JP2008103476A - Organic transistor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an organic transistor exhibiting stabilized transistor characteristics for a long time in which elements can be fabricated by a convenient process as compared with an inorganic semiconductor device. <P>SOLUTION: An organic semiconductor layer contains a compound represented by formula (1) in the organic transistor. In the formula, R<SP>1</SP>-R<SP>12</SP>represent a hydrogen atom or an organic residue. Adjoining R<SP>1</SP>-R<SP>8</SP>may form a ring. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an organic transistor having a thin film formed using an organic semiconductor.

  Field effect transistors (FETs) are widely used as important switching elements and amplifying elements along with bipolar transistors. Until now, transistors using silicon have been put into practical use and applied over a wide range. A field effect transistor exhibits its characteristics by controlling the transport of carriers in a semiconductor layer between a source electrode and a drain electrode using a gate electrode through an insulating layer. The case where the carrier is an electron is called n-type, and the case where the carrier is a hole is called p-type (monopolar element). A device capable of transporting both electron and hole carriers with respect to a monopolar device is called a bipolar device.

  In particular, an element using a metal oxide called a MOS (Metal Oxide Semiconductor) structure as an insulating layer is widely applied to a logic gate element, an inverter circuit, a memory element, and the like. Of these, MOS-FETs having a silicon dioxide thermal oxide film on silicon are well known.

  Since an inorganic semiconductor element represented by Si repeats a very complicated manufacturing process many times, its production requires enormous costs. Further, since a process of processing at a high temperature is included at the time of manufacture, it is difficult to use a flexible plastic substrate or an organic semiconductor. In contrast, in the case of an organic transistor, since an element using a plastic substrate can be manufactured, it is expected as a flexible and lightweight transistor.

  In recent years, devices using an organic material for an active layer, such as organic EL, organic laser, organic solar battery, and organic transistor, have attracted attention. As an advantage of using an organic semiconductor material, various materials can be designed, and many added values can be given. Taking organic transistors as an example, it does not require high-temperature processing, which was indispensable in conventional Si processes, so it can be fabricated on a plastic substrate and has the added value of being flexible, lightweight, and hard to break. Can be granted. In addition, the manufacturing process can be very simple, and a semiconductor material soluble in a solvent can be obtained depending on the design of the material. This makes it possible to apply printing methods such as screen printing and inkjet printing, which is very advantageous compared to inorganic semiconductors in terms of productivity and cost.

  The operational characteristics of a field effect transistor are greatly related to the capacitance of the insulating layer, the element configuration (channel length and channel width), and the carrier mobility of the semiconductor layer. In organic semiconductor materials, materials having high mobility are being actively developed. In addition, the deterioration of device characteristics due to aging is also a problem, and the development of highly stable organic semiconductor materials is also important.

JP 2001-94107 A JP 2002-198539 A Applied Physics Letters 2001, 78, 228 Advanced Materials 1999 1999 11 480

  An object of the present invention is to provide an organic transistor capable of producing an element by a simpler process than an inorganic semiconductor device and exhibiting stable transistor characteristics for a long time.

  The present invention relates to a transistor having a source electrode, a drain electrode, a gate electrode, and an organic semiconductor layer, wherein the organic semiconductor layer contains a compound represented by the following general formula [1]. .

General formula [1]

(In the formula, R ^{1 to} R ¹² each independently represents a hydrogen atom or a monovalent organic residue.

Moreover, adjacent substituents among R ^{1 to} R ⁸ may be connected to each other to form a ring. )

The present invention also relates to the above organic transistor, wherein R ¹¹ and R ¹² are hydrogen atoms.

  The present invention further relates to the organic transistor having a gate insulating film.

  According to the present invention, an organic transistor element having both an excellent ON / OFF ratio and high stability over time could be provided.

  The compound represented by the general formula [1] of the present invention will be described.

  In the present invention, the monovalent organic residue includes an alkyl group which may have a substituent, an aryl group which may have a substituent, an alkenyl group which may have a substituent, and a substituent. An alkynyl group which may have a substituent, an alkoxy group which may have a substituent, an aryloxy group which may have a substituent, an acyloxy group which may have a substituent, an alkyl which may have a substituent Sulfanyl group, arylsulfanyl group which may have a substituent, alkylsulfinyl group which may have a substituent, arylsulfinyl group which may have a substituent, alkylsulfonyl group which may have a substituent An arylsulfonyl group which may have a substituent, an acyl group which may have a substituent, an alkoxycarbonyl group which may have a substituent, a carbamoyl group which may have a substituent, Have Sulfamoyl group, optionally substituted amino group, optionally substituted phosphinoyl group, optionally substituted heteroaryl group, halogen group, nitro group, sulfonic acid group, hydroxyl group And a cyano group.

  As an alkyl group which may have a substituent, a C1-C20 alkyl group is preferable, More preferably, it is a C1-C6 alkyl group. For example, methyl group, ethyl group, propyl group, butyl group, hexyl group, octyl group, decyl group, dodecyl group, octadadecyl group, isopropyl group, isobutyl group, sec-butyl group, tert-butyl group, 1-ethylpentyl group , Cyclopentyl group, cyclohexyl group, trifluoromethyl group, 2-ethylhexyl group, phenacyl group, 1-naphthoylmethyl group, 2-naphthoylmethyl group, 4-methylsulfanylphenacyl group, 4-phenylsulfanylphenacyl group, 4-dimethylaminophenacyl group, 4-cyanophenacyl group 4-methylphenacyl group, 2-methylphenacyl group, 3-fluorophenacyl group, 3-trifluoromethylphenacyl group, 3-nitrophenacyl group, etc. A chain or branched alkyl group is exemplified. Furthermore, examples of the cyclic alkyl group (cycloalkyl ring) include cycloalkyl groups such as a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, and a cyclooctyl group.

  The aryl group that may have a substituent is preferably an aryl group having 6 to 30 carbon atoms, more preferably an aryl group having 6 to 14 carbon atoms. Phenyl group, biphenyl group, 1-naphthyl group, 2-naphthyl group, 9-anthryl group, 9-phenanthryl group, 1-pyrenyl group, 5-naphthacenyl group, 1-indenyl group, 2-azurenyl group, 9-fluorenyl group Terphenyl group, quarterphenyl group, o-, m-, and p-tolyl group, xylyl group, o-, m-, and p-cumenyl group, mesityl group, pentarenyl group, binaphthalenyl group, turnaphthalenyl group, quarternaphthalene Renyl group, heptaenyl group, biphenylenyl group, indacenyl group, fluoranthenyl group, acenaphthylenyl group, aceanthrylenyl group, phenalenyl group, fluorenyl group, anthryl group, bianthracenyl group, teranthracenyl group, quarteranthracenyl group, Anthraquinolyl, phenanthryl, Phenylenyl group, pyrenyl group, chrysenyl group, naphthacenyl group, preadenyl group, picenyl group, perylenyl group, pentaphenyl group, pentacenyl group, tetraphenylenyl group, hexaphenyl group, hexacenyl group, rubicenyl group, coronenyl group, trinaphthylenyl group , A heptaphenyl group, a heptacenyl group, a pyrantrenyl group, an obalenyl group, and the like.

  As an alkenyl group which may have a substituent, a C2-C10 alkenyl group is preferable, for example, a vinyl group, an allyl group, a styryl group etc. are mentioned.

  The alkynyl group which may have a substituent is preferably an alkynyl group having 2 to 10 carbon atoms, and examples thereof include an ethynyl group, a propynyl group, and a propargyl group.

  As an alkoxy group which may have a substituent, a C1-C20 alkoxy group is preferable, More preferably, it is a C1-C6 alkoxy group. For example, methoxy, ethoxy, propyloxy, isopropyloxy, butoxy, isobutoxy, sec-butoxy, tert-butoxy, pentyloxy, isopentyloxy, hexyloxy, heptyloxy, octyl Oxy group, 2-ethylhexyloxy group, decyloxy group, dodecyloxy group, octadecyloxy group, ethoxycarbonylmethyl group, 2-ethylhexyloxycarbonylmethyloxy group, aminocarbonylmethyloxy group, N, N-dibutylaminocarbonylmethyloxy group N-methylaminocarbonylmethyloxy group, N-ethylaminocarbonylmethyloxy group, N-octylaminocarbonylmethyloxy group, N-methyl-N-benzylaminocarbonylmethyloxy group, benzyloxy Group, cyanomethyloxy group and the like.

  The aryloxy group which may have a substituent is preferably an aryloxy group having 6 to 30 carbon atoms, more preferably an aryloxy group having 6 to 14 carbon atoms. For example, phenyloxy group, 1-naphthyloxy group, 2-naphthyloxy group, 2-chlorophenyloxy group, 2-methylphenyloxy group, 2-methoxyphenyloxy group, 2-butoxyphenyloxy group, 3-chlorophenyloxy group 3-trifluoromethylphenyloxy group, 3-cyanophenyloxy group, 3-nitrophenyloxy group, 4-fluorophenyloxy group, 4-cyanophenyloxy group, 4-methoxyphenyloxy group, 4-dimethylaminophenyl An oxy group, 4-methylsulfanylphenyloxy group, 4-phenylsulfanylphenyloxy group, etc. are mentioned.

  The acyloxy group which may have a substituent is preferably an acyloxy group having 2 to 20 carbon atoms, such as an acetyloxy group, a propanoyloxy group, a butanoyloxy group, a pentanoyloxy group, or trifluoromethylcarbonyloxy. Group, benzoyloxy group, 1-naphthylcarbonyloxy group, 2-naphthylcarbonyloxy group and the like.

  The alkylsulfanyl group which may have a substituent is preferably an alkylsulfanyl group having 1 to 20 carbon atoms. For example, a methylsulfanyl group, an ethylsulfanyl group, a propylsulfanyl group, an isopropylsulfanyl group, a butylsulfanyl group, or a hexylsulfanyl group. Group, cyclohexylsulfanyl group, octylsulfanyl group, 2-ethylhexylsulfanyl group, decanoylsulfanyl group, dodecanoylsulfanyl group, octadecanoylsulfanyl group, cyanomethylsulfanyl group, methoxymethylsulfanyl group and the like.

  The arylsulfanyl group which may have a substituent is preferably an arylsulfanyl group having 6 to 30 carbon atoms, and more preferably an arylsulfanyl group having 6 to 14 carbon atoms. For example, phenylsulfanyl group, 1-naphthylsulfanyl group, 2-naphthylsulfanyl group, 2-chlorophenylsulfanyl group, 2-methylphenylsulfanyl group, 2-methoxyphenylsulfanyl group, 2-butoxyphenylsulfanyl group, 3-chlorophenylsulfanyl group 3-trifluoromethylphenylsulfanyl group, 3-cyanophenylsulfanyl group, 3-nitrophenylsulfanyl group, 4-fluorophenylsulfanyl group, 4-cyanophenylsulfanyl group, 4-methoxyphenylsulfanyl group, 4-methylsulfanylphenyl A sulfanyl group, 4-phenylsulfanylphenylsulfanyl group, 4-dimethylaminophenylsulfanyl group and the like can be mentioned.

  The alkylsulfinyl group which may have a substituent is preferably an alkylsulfinyl group having 1 to 20 carbon atoms, and more preferably an alkylsulfinyl group having 1 to 6 carbon atoms. For example, methylsulfinyl group, ethylsulfinyl group, propylsulfinyl group, isopropylsulfinyl group, butylsulfinyl group, hexylsulfinyl group, cyclohexylsulfinyl group, octylsulfinyl group, 2-ethylhexylsulfinyl group, decanoylsulfinyl group, dodecanoylsulfinyl group, Examples include an octadecanoylsulfinyl group, a cyanomethylsulfinyl group, and a methoxymethylsulfinyl group.

  The arylsulfinyl group which may have a substituent is preferably an arylsulfinyl group having 6 to 30 carbon atoms, and more preferably an arylsulfinyl group having 6 to 14 carbon atoms. For example, phenylsulfinyl group, 1-naphthylsulfinyl group, 2-naphthylsulfinyl group, 2-chlorophenylsulfinyl group, 2-methylphenylsulfinyl group, 2-methoxyphenylsulfinyl group, 2-butoxyphenylsulfinyl group, 3-chlorophenylsulfinyl group 3-trifluoromethylphenylsulfinyl group, 3-cyanophenylsulfinyl group, 3-nitrophenylsulfinyl group, 4-fluorophenylsulfinyl group, 4-cyanophenylsulfinyl group, 4-methoxyphenylsulfinyl group, 4-methylsulfanylphenyl A sulfinyl group, 4-phenylsulfanylphenylsulfinyl group, 4-dimethylaminophenylsulfinyl group and the like can be mentioned.

  As an alkylsulfonyl group which may have a substituent, a C1-C20 alkylsulfonyl group is preferable, More preferably, it is a C1-C6 alkylsulfonyl group. For example, methylsulfonyl group, ethylsulfonyl group, propylsulfonyl group, isopropylsulfonyl group, butylsulfonyl group, hexylsulfonyl group, cyclohexylsulfonyl group, octylsulfonyl group, 2-ethylhexylsulfonyl group, decanoylsulfonyl group, dodecanoylsulfonyl group, Examples include an octadecanoylsulfonyl group, a cyanomethylsulfonyl group, and a methoxymethylsulfonyl group.

  The arylsulfonyl group which may have a substituent is preferably an arylsulfonyl group having 6 to 30 carbon atoms, and more preferably an arylsulfonyl group having 6 to 14 carbon atoms. For example, phenylsulfonyl group, 1-naphthylsulfonyl group, 2-naphthylsulfonyl group, 2-chlorophenylsulfonyl group, 2-methylphenylsulfonyl group, 2-methoxyphenylsulfonyl group, 2-butoxyphenylsulfonyl group, 3-chlorophenylsulfonyl group 3-trifluoromethylphenylsulfonyl group, 3-cyanophenylsulfonyl group, 3-nitrophenylsulfonyl group, 4-fluorophenylsulfonyl group, 4-cyanophenylsulfonyl group, 4-methoxyphenylsulfonyl group, 4-methylsulfanylphenyl Examples include a sulfonyl group, 4-phenylsulfanylphenylsulfonyl group, 4-dimethylaminophenylsulfonyl group and the like.

  The acyl group which may have a substituent is preferably an acyl group having 2 to 20 carbon atoms, for example, acetyl group, propanoyl group, butanoyl group, trifluoromethylcarbonyl group, pentanoyl group, benzoyl group, 1-naphthoyl. Group, 2-naphthoyl group, 4-methylsulfanylbenzoyl group, 4-phenylsulfanylbenzoyl group, 4-dimethylaminobenzoyl group, 4-diethylaminobenzoyl group, 2-chlorobenzoyl group, 2-methylbenzoyl group, 2-methoxybenzoyl Group, 2-butoxybenzoyl group, 3-chlorobenzoyl group, 3-trifluoromethylbenzoyl group, 3-cyanobenzoyl group, 3-nitrobenzoyl group, 4-fluorobenzoyl group, 4-cyanobenzoyl group, 4-methoxybenzoyl Groups and the like.

  The alkoxycarbonyl group which may have a substituent is preferably an alkoxycarbonyl group having 2 to 20 carbon atoms, such as a methoxycarbonyl group, ethoxycarbonyl group, propoxycarbonyl group, butoxycarbonyl group, hexyloxycarbonyl group, octyl. Oxycarbonyl group, decyloxycarbonyl group, octadecyloxycarbonyl group, phenoxycarbonyl group, trifluoromethyloxycarbonyl group, 1-naphthyloxycarbonyl group, 2-naphthyloxycarbonyl group, 4-methylsulfanylphenyloxycarbonyl group, 4- Phenylsulfanylphenyloxycarbonyl group, 4-dimethylaminophenyloxycarbonyl group, 4-diethylaminophenyloxycarbonyl group, 2-chlorophenyloxycarbonyl group Group, 2-methylphenyloxycarbonyl group, 2-methoxyphenyloxycarbonyl group, 2-butoxyphenyloxycarbonyl group, 3-chlorophenyloxycarbonyl group, 3-trifluoromethylphenyloxycarbonyl group, 3-cyanophenyloxycarbonyl group , 3-nitrophenyloxycarbonyl group, 4-fluorophenyloxycarbonyl group, 4-cyanophenyloxycarbonyl group, 4-methoxyphenyloxycarbonyl group and the like.

  The carbamoyl group which may have a substituent is preferably a carbamoyl group having 1 to 20 carbon atoms, and more preferably a carbamoyl group having 1 to 6 carbon atoms. For example, N-methylcarbamoyl group, N-ethylcarbamoyl group, N-propylcarbamoyl group, N-butylcarbamoyl group, N-hexylcarbamoyl group, N-cyclohexylcarbamoyl group, N-octylcarbamoyl group, N-decylcarbamoyl group, N-octadecylcarbamoyl group, N-acetylcarbamoyl group, N-phenylcarbamoyl group, N-2-methylphenylcarbamoyl group, N-2-chlorophenylcarbamoyl group, N-2-isopropoxyphenylcarbamoyl group, N-2- ( 2-ethylhexyl) phenylcarbamoyl group, N-3-chlorophenylcarbamoyl group, N-3-nitrophenylcarbamoyl group, N-3-cyanophenylcarbamoyl group, N-4-methoxyphenylcarbamoyl group, N-4-cyanopheny Carbamoyl group, N-4-methylsulfanylphenylcarbamoyl group, N-4-phenylsulfanylphenylcarbamoyl group, N-methyl-N-phenylcarbamoyl group, N, N-dimethylcarbamoyl group, N, N-dibutylcarbamoyl group, N N-diphenylcarbamoyl group and the like.

  The sulfamoyl group which may have a substituent is preferably a sulfamoyl group having 0 to 20 carbon atoms in total, for example, a sulfamoyl group, an N-alkylsulfamoyl group, an N-arylsulfamoyl group, N, N- Examples thereof include a dialkylsulfamoyl group, an N, N-diarylsulfamoyl group, and an N-alkyl-N-arylsulfamoyl group. More specifically, N-methylsulfamoyl group, N-ethylsulfamoyl group, N-propylsulfamoyl group, N-butylsulfamoyl group, N-hexylsulfamoyl group, N-cyclohexylsulfur group. Famoyl group, N-octylsulfamoyl group, N-2-ethylhexylsulfamoyl group, N-decylsulfamoyl group, N-octadecylsulfamoyl group, N-phenylsulfamoyl group, N-2- Methylphenylsulfamoyl group, N-2-chlorophenylsulfamoyl group, N-2-methoxyphenylsulfamoyl group, N-2-isopropoxyphenylsulfamoyl group, N-3-chlorophenylsulfamoyl group, N-3-nitrophenylsulfamoyl group, N-3-cyanophenylsulfamoyl group, N-4-methoxyphenyl Nylsulfamoyl group, N-4-cyanophenylsulfamoyl group, N-4-dimethylaminophenylsulfamoyl group, N-4-methylsulfanylphenylsulfamoyl group, N-4-phenylsulfanylphenylsulfamoyl Group, N-methyl-N-phenylsulfamoyl group, N, N-dimethylsulfamoyl group, N, N-dibutylsulfamoyl group, N, N-diphenylsulfamoyl group and the like.

The amino group which may have a substituent is preferably an amino group having 0 to 40 carbon atoms, and more preferably an amino group having 1 to 14 carbon atoms. For example, -NH _2, N- alkylamino group, N- arylamino group, N- acylamino group, N- sulfonylamino group, N, N- dialkylamino group, N, N- diarylamino group, N- alkyl -N -Arylamino group, N, N-disulfonylamino group, etc. are mentioned. More specifically, N-methylamino group, N-ethylamino group, N-propylamino group, N-isopropylamino group, N-butylamino group, N-tert-butylamino group, N-hexylamino group, N-cyclohexylamino group, N-octylamino group, N-2-ethylhexylamino group, N-decylamino group, N-octadecylamino group, N-benzylamino group, N-phenylamino group, N-2-methylphenylamino Group, N-2-chlorophenylamino group, N-2-methoxyphenylamino group, N-2-isopropoxyphenylamino group, N-2- (2-ethylhexyl) phenylamino group, N-3-chlorophenylamino group, N-3-nitrophenylamino group, N-3-cyanophenylamino group, N-3-trifluoromethylphenylamino group, -4-methoxyphenylamino group, N-4-cyanophenylamino group, N-4-trifluoromethylphenylamino group, N-4-methylsulfanylphenylamino group, N-4-phenylsulfanylphenylamino group, N- 4-dimethylaminophenylamino group, N-methyl-N-phenylamino group, N, N-dimethylamino group, N, N-diethylamino group, N, N-dibutylamino group, N, N-diphenylamino group, N N-diacetylamino group, N, N-dibenzoylamino group, N, N- (dibutylcarbonyl) amino group, N, N- (dimethylsulfonyl) amino group, N, N- (diethylsulfonyl) amino group, N N- (dibutylsulfonyl) amino group, N, N- (diphenylsulfonyl) amino group and the like.

  The phosphinoyl group which may have a substituent is preferably a phosphinoyl group having 2 to 50 carbon atoms, for example, dimethylphosphinoyl group, diethylphosphinoyl group, dipropylphosphinoyl group, diphenylphosphinoyl group. Group, dimethoxyphosphinoyl group, diethoxyphosphinoyl group, dibenzoylphosphinoyl group, bis (2,4,6-trimethylphenyl) phosphinoyl group and the like.

The heteroaryl group which may have a substituent is preferably an aromatic or aliphatic heterocyclic ring containing a nitrogen atom, an oxygen atom, a sulfur atom or a phosphorus atom. For example, thienyl group, benzo [b] thienyl group, naphtho [2,3-b] thienyl group, pyrrolyl group, thiantenyl group, furyl group, pyranyl group, isobenzofuranyl group, chromenyl group, xanthenyl group, phenoxathii Nyl group, 2H-pyrrolyl group, pyrrolyl group, imidazolyl group, pyrazolyl group, pyridyl group, pyrazinyl group, pyrimidinyl group, pyridazinyl group, indolizinyl group, isoindolyl group, 3H-indolyl group, indolyl group, 1H-indazolyl group, purinyl group 4H-quinolidinyl group, isoquinolyl group, quinolyl group, phthalazinyl group, naphthyridinyl group, quinoxanilyl group, quinazolinyl group, cinnolinyl group, pteridinyl group, 4aH-carbazolyl group, carbazolyl group, β-carbolinyl group, phenanthridinyl group, acridinini group Group, perimidinyl group, phenanthrolinyl group, phenazinyl group, phenalsadinyl group, isothiazolyl group, phenothiazinyl group, isoxazolyl group, furazanyl group, phenoxazinyl group, isochromanyl group, chromanyl group, pyrrolidinyl group, pyrrolinyl group, imidazolidinyl group, imidazolinyl group , Pyrazolidinyl group, pyrazolinyl group, piperidyl group, piperazinyl group, indolinyl group, isoindolinyl group, quinuclidinyl group, morpholinyl group, thioxanthryl group, carbazolyl group, acridinyl group, phenazinyl group, benzofuryl group, isothiazolyl group, isoxazolyl group, flazanyl group Phenoxazinyl group, benzothiazolyl group, benzoxazolyl group, benzimidazolyl group, benzotriazolyl group, pyranyl group, etc. .
Examples of the halogen group include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.

  Furthermore, the alkyl group which may have a substituent mentioned above, the aryl group which may have a substituent, the alkenyl group which may have a substituent, the alkynyl group which may have a substituent, a substituent An alkoxy group which may have a substituent, an aryloxy group which may have a substituent, an acyloxy group which may have a substituent, an alkylsulfanyl group which may have a substituent, and a substituent An arylsulfanyl group which may have a substituent, an alkylsulfinyl group which may have a substituent, an arylsulfinyl group which may have a substituent, an alkylsulfonyl group which may have a substituent, and a substituent. An arylsulfonyl group, an optionally substituted acyl group, an optionally substituted alkoxycarbonyl group, an optionally substituted carbamoyl group, an optionally substituted sulfamoyl group, Amino group which may have a group, hydrogen atom of the heteroaryl group which may have a even better phosphinoyl groups and substituents have a substituent may be further substituted with other substituents.

Examples of such substituents include halogen groups such as fluorine atom, chlorine atom, bromine atom and iodine atom, alkoxy groups such as methoxy group, ethoxy group and tert-butoxy group, aryl groups such as phenoxy group and p-tolyloxy group. Oxy group, methoxycarbonyl group, butoxycarbonyl group, alkoxycarbonyl group such as phenoxycarbonyl group, acetoxy group, propionyloxy group, acyloxy group such as benzoyloxy group, acetyl group, benzoyl group, isobutyryl group, acryloyl group, methacryloyl group, An acyl group such as a methoxalyl group, an alkylsulfanyl group such as a methylsulfanyl group or a tert-butylsulfanyl group, an arylsulfanyl group such as a phenylsulfanyl group or a p-tolylsulfanyl group, a methylamino group, or a cyclohexylamino group; Dialkylamino groups such as alkylamino group, dimethylamino group, diethylamino group, morpholino group, piperidino group, arylamino groups such as phenylamino group, p-tolylamino group, methyl group, ethyl group, tert-butyl group, dodecyl group, etc. In addition to aryl groups such as alkyl groups, phenyl groups, p-tolyl groups, xylyl groups, cumenyl groups, naphthyl groups, anthryl groups, phenanthryl groups, etc., hydroxy groups, carboxy groups, formyl groups, mercapto groups, sulfo groups, mesyl groups , P-toluenesulfonyl group, amino group, nitro group, cyano group, trifluoromethyl group, trichloromethyl group, trimethylsilyl group, phosphinico group, phosphono group, trimethylammoniumyl group, dimethylsulfoniumumyl group, triphenylphenacylphospho And niumyl group.
Furthermore, adjacent substituents of R1 to R8 may be connected to each other to form a ring. Examples thereof include those shown below, and these may have the above-described substituents.

  In the formula, A and B each independently represent O, S, NH, NEt, NPh, or the like.

In the general formula [1], R ¹¹ and R ¹² are preferably hydrogen atoms. The reason for this is that, as shown by the broken line in the figure below, an intermolecular network based on hydrogen bonds is constructed, stronger intermolecular forces are expressed, and molecular aggregates improve the stability of the entire system. And the like.

  Specific examples of the compound represented by the general formula [1] of the present invention are specifically exemplified below as exemplified compounds (1) to (110), but are not limited thereto. In the exemplified compounds, Me represents a methyl group, Et represents an ethyl group, Hex represents a hexyl group, Ph represents a phenyl group, and Tol represents a p-tolyl group.

  By using the compound represented by the general formula [1] as the active layer (organic semiconductor layer) of the organic transistor element, it is possible to provide a transistor with little deterioration with time. Any known organic transistor can be used as a specific configuration and specification of the organic transistor that can use the active layer.

  As a suitable structure, the structure of I-X shown in FIG. 1 is mentioned.

  In FIG. 1, A is a source electrode and a drain electrode (one of two electrodes is a source electrode and the other is a drain electrode), B is a gate electrode, C is an organic semiconductor layer, and D is a gate. An insulating film, E, represents a substrate. In FIG. 1, II, IV, VI, and VIII are examples in which the substrate also serves as the gate electrode.

  In order to use the compound represented by the general formula [1] as an active layer of an organic transistor element, it is desirable to form a film on a substrate by a vacuum deposition method. At this time, the characteristics can be improved by heating the substrate. In addition, a film dissolved in an appropriate organic solvent can be used to form a film on a substrate by spin coating, drop casting, an inkjet method, a screen printing method, or the like.

  Moreover, although a glass substrate or a silicon substrate can be used as a substrate, from the viewpoint of light weight and flexibility, polyethylene, polyethylene terephthalate, polyethylene naphthalate, polyethersulfone, polypropylene, polyimide, polycarbonate, cellulose triacetate, etc. A plastic film can also be used. Depending on the configuration of the element, the substrate itself may also serve as the electrode.

  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. Specifically, gold, platinum, palladium, aluminum, indium, calcium, potassium, magnesium, tin, lead, indium tin oxide (ITO), silver paste, carbon paste, graphite, glassy carbon, lithium, lithium fluoride / Aluminum laminate, calcium / aluminum laminate, silicon, ruthenium, manganese, yttrium, titanium and the like and alloys thereof are not limited thereto. Examples of alloys include magnesium / silver, magnesium / indium, lithium / aluminum, and the like, but are not limited thereto. The ratio of the alloy is controlled by the temperature of the vapor deposition source, the atmosphere, the degree of vacuum, etc., and is selected to an appropriate ratio. The source electrode, the drain electrode, and the gate electrode may be formed with a layer structure of two or more layers if necessary. Furthermore, a conductive electrode using an organic material such as conductive polypyrrole, conductive polythiophene, conductive polyaniline, or PEDOT / PSS can also be used.

  As a method for producing the electrode, any of dry film forming methods such as vacuum deposition, sputtering, plasma, and ion plating, and wet film forming methods such as spin coating, dipping, and flow coating can be applied. Further, it may be formed from the coating film by lithography or laser ablation.

  In addition, the surface of the electrode is modified by using a self-assembled monolayer (SAM) to reduce the surface energy of the electrode surface, so that the crystal growth of the organic semiconductor material, the crystal arrangement, the organic semiconductor material, The paintability with an electrode can be improved. For example, when a gold electrode is used, it is desirable to modify the surface with alkanethiol or the like.

  Various insulating films can be used as the gate insulating layer, and an inorganic oxide 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 yttrium trioxide. More preferred are silicon oxide, aluminum oxide, tantalum oxide, and titanium oxide. Inorganic nitrides such as silicon nitride and aluminum nitride can also be suitably used.

  As a method for forming a gate insulating film, a dry process such as a vacuum deposition method, 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, Examples include wet processes such as spray coating, spin coating, blade coating, dip coating, casting, roll coating, bar coating, die coating, and other coating methods, and printing and inkjet patterning methods. 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 an alkoxy solution is applied and dried is used.

  The hydrophilic gate insulating film can be changed from hydrophilic to hydrophobic by performing various chemical surface treatments. Thereby, the wettability of the gate insulating film and the hydrophobic organic semiconductor layer can be greatly improved, and the crystallinity of the semiconductor material can be improved. In addition, an effect of reducing leakage current can be obtained. Typical surface treatment materials include hexamethyldisilazane (HMDS), octyltrichlorosilane (OTS), 7-octenyltrichlorosilane (VTS), tridecafluoro-1,1,2,2-tetrahydrooctyltrichlorosilane. Silane-based materials such as (FTS) and benzyltrichlorosilane (BTS) are preferable, but are not limited thereto.

  Examples of the organic gate insulating film include polyethylene, vinyl chloride, polyimide, polyamide, polyester, polyvinyl phenol, polyvinyl alcohol, novolac resin, cyanoethyl pullulan, acrylonitrile, and parylene. Moreover, those copolymers can be used similarly.

  Hereinafter, the present invention will be described more specifically with reference to examples, but the present invention is not limited thereto.

Examples 1 to 19, 21, 22, 24 to 26, 28 to 40, 42 to 50, 52 to 59, 62 to 70, 72 to 89, 91 to 104, 109, 110
A thermal oxide film was formed on a Si wafer having a resistivity of 0.02 Ω · cm as a gate electrode to form a gate insulating layer, and then surface treatment was performed using hexamethyldisilazane (HMDS). 70 nm of the compounds of the present invention shown in Table 1 were laminated by a vacuum deposition method (degree of vacuum: 2.2 × 10 ⁻⁶ torr, deposition rate: 0.05 nm / sec). Further, gold was deposited on the surface of the film using a mask to form a source electrode and a drain electrode. An organic transistor element having a source electrode and drain electrode thickness of 300 nm, a channel width W = 5 mm, and a channel length L = 20 μm was produced.

Examples 20, 23, 27, 41, 51, 60, 61, 71, 90, 105-108
A thermal oxide film was formed on a Si wafer having a resistivity of 0.02 Ω · cm as a gate electrode to form a gate insulating layer, and then surface treatment was performed using hexamethyldisilazane (HMDS). A semiconductor layer (100 nm) made of the compound of the present invention shown in Table 1 was formed by spin coating (DMSO solvent), and heat treatment was performed in a nitrogen atmosphere at 80 ° C. for 60 minutes, and then at 120 ° C. for 60 minutes. . Furthermore, gold was deposited on the surface of the semiconductor layer using a mask to form source and drain electrodes. An organic transistor element having a source and drain electrode thickness of 300 nm, a channel width W = 5 mm, and a channel length L = 20 μm was produced.

Comparative Example 1
Instead of the compound of the present invention, the following compound A was used, and an organic transistor element was produced in the same manner as in Example 1.

Compound A

  Using the organic transistor element produced as described above, the transistor element was stored under the condition of 40 ° C. in the atmosphere, and the change in the transistor characteristics over time was compared. The maximum current value (ON current) between the source electrode and the drain electrode when a voltage of 30 V or −30 V is applied between the source electrode and the drain electrode and the gate electrode is swept in the range of −50 V to 50 V. ) And the minimum current value (OFF current) was defined as the ON / OFF ratio. In each element, the relative values of the ON / OFF ratio after one day, one week, and one month when the ON / OFF ratio immediately after the element production was 1 were as follows.

Table 1

  Conventionally known organic semiconductor materials are known to be doped with oxygen or the like in the thin film and left to deteriorate in characteristics when left in the atmosphere. However, it can be seen that the organic transistor element produced using the semiconductor material of the present invention for the active layer exhibits high stability over time even in the atmosphere.

It is a conceptual diagram which shows one embodiment of a structure of the organic transistor of this invention.

Explanation of symbols

A Source electrode or drain electrode B Gate electrode C Organic semiconductor layer D Gate insulating film E Substrate

Claims (3)

A transistor having a source electrode, a drain electrode, a gate electrode, and an organic semiconductor layer, wherein the organic semiconductor layer contains a compound represented by the following general formula [1].
General formula [1]

(In the formula, R ^{1 to} R ¹² each independently represents a hydrogen atom or a monovalent organic residue.
Moreover, adjacent substituents among R ^{1 to} R ⁸ may be connected to each other to form a ring. ) The organic transistor according to claim 1, wherein R ¹¹ and R ¹² are hydrogen atoms.   The organic transistor according to claim 1, further comprising a gate insulating film.

Images