chemical reaction with singlet oxygen, and the physical quenching mechanism is a mechanism of singlet oxygen and electron such as a transition metal element. This is a mechanism for deactivating singlet oxygen in an excited state to triplet oxygen in a ground state by exchanging spins.

  As a method of evaluating the quenching function of these singlet oxygen quenchers, the method described in the 22nd Oxidation Reaction Discussion Summary p7 is known. The singlet oxygen quenching rate (kq) is determined by the above method. However, since the chemical quenching mechanism and the physical quenching mechanism cannot be measured separately, only the sum of them can be evaluated.

In the present invention, the singlet oxygen quenching rate obtained by the above method (kq) is 10 ⁵ or more compounds, it is preferable to use a substituent Q ₁ which is obtained by removing one substituent or a hydrogen atom at any position . In view of the stability of these substituents, it is preferably 10 ⁹ or less.

The substituent Q ₁ having such characteristics is a substituent having a structure similar to that of the compounds represented by compounds SQ1 to SQ9 described in JP-A-11-288066, pages 37 to 39. preferable. That is, it is a substituent having the following structure as a partial structure.

  In addition to the above structure, nickel dimethyldithiocarbamate, nickel 3,5-di-t-butyl-4-hydroxybenzyl O-ethylphosphonate, nickel 3,5-di-t-butyl-4-hydroxybenzyl O-butylphosphonate, nickel [2,2′-thiobis (4-t-octylphenolate)] (n-butylamine), nickel [2,2′-thiobis (4-t-octylphenolate)] (2-ethylhexylamine), nickel bis [2,2′-thio-bis (4-t-octylphenolate)], nickel bis [2,2′-sulfone-bis (4-octylphenolate)], nickel Bis (2-hydroxy-5-methoxyphenyl-Nn-butylaldoimine), nickel bis (dithiobenzyl), nickel bis (di Since transition metal compounds such as obiacetyl) are known as good singlet oxygen quenchers, transition metals, especially substituents having group 8-11 transition metal atoms, are also substituents having a singlet oxygen quenching function. Useful. These substituents may have various substituents described later.

Further, the acene mother nucleus A that is bonded to the substituent Q ₁ having a singlet oxygen quenching function through the linking group L ₁ needs to be an acene mother nucleus in which three or more rings are condensed. . This is because a condensed ring mother nucleus having less than 3 rings has insufficient mobility as a semiconductor. On the other hand, the greater the number of condensed rings, the easier it is to oxidize against singlet oxygen. Therefore, the number of condensed rings in the acene-based mother nucleus is preferably 7 or less. More preferred is an acene-based compound in which four to five rings are condensed, and still more preferred is an acene-based compound in which five rings having high molecular symmetry and good crystallinity are condensed.

  Examples of such acene-based mother nucleus A include anthracene, acridine, benzoquinoline, carbazole, phenazine, phenanthridine, diazacarbazole, dibenzofuran, dibenzothiophene, naphthofuran, naphththiophene, benzodifuran, benzodithiophene, tetracene, Naphthoindole, anthrafuran, anthrathiophene, naphthoquinoline, naphthoisoquinoline, naphthoquinoxaline, naphthophthalazine, naphthoquinazoline, pentacene, pyrrolonaphthacene, thienonaphthacene, anthradifuran, anthradithiophene, 1-azapentacene, 1,8-diazapentacene, 2 , 9-diazapentacene, hexacene, dibenzopentacene, hexacene, dithienopentacene, heptacene and the like. These acene-based nuclei may have a substituent as described later.

The linking group L ₁ that connects the substituent Q ₁ having a singlet oxygen quenching function and the acene mother nucleus A can be used without limitation as long as it is a divalent linking group.

Examples of the linking group L ₁ include alkylene groups such as methylene group, ethylene group and hexamethylene group, alkenylene groups such as vinylene group and 1,2-dichloroethylene group, alkynylene groups such as ethynyl group, cyclohexane-1,4- Examples include cycloalkylene groups such as diyl groups, arylene groups such as phenylene groups, ether groups, amino groups, thioether groups, carbonyl groups, thiocarbonyl groups, carbonylimino groups, sulfoxide groups, sulfone groups, single bonds, and the like. A plurality of these may be bonded in series to form one linking group, or may be introduced as a substituent in which a part of the hydrogen atoms of the linking group are replaced, and may have a branched structure. Moreover, you may have a substituent as mentioned later.

Examples of the substituent that can replace the substituent Q ₁ having the singlet oxygen quenching function, the acene-based nucleus A, and the linking group L ₁ include the following substituents.

Alkyl group: for example, methyl group, ethyl group, propyl group, isopropyl group, tert-butyl group, neopentyl group, hexyl group, octyl group, decyl group, dodecyl group, tetradecyl group, pentadecyl group, etc.
A cycloalkyl group: for example, a cyclopentyl group, a cyclohexyl group, etc.
Alkenyl group: For example, vinyl group, allyl group, 1,2-dichloroethylene group, etc.
Alkynyl group: ethynyl group, propargyl group, diethynyl group, etc.
Aryl group (also called aromatic carbocyclic group, aromatic hydrocarbon group, etc.): for example, phenyl group, p-chlorophenyl group, tolyl group, xylyl group, mesityl group, biphenylyl group, etc.
Also naphthalene ring, anthracene ring, azulene ring, acenaphthene ring, fluorene ring, phenanthrene ring, indene ring, pyrene ring, tetracene ring, pentacene ring, hexacene ring, benzopyrene ring, benzoazulene ring, chrysene ring, benzochrysene ring, acenaphthene ring, Acenaphthylene ring, triphenylene ring, coronene ring, benzocoronene ring, hexabenzocoronene ring, benzofluorene ring, fluoranthene ring, perylene ring, naphthoperylene ring, pentabenzoperylene ring, benzoperylene ring, pentaphen ring, picene ring, pyranthrene ring, coronene ring , A substituent in which a part of hydrogen of a condensed aromatic hydrocarbon ring such as a naphtho-colonene ring, an ovarene ring or an anthraanthrene ring is replaced, etc.
Heteroaryl group (also called aromatic heterocyclic group): for example, pyridine ring, pyridazine ring, pyrimidine ring, pyrazine ring, triazine ring, tetrazine ring, quinoline ring, isoquinoline ring, acridine ring, phenanthridine ring, quinoxaline ring, Cinnoline ring, phthalazine ring, quinazoline ring, naphthyridine ring, pteridine ring, phenazine ring, phenanthroline ring, pyrrole ring, pyrazole ring, imidazole ring, triazole ring, indole ring, benzimidazole ring, carbazole ring, purine ring, pyrrolopyrrole ring, Pyrazolotriazole ring, benzoquinoline ring, carbazole ring, azacarbazole ring, phenazine ring, phenanthridine ring, phenanthroline ring, carboline ring, cyclazine ring, kindrin ring, tepenidine ring, quinindrin ring, trif Nodithiazine ring, triphenodioxazine ring, phenanthrazine ring, anthrazine ring, perimidine ring, diazacarbazole ring (representing any one of carbon atoms constituting a carboline ring replaced by a nitrogen atom), phenanthroline ring, furan Ring, benzofuran ring, isobenzofuran ring, dibenzofuran ring, oxazole ring, isoxazole ring, oxadiazole ring, furazane ring, thiophene ring, benzothiophene ring, thieno [2,3-a] thiophene ring, thieno [2,3 -B] part of hydrogen of a condensed aromatic hydrocarbon ring such as a thiophene ring, anthradithiophene ring, dithiafulvene ring, thiazole ring, benzothiazole ring, dibenzothiophene ring, benzodithiophene ring, anthradithiophene ring, thiothiophene ring Substituent etc. that replaced
Heterocyclic group: epoxy ring, aziridine ring, thiirane ring, oxetane ring, azetidine ring, thietane ring, tetrahydrofuran ring, dioxolane ring, pyrrolidine ring, pyrazolidine ring, imidazolidine ring, oxazolidine ring, tetrahydrothiophene ring, sulfolane ring, thiazolidine ring , Ε-caprolactone ring, ε-caprolactam ring, piperidine ring, hexahydropyridazine ring, hexahydropyrimidine ring, piperazine ring, morpholine ring, tetrahydropyran ring, 1,3-dioxane ring, 1,4-dioxane ring, trioxane ring Tetrahydrothiopyran ring, thiomorpholine ring, thiomorpholine-1,1-dioxide ring, pyranose ring, diazabicyclo [2,2,2] -octane ring,
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: for example, phenoxy group, naphthyloxy group, etc.
Alkylthio group: for example, methylthio group, ethylthio group, propylthio group, pentylthio group, hexylthio group, octylthio group, dodecylthio group, etc.
Cycloalkylthio group: for example, cyclopentylthio group, cyclohexylthio group, etc.
Arylthio group: for example, phenylthio group, naphthylthio group, etc.
Alkoxycarbonyl group: For example, methyloxycarbonyl group, ethyloxycarbonyl group, butyloxycarbonyl group, octyloxycarbonyl group, dodecyloxycarbonyl group, etc.
Aryloxycarbonyl group: for example, phenyloxycarbonyl group, naphthyloxycarbonyl group, etc.
Sulfamoyl group: for example, aminosulfonyl group, methylaminosulfonyl group, dimethylaminosulfonyl group, butylaminosulfonyl group, hexylaminosulfonyl group, cyclohexylaminosulfonyl group, octylaminosulfonyl group, dodecylaminosulfonyl group, phenylaminosulfonyl group, naphthyl An aminosulfonyl group, a 2-pyridylaminosulfonyl group, etc.
Acyl group: For example, acetyl group, ethylcarbonyl group, propylcarbonyl group, pentylcarbonyl group, cyclohexylcarbonyl group, octylcarbonyl group, 2-ethylhexylcarbonyl group, dodecylcarbonyl group, phenylcarbonyl group, naphthylcarbonyl group, pyridylcarbonyl group, etc. ,
Acyloxy group: For example, acetyloxy group, ethylcarbonyloxy group, butylcarbonyloxy group, octylcarbonyloxy group, dodecylcarbonyloxy group, phenylcarbonyloxy group, etc.
Amide group: For example, methylcarbonylamino group, ethylcarbonylamino group, dimethylcarbonylamino group, propylcarbonylamino group, pentylcarbonylamino group, cyclohexylcarbonylamino group, 2-ethylhexylcarbonylamino group, octylcarbonylamino group, dodecylcarbonylamino group Group, phenylcarbonylamino group, naphthylcarbonylamino group, etc.
Carbamoyl group: For example, aminocarbonyl group, methylaminocarbonyl group, dimethylaminocarbonyl group, propylaminocarbonyl group, pentylaminocarbonyl group, cyclohexylaminocarbonyl group, octylaminocarbonyl group, 2-ethylhexylaminocarbonyl group, dodecylaminocarbonyl group , Phenylaminocarbonyl group, naphthylaminocarbonyl group, 2-pyridylaminocarbonyl group, etc.
Ureido group: For example, methylureido group, ethylureido group, pentylureido group, cyclohexylureido group, octylureido group, dodecylureido group, phenylureido group, naphthylureido group, 2-pyridylaminoureido group, etc.
Amino group: For example, amino group, ethylamino group, dimethylamino group, butylamino group, cyclopentylamino group, 2-ethylhexylamino group, dodecylamino group, anilino group, naphthylamino group, 2-pyridylamino group, etc.
Halogen atom: For example, fluorine atom, chlorine atom, bromine atom, etc.
Fluorinated hydrocarbon group: For example, fluoromethyl group, trifluoromethyl group, pentafluoroethyl group, pentafluorophenyl group, etc.
Silyl group: For example, trimethylsilyl group, triisopropylsilyl group, triphenylsilyl group, phenyldiethylsilyl group, trimethoxysilyl group, triethoxysilyl group, silatrane group,
Sulfinyl group: For example, methylsulfinyl group, ethylsulfinyl group, butylsulfinyl group, cyclohexylsulfinyl group, 2-ethylhexylsulfinyl group, dodecylsulfinyl group, phenylsulfinyl group, naphthylsulfinyl group, 2-pyridylsulfinyl group, etc.
Sulfonyl group: For example, methylsulfonyl group, ethylsulfonyl group, butylsulfonyl group, cyclohexylsulfonyl group, 2-ethylhexylsulfonyl group, dodecylsulfonyl group, etc., phenylsulfonyl group, naphthylsulfonyl group, 2-pyridylsulfonyl group, etc.
Other substituents: cyano group, nitro group, hydroxy group, mercapto group, alkylsilyl group, disulfide group, sulfoxide group, sulfone group, sulfoximine group, oxo group (= O), thione group (= S), phosphate ester Group, thiophosphate group, phosphorylamino group, phosphite group, etc.
Is mentioned. These substituents may be further substituted with the above substituents. In addition, a plurality of these substituents may be bonded to each other to form a ring.

Of the structure represented by the general formula (1), a compound wherein L ₁ is an ethynyl group is preferable.

  It is known that the conductivity of an organic semiconductor is mainly transmitted in a direction perpendicular to the plane of the acene host nucleus, and as the overlap between the acene host nuclei increases, better semiconductor characteristics can be obtained.

The substituent Q ₁ having a singlet oxygen quenching function connected to the acene mother nucleus is a relatively large substituent, and when present in the vicinity of the acene mother nucleus, the stack of the acene mother nuclei is inhibited, and the semiconductor characteristics because it can reduce the substituents Q ₁ having a singlet oxygen quencher function, it is preferably present at a position apart so as not to inhibit the stack between acene nucleus.

Therefore, the linking group L ₁ is preferably an ethynyl group. Unlike an alkylene group, an alkenylene group, etc., an ethynyl group is a straight linking group and has the same thickness as the acene mother nucleus, and therefore does not inhibit the stack of the acene mother nucleus.

  In addition, the ethynyl group is a relatively electron-withdrawing substituent, and has an effect of reducing the oxidation-reduction potential of the acene-based mother nucleus and preventing oxidative degradation.

  Furthermore, since the ethynyl group has a rigid structure, the crystallinity of the compound is increased. As a result, the arrangement of the compound in the coating film is aligned, and a thin film with higher mobility can be obtained. In addition, there is an effect that deterioration factors such as oxygen and moisture are less likely to penetrate into the thin film, and deterioration is less likely to occur.

  In order to further improve the crystallinity of the compound, it is preferable that the compound not only has a rigid structure but also has a high symmetry. Further, the larger the number of condensed rings in the acene-based mother nucleus, the higher the crystallinity. However, as described above, since a large condensed ring structure is easily oxidized, the number of condensed rings in the acene-based mother nucleus may be five. preferable.

Further, the linking group L ₁ can have a highly symmetric structure by substituting the peri position at the center of the acene-based mother nucleus. That is, a structure represented by the following general formula (2) is preferable.

In the formula, Q ₂ represents a substituent having a singlet oxygen quenching function, and Z represents a substituted or unsubstituted aromatic ring. L ₂ represents a divalent linking group, and similarly to the linking group L ₁ , a substituted or unsubstituted alkylene group, alkenylene group, alkynylene group, cycloalkylene group, arylene group, ether group, amino group, thioether group, carbonyl Represents a group, a thiocarbonyl group, a carbonylimino group, a sulfoxide group, a sulfone group, a single bond and the like.

  By setting it as such a structure, a point symmetrical structure or a line symmetrical structure can be provided, and a coating film with higher crystallinity can be obtained.

The substituents Q ₁ and Q ₂ having a singlet oxygen quenching function are preferably substituents having a cyclic amine structure. When comparing kq of SQ1 to SQ9 described on pages 37 to 39 of JP-A-11-288066, all three structures having the highest kq (SQ5 to SQ7) have a cyclic amine structure. This is because these structures are one of the functional groups having the highest singlet oxygen quenching function.

  More preferred is a compound having a structure represented by the following general formula (3).

In the formula, R _{1 to} R ₈ represent a hydrogen atom, a halogen atom, or a substituted or unsubstituted alkyl group, and may be connected to each other. Z represents a substituted or unsubstituted aromatic ring. L ₃ represents a linking group selected from a substituted or unsubstituted carbon atom, a nitrogen atom, an oxygen atom, a sulfur atom, and a single bond.

  As shown in the general formula (3), when the atom bonded to the ethynyl group is a nitrogen atom, the structure becomes similar to a quinoid structure in which oxidation and reduction are reversible as described below, and the stability against oxidation is further improved. Estimated.

  Among them, a compound in which the aromatic ring represented by Z is an unsubstituted benzene ring and the acene mother nucleus is pentacene is preferable. By adopting such a structure, the compound has high symmetry and excellent crystallinity, and the coating film of these compounds can achieve both excellent mobility and oxidation stability.

  The molecular weight of the compounds represented by the general formulas (1) to (3) is preferably in the range of 300 to 5000. By setting the molecular weight to 300 or more, the volatility of the compound can be sufficiently lowered, and volatilization and process contamination during production can be prevented. Moreover, the solubility to a solvent can be kept in a favorable range by setting it as 5000 or less. Moreover, the stacking property between molecules can be made good, and the TFT performance can be made good. The molecular weight is more preferably in the range of 500 to 2000. The molecular weight of the organic semiconductor material of the present invention can be measured with a mass spectrometer or the like.

  Hereinafter, although the specific example of a compound represented by General formula (1)-(3) based on this invention is shown, this invention is not limited to these.

The above compounds can be synthesized with reference to the following documents.
Ethynylbenzene compounds: see, for example, Helv. Chim. Acta. , Vol. 86 (2003), p 2754-2759, etc. Ethinyl ether compounds: see, for example, Synthesis, vol. 4 (1994), p432, etc. Ethynyl heterocyclic compounds: Am. Chem. Soc. , Vol. 124 (2002), p2456, supporting information, etc., metal acetylide compounds: Am. Chem. Soc. , Vol. 119 (1997), p7992 (Ni complex), Inorganica Chimica Acta, vol. 358 (2005), p1429 (Au complex), etc./Addition reaction to acene nucleus: For example, Non-Patent Document 6, J. Am. Am. Chem. Soc. , Vol. 123 (2001), p9482, supporting information
[Organic semiconductor film, organic semiconductor device, organic thin film transistor]
The organic semiconductor film, organic semiconductor device, and organic thin film transistor of the present invention will be described.

  When the organic semiconductor material of the present invention is used for a semiconductor layer of an organic semiconductor film, an organic semiconductor device, or an organic thin film transistor, an organic semiconductor device and an organic thin film transistor that are driven well can be provided. An organic thin film transistor has a top gate type having a source electrode and a drain electrode connected with an organic semiconductor as a semiconductor layer on a support, and having a gate electrode on the support via a gate insulating layer. It is roughly classified into a bottom gate type having a gate electrode and having a source electrode and a drain electrode connected by an organic semiconductor through a gate insulating layer.

  In order to install the organic semiconductor material of the present invention on a semiconductor layer of an organic semiconductor film, an organic semiconductor device, or an organic thin film transistor, it can be installed on a substrate by vacuum deposition, but it can be dissolved in an appropriate solvent and added as necessary. It is preferable to place the solution prepared by adding the solution on the substrate by cast coating, spin coating, printing, inkjet method, ablation 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 the organic semiconductor material can be dissolved to prepare a solution having an appropriate concentration, but specifically, diethyl ether or diisopropyl ether. Linear ether solvents such as tetrahydrofuran and dioxane, ketone solvents such as acetone and methyl ethyl ketone, alkyl halide solvents such as chloroform and 1,2-dichloroethane, toluene, o-dichlorobenzene, nitrobenzene And aromatic solvents such as m-cresol, N-methylpyrrolidone, carbon disulfide and the like. Of these solvents, a solvent containing a non-halogen solvent is preferable, and a non-halogen solvent is preferable.

  In the organic thin film transistor of the present invention, the organic semiconductor material of the present invention is preferably used for the semiconductor layer as described above. The semiconductor layer is preferably formed by applying a solution or dispersion containing these organic semiconductor materials. The solvent for dissolving the organic semiconductor material is preferably a solvent containing the non-halogen solvent, and is preferably composed of a non-halogen solvent.

  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, antimony lead, tantalum, indium , Palladium, tellurium, rhenium, iridium, aluminum, ruthenium, germanium, molybdenum, tungsten, tin oxide / antimony, indium tin oxide (ITO), fluorine doped zinc oxide, zinc, carbon, graphite, glassy carbon, silver paste and carbon Paste, lithium, beryllium, sodium, magnesium, potassium, calcium, scandium, titanium, manganese, zirconium, gallium, niobium, sodium, sodium-potassium alloy, magnesium, lithium, aluminum, magnesium / Copper mixture, magnesium / silver mixture, magnesium / aluminum mixture, magnesium / indium mixture, aluminum / aluminum oxide mixture, lithium / aluminum mixture, etc., especially platinum, gold, silver, copper, aluminum, indium, ITO And carbon are preferred. Alternatively, a known conductive polymer whose conductivity is improved by doping or the like, for example, conductive polyaniline, conductive polypyrrole, conductive polythiophene, a complex of polyethylenedioxythiophene and polystyrenesulfonic acid, or the like is also preferably used. Among them, those having low electrical resistance at the contact surface with the semiconductor layer are preferable.

  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, or a metal foil such as aluminum or copper There is a method of etching using a resist by thermal transfer, ink jet or the like. Alternatively, a conductive polymer solution or dispersion, or a conductive fine particle dispersion may be directly patterned by ink jetting, or may be formed from a coating film by lithography, laser ablation, or the like. 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 a relief printing plate, an intaglio printing plate, a planographic printing plate or a screen printing can be used.

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

  Examples of the method for forming the film include a vacuum process, a molecular beam epitaxial growth method, an ion cluster beam method, a low energy ion beam method, an ion plating method, a CVD method, a sputtering method, an atmospheric pressure plasma method, and the like, spraying Examples include a wet process such as a coating method, a spin coating method, a blade coating method, a dip coating method, a casting method, a roll coating method, a bar coating method, a coating method such as a die coating method, and a patterning method such as printing or inkjet. Can be used depending on the material.

  The wet process is 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 required, or an oxide precursor, for example, A so-called sol-gel method in which a solution of an alkoxide body is applied and dried is used. Among these, the atmospheric pressure plasma method and the sol-gel method are preferable.

  The method for forming an insulating film by plasma film formation under atmospheric pressure is a process in which a reactive gas is discharged under atmospheric pressure or a pressure near atmospheric pressure to excite reactive gas to form a thin film on a substrate. The method is described in JP-A-11-61406, JP-A-11-133205, JP-A-2000-121804, JP-A-2000-147209, JP-A-2000-185362 (hereinafter referred to as atmospheric pressure). Also called plasma method). Accordingly, a highly functional thin film can be formed with high productivity.

  In addition, as an organic compound film, polyimide, polyamide, polyester, polyacrylate, photo-curing polymer of photo radical polymerization system, photo cation polymerization system, or copolymer containing acrylonitrile component, polyvinyl phenol, polyvinyl alcohol, novolac resin, and Cyanoethyl pullulan or the like can also be used. As the method for forming the organic compound film, the wet process is preferable. An inorganic oxide film and an 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.

  Moreover, a support body is comprised with glass or a flexible resin-made sheet | seat, for example, a plastic film can be used as a sheet | seat. Examples of the plastic film include polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyethersulfone (PES), polyetherimide, polyetheretherketone, polyphenylene sulfide, polyarylate, polyimide, polycarbonate (PC). And a film made of triacetyl cellulose (TAC), diacetyl cellulose (DAC), cellulose acetate propionate (CAP), or the like. Thus, by using a plastic film, the weight can be reduced as compared with the case of using a glass substrate, the portability can be improved, and the resistance to impact can be improved.

  Below, the organic thin-film transistor using the organic-semiconductor film formed using the organic-semiconductor material of this invention is demonstrated.

  FIG. 1 is a diagram showing a configuration example of an organic thin film transistor of the present invention. In FIG. 2A, a source electrode 2 and a drain electrode 3 are formed on a support 6 by a metal foil or the like, an organic semiconductor layer 1 made of the organic semiconductor material of the present invention is formed between the two electrodes, and a substrate is formed thereon. An insulating layer 5 is formed, and a gate electrode 4 is further formed thereon to form an organic thin film transistor. FIG. 2B shows the organic semiconductor layer 1 formed between the electrodes in FIG. 1A so as to cover the entire surface of the electrode and the support using a coating method or the like. (C) shows that the organic semiconductor layer 1 is first formed on the support 6 by 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 on the support 6 with a metal foil or the like, the insulating layer 5 is formed, and the source electrode 2 and the drain electrode 3 are formed on the metal foil or the like on the insulating layer 5. An organic semiconductor layer 1 made of the organic semiconductor material of the present invention is formed between the electrodes. In addition, the configuration as shown in FIGS.

  FIG. 2 is a diagram showing an example of a schematic equivalent circuit diagram of an organic thin film transistor sheet.

  The organic thin film transistor sheet 10 has a large number of organic thin film transistors 11 arranged in a matrix. 7 is a gate bus line of each organic thin film transistor 11, and 8 is a source bus line of each organic thin film transistor 11. An output element 12 is connected to the source electrode of each organic thin film transistor 11, and this output 12 is, for example, a liquid crystal, an electrophoretic element or the like, and constitutes a pixel in the display device. The pixel electrode may be used as an input electrode of the photosensor. In the illustrated example, a liquid crystal as an output element is shown by an equivalent circuit composed of a resistor and a capacitor. 13 is a storage capacitor, 14 is a vertical drive circuit, and 15 is a horizontal drive circuit.

The performance of the organic thin film transistor, but is the performance changes needed depending on the application, for example, in applications such as electronic paper, the carrier mobility 0.01 (1.0 × 10 ^-2) ~1 It is preferably in the range of 0.0 cm ² / Vsec, and the ON / OFF ratio is preferably in the range of 1.0 × 10 ^{5 to} 1.0 × 10 ⁷ . By setting it as such a range, a display can be driven at sufficient speed and a favorable gradation can be provided to a display.

  EXAMPLES Hereinafter, although an Example is given and this invention is demonstrated in detail, this invention is not limited to these.

  Here, structural formulas of compounds used in Examples are shown.

Example 1
<< Production of Organic Thin Film Transistor 1 >>
A 200 nm 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 octadecyltrichlorosilane was performed.

  On a Si wafer subjected to such a surface treatment, Comparative Compound 1 (Pentacene, manufactured by Aldrich, used after sublimation purification of a commercially available reagent) was added to toluene that was bubbled with nitrogen for 30 minutes in a nitrogen atmosphere. , Dissolved at a concentration of 5% by mass, spin-coated under a nitrogen atmosphere (rotation speed: 2500 rpm, 15 seconds), naturally dried to form a cast film, and 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 a source electrode and a drain electrode. An organic thin film transistor 1 having a source electrode and a drain electrode having a width of 100 μm, a thickness of 200 nm, a channel width W = 3 mm, and a channel length L = 20 μm was produced.

<< Production of Organic Thin Film Transistor 2 >>
Comparative compound 2 (2,3,9,10-tetrahexylpentacene) is described in Organic Letters, vol. 2 (2000), p85.

  An organic thin film transistor 2 was produced in the same manner as in the production of the organic thin film transistor 1, except that the comparative compound 1 was changed to the comparative compound 2.

<< Production of Organic Thin Film Transistor 3 >>
In the production of the organic thin film transistor 1, the organic thin film transistor 3 was produced in the same manner except that the comparative compound 1 was changed to the comparative compound 3 (Lubrene, manufactured by Aldrich, used after sublimation purification of a commercially available reagent).

<< Production of Organic Thin Film Transistor 4 >>
Comparative compound 4 is described in J. Org. Am. Chem. Soc. , Vol. 123 (2001), p9482, supporting information.

  An organic thin film transistor 4 was produced in the same manner as in the production of the organic thin film transistor 1, except that the comparative compound 1 was changed to the comparative compound 4.

<< Production of Organic Thin Film Transistor 5 >>
Comparative compound 5 was synthesized by the method described in Non-Patent Document 6, supporting information.

  An organic thin film transistor 5 was produced in the same manner as in the production of the organic thin film transistor 1, except that the comparative compound 1 was changed to the comparative compound 5.

<< Production of Organic Thin Film Transistors 6-11 >>
In the production of the organic thin film transistor 1, organic thin film transistors 6 to 11 were produced in the same manner except that the organic semiconductor material of the present invention described in Table 1 was used instead of the comparative compound 1.

<< Evaluation of carrier mobility and ON / OFF value >>
About the obtained organic thin-film transistors 1-14, the carrier mobility and ON / OFF value of each element were measured immediately after element preparation. In the present invention, the carrier mobility is obtained from the saturation region of the IV characteristic, and the ON / OFF ratio is obtained from the ratio of the drain current values when the drain bias is −50 V and the gate bias is −50 V and 0 V. It was.

  Further, the same evaluation was carried out for 48 hours after each element was placed in an environmental chamber at 40 ° C. and 90% RH, and then the carrier mobility / ON / OFF ratio was measured again.

  The obtained results are shown in Table 1.

  From the results shown in Table 1, Comparative Compound 1 has low solubility, and a film cannot be formed by coating, and the organic semiconductor element 1 was not confirmed to be driven as a semiconductor.

Comparative compounds 2 and 3 have improved solubility compared to comparative compound 1 and can form a coating film, and organic semiconductor elements 2 and 3 were confirmed to be driven as semiconductors. It can be seen that the / OFF ratio is relatively low at 10 ³ units or less, and that the performance greatly deteriorates after the durability test.

The organic semiconductor elements 4 and 5 showed sufficient TFT performance immediately after coating film formation, but after the durability test, the mobility was 10 ⁻³ units and the ON / OFF ratio was 10 ⁴ units, and the display could be driven. The value is not retained.

On the other hand, the organic thin film transistors 6 to 11 manufactured using the organic semiconductor material of the present invention show excellent characteristics in both carrier mobility and ON / OFF ratio immediately after the manufacture, and the mobility is 10 ⁻ after the durability test. ^two or more, ON / OFF ratio is at even 10 ⁵ or more units, it can be seen that both the less high durability deterioration over time.

Among the organic semiconductor elements of the present invention, the organic TFT elements 9 and 10 using an acene compound substituted with ethynylpiperazine maintain a mobility of 10 ⁻¹ even after an endurance test. It was confirmed that the organic semiconductor element had durability.

Example 2
<< Production of organic EL element >>
The organic EL element was produced by referring to the method described in Nature, Vol. 395, pages 151 to 154, and producing a top emission type organic EL element having a sealing structure as shown in FIG. 3, 101 is a substrate, 102a is an anode, 102b is an organic EL layer (specifically, an electron transport layer, a light emitting layer, a hole transport layer, etc. are included), 102c is a cathode, and an anode 102a The light emitting element 102 is formed by the organic EL layer 102b and the cathode 102c. Reference numeral 103 denotes a sealing film. The organic EL element of the present invention may be either a bottom emission type or a top emission type.

  The organic EL element of the present invention and the organic thin film transistor of the present invention (herein, the organic thin film transistor of the present invention is used as a switching transistor, a driving transistor, etc.) were produced to produce an active matrix light emitting element. For example, as shown in FIG. 4, a mode in which a substrate in which a TFT 602 (or an organic thin film transistor 602 may be formed) is formed on a glass substrate 601 is used as an example. Here, a known TFT manufacturing method can be referred to for the TFT 602 manufacturing method. Of course, the TFT may be a conventionally known top gate TFT or bottom gate TFT.

  The organic EL device produced above showed good light emission characteristics in various light emission forms such as single color, full color, and white.

It is a figure which shows the structural example of the organic TFT which concerns on this invention. It is an example of the schematic equivalent circuit schematic of the organic TFT of this invention. It is a schematic diagram which shows an example of the organic EL element which has a sealing structure. It is a schematic diagram which shows an example of the board | substrate which has TFT used for an organic EL element.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Organic-semiconductor layer 2 Source electrode 3 Drain electrode 4 Gate electrode 5 Insulating layer 6 Support body 7 Gate bus line 8 Source bus line 10 Organic thin-film transistor sheet 11 Organic thin-film transistor 12 Output element 13 Storage capacitor 14 Vertical drive circuit 15 Horizontal drive circuit 101 Substrate 102 Organic EL element 102a Anode 102b Organic EL layer 102c Cathode 103 Sealing film 601 Substrate 602 TFT

Claims (10)

An organic semiconductor material comprising a compound represented by the following general formula (1):
Formula _{(1) A- (L 1 -Q} 1) m
(In the formula, A represents an acene structure in which three or more rings are condensed, L ₁ represents a divalent linking group, Q ₁ represents a substituent having a singlet oxygen quenching function, and m represents an integer of 1 to 4. Represents.) 2. The organic semiconductor material according to claim 1, wherein the organic semiconductor material is a compound represented by the general formula (1), wherein the linking group L ₁ is a group containing an ethynyl group. The organic semiconductor material according to claim 1 or 2, wherein the compound represented by the general formula (1) is a compound represented by the following general formula (2).

(In the formula, L ₂ represents a divalent linking group, Q ₂ represents a substituent having a singlet oxygen quenching function, and Z represents a substituted or unsubstituted aromatic ring.) The organic semiconductor material according to claim 1, wherein the substituent having a singlet oxygen quenching function is a cyclic amine structure. An organic semiconductor material comprising a compound represented by the following general formula (3):

(In the formula, L ₃ represents a linking group selected from a substituted or unsubstituted carbon atom, a nitrogen atom, an oxygen atom, a sulfur atom, and a single bond, and R _{1 to} R ₈ are a hydrogen atom, a halogen atom, a substituted or Represents an unsubstituted alkyl group, which may be linked to each other, and Z represents a substituted or unsubstituted aromatic ring.) 6. The compound represented by the general formula (2) or (3), wherein the aromatic ring represented by Z is an unsubstituted benzene ring. The organic semiconductor material described in 1. The organic-semiconductor film of any one of Claims 1-6 is contained, The organic-semiconductor film characterized by the above-mentioned. The organic semiconductor material according to any one of claims 1 to 6, which is formed by dissolving the organic semiconductor material according to any one of claims 1 to 6 in an organic solvent and applying and drying the obtained solution. Semiconductor film. The organic-semiconductor device using the organic-semiconductor material of any one of Claims 1-6. An organic thin film transistor using the organic semiconductor material according to claim 1 for a semiconductor layer.

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