JP2005154709A - Organic semiconductor material, organic thin film transistor and method for producing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a stable organic semiconductor material, capable of being produced in a simple method of a wet process, having a high carrier mobility, showing a good transistor characteristic having a high on off ratio, and hardly changing with time, and an organic thin film transistor by using the organic semiconductor material. <P>SOLUTION: This organic semiconductor material consists mainly of a mixture consisting of a polymer having a recurring unit expressed by the following general formula (1) and compounds expressed by 4-diphenylaminostilbene, 4-di-p-tolylaminostilbene, 4'-diphenylamino-α-phenylstilbene, 4'-di-p-tolylamino-α-phenylstilbene, etc. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an organic semiconductor material, an organic thin film transistor having a layer made of the organic semiconductor material, and a method for manufacturing the same.

  Field effect thin film transistors (TFTs) having an organic active layer have attracted much attention in recent years as an inexpensive alternative to silicon-based TFTs. By configuring a device using an organic material, a circuit can be easily formed by a wet method such as a printing method, a spin coating method, or an immersion method. That is, it is possible to manufacture a device without going through a costly process required in the manufacturing process of the silicon-based TFT, and it is expected that the manufacturing cost is greatly reduced and the area is increased. In addition, the advantages of organic material-based devices include mechanical flexibility and weight reduction. At present, organic materials are not as good as inorganic semiconductor materials in terms of carrier mobility, but organic semiconductor devices are attracting much attention because of these advantages.

  The configuration and operation of the organic TFT will be described. FIG. 1A (note that FIG. 1A is a structural example of the organic thin film transistor of the present invention, but a description of the structure other than the material will be given with reference to FIG. 1A) is representative. It is sectional drawing of organic TFT. When a voltage is applied between the pair of electrodes (source electrode and drain electrode) in FIG. 1A, a current flows between the source electrode and the drain electrode through the organic semiconductor layer. At this time, when a voltage is applied to the gate electrode separated from the organic semiconductor layer by the insulating layer, the electric conductivity of the organic semiconductor layer changes due to the electric field effect, and therefore the current flowing between the source and drain electrodes can be modulated. This is considered to be because the width of the storage layer in the organic semiconductor layer adjacent to the insulating layer changes depending on the gate voltage, and the channel cross-sectional area changes.

  As a semiconductor material of such an organic TFT, for example, pentacene (Non-Patent Document 1), phthalocyanine (Non-Patent Document 2), fullerene (Patent Document 1, Non-Patent Document 3), anthracithiophene (Patent Document) 2), thiophene oligomers (Patent Literature 3, Non-Patent Literature 4), bisdithienothiophene (Non-Patent Literature 5), etc., and polymer materials such as polythiophene (Non-Patent Literature 6), polythienylene vinylene (non-patent literature) 7) Several materials such as polyarylamine (Patent Document 4) have been proposed.

The above materials have attractive carrier mobility as organic semiconductors for TFT devices. However, in order to apply to a TFT device using a commercial organic semiconductor, it is required to improve these materials in several points. For example, pentacene has been reported to have a mobility of about 1 cm ² / Vs. However, pentacene is hardly soluble in a solvent, and it is difficult to form a pentacene film from a solution. Pentacene also tends to oxidize over time in an oxygen-containing atmosphere and is unstable to oxidation. Similarly, phthalocyanine, fullerene, etc. have low solubility in solvents. Generally, semiconductor layers must be prepared using vacuum deposition, which is characteristic of organic-based devices such as low manufacturing cost and large area. Can not enjoy the benefits. In addition, these materials also have a problem that the film may be peeled off or cracked due to deformation of the substrate.

  In addition, polyalkylthiophene-based materials (Appl. Phys. Lett., 69, 4108, 1996.) are attracting attention as materials that can be wet-coated. However, the device has a low on-off ratio and is oxidized. There is a drawback that the characteristics easily change with time. Polyarylamine-based materials (Patent Document 4) have also been proposed, but higher mobility is demanded.

As described above, although several materials have been proposed as organic semiconductor materials for TFTs, an organic semiconductor material satisfying all necessary characteristics has not been obtained yet. In addition to showing good transistor characteristics, preferred organic semiconductor materials show good film solubility in a solvent that can be produced by a wet process, plus storage stability including oxidation resistance. Is required.
JP-A-8-228034 JP-A-11-195790 Japanese Patent No. 3145294 Japanese Patent Application No. 2003-35582 Japanese Patent Application No. 2003-307561 Japanese Patent Application No. 2003-185402 Japanese Patent Publication No. 2-24864 Japanese Patent Publication No. 3-39306 Japanese Examined Patent Publication No. 4-66023 Synth. Met. , 51, 419, 1992 Appl. Phys. Lett. 69, 3066, 1996 Appl. Phys. Lett. , 67, 121, 1995 Chem. Mater. , 4,457, 1998 Appl. Phys. Lett. , 71, 3871, 1997 Appl. Phys. Lett. 69, 4108, 1996. Appl. Phys. Lett. 69, 4108, 1996.

  The present invention has been made in order to solve these problems, and can be fabricated by a simple method using a wet process, has a high carrier mobility, a high on / off ratio, good transistor characteristics, and is stable over time. An object of the present invention is to provide an organic semiconductor material, an organic thin film transistor using the organic semiconductor material, and a manufacturing method thereof.

  As a result of intensive studies to achieve the above object, the present inventors have found that it is effective for the above object to use a mixture of a polymer having a specific structure and a low molecular compound as a semiconductor layer of an organic TFT. The present invention has been completed.

That is, according to the present invention, the following organic semiconductor material, organic thin film transistor, and manufacturing method thereof are provided.
(1) An organic semiconductor material comprising as a main component a mixture comprising a polymer having a repeating unit represented by the following general formula (I) and a compound represented by the following general formula (II).

〔式（Ｉ）中、Ａｒ^１は置換もしくは無置換の芳香族炭化水素基を表し、Ａｒ^２、Ａｒ^３はそれぞれ独立に置換もしくは無置換の、単環式、非縮合多環式または縮合多環式芳香族炭化水素基の２価基を表す。Ａｒ^４はベンゼン、チオフェン、ビフェニル、アントラセンの２価基を表し、これらは置換基を有していてもよい。〕

[In formula (I), Ar ¹ represents a substituted or unsubstituted aromatic hydrocarbon group, and Ar ² and Ar ³ are each independently substituted or unsubstituted monocyclic, non-condensed polycyclic or condensed poly Represents a divalent group of a cyclic aromatic hydrocarbon group. Ar ⁴ represents a divalent group of benzene, thiophene, biphenyl, and anthracene, and these may have a substituent. ]

〔式（ＩＩ）中、ｎは０または１の整数、Ａｒ’は置換もしくは無置換のアリール基を表し、Ｒ^１は水素原子、置換もしくは無置換のアルキル基あるいは置換もしくは無置換のアリール基を表し、Ｒ^２は水素原子、置換もしくは無置換のアルキル基あるいは置換もしくは無置換のアリール基を表し、Ａｒ’とＲ^１は共同で環を形成してもよい。

[In the formula (II), n represents an integer of 0 or 1, Ar ′ represents a substituted or unsubstituted aryl group, R ¹ represents a hydrogen atom, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group. R ² represents a hydrogen atom, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group, and Ar ′ and R ¹ may form a ring together.

  A represents a group represented by the following general formulas (1) and (2), a 9-anthryl group, or a substituted or unsubstituted carbazolyl group.

式（１）（２）中、Ｒ^３およびＲ^４は水素原子、アルキル基、アルコキシル基、ハロゲン原子、又は下記一般式（３）で示される基を表す。

In formulas (1) and (2), R ³ and R ⁴ represent a hydrogen atom, an alkyl group, an alkoxyl group, a halogen atom, or a group represented by the following general formula (3).

式（３）中、Ｒ^５およびＲ^６は置換もしくは無置換のアルキル基、置換または無置換のアリール基を表し、Ｒ^５およびＲ^６は同一でも異なっていてもよく、Ｒ^５およびＲ^６は互いに結合して環を形成してもよい。〕
（２）前記一般式（Ｉ）で示される繰り返し単位が、下記一般式（ＩＩＩ）で示される繰り返し単位であることを特徴とする前記（１）に記載の有機半導体材料。

In formula (3), R ⁵ and R ⁶ represent a substituted or unsubstituted alkyl group or a substituted or unsubstituted aryl group, R ⁵ and R ⁶ may be the same or different, and R ⁵ and R ⁶ are They may combine with each other to form a ring. ]
(2) The organic semiconductor material as described in (1) above, wherein the repeating unit represented by the general formula (I) is a repeating unit represented by the following general formula (III).

〔式（ＩＩＩ）中、Ａｒ^１は置換もしくは無置換の芳香族炭化水素基を表し、Ａｒ^４はベンゼン、チオフェン、ビフェニル、アントラセンの２価基を表し、これらは置換基を有していてもよい。Ｒ^７、Ｒ^８はそれぞれ独立にハロゲン原子、置換もしくは無置換の、アルキル基またはアルコキシ基もしくはアルキルチオ基から選択される基を表し、ｘ、ｙはそれぞれ独立に０から４の整数を表し、Ｒ^７、Ｒ^８が各々複数存在する場合には、同一でも別異でもよい。〕
（３）前記一般式（ＩＩＩ）で示される繰り返し単位が、下記一般式（ＩＶ）で示される繰り返し単位であることを特徴とする前記（２）に記載の有機半導体材料。

[In Formula (III), Ar ¹ represents a substituted or unsubstituted aromatic hydrocarbon group, Ar ⁴ represents a divalent group of benzene, thiophene, biphenyl, and anthracene, and these may have a substituent. Good. R ⁷ and R ⁸ each independently represent a halogen atom, a substituted or unsubstituted alkyl group, an alkoxy group or an alkylthio group, x and y each independently represents an integer of 0 to 4, ⁷ and R ⁸ may be the same or different when there are a plurality of R ^{8 s} . ]
(3) The organic semiconductor material as described in (2) above, wherein the repeating unit represented by the general formula (III) is a repeating unit represented by the following general formula (IV).

〔式（ＩＶ）中、Ａｒ^４はベンゼン、チオフェン、ビフェニル、アントラセンの２価基を表し、これらは置換基を有していてもよい。Ｒ^７、Ｒ^８はそれぞれ独立にハロゲン原子、置換もしくは無置換の、アルキル基またはアルコキシ基もしくはアルキルチオ基から選択される基を表し、Ｒ^９はハロゲン原子、置換もしくは無置換の、アルキル基、アルコキシ基、アルキルチオ基、アリール基から選択される基を表す。ｘ、ｙはそれぞれ独立に０から４の整数を表し、ｚは０から５の整数を表し、Ｒ^７、Ｒ^８、Ｒ^９が各々複数存在する場合には、同一でも別異でもよい。〕
（４）前記一般式（ＩＩＩ）で示される繰り返し単位が、下記一般式（Ｖ）で示される繰り返し単位であることを特徴とする前記（２）に記載の有機半導体材料。

[In the formula (IV), Ar ⁴ represents a divalent group of benzene, thiophene, biphenyl, or anthracene, and these may have a substituent. R ⁷ and R ⁸ each independently represent a halogen atom, a substituted or unsubstituted alkyl group, an alkoxy group or an alkylthio group, and R ⁹ represents a halogen atom, a substituted or unsubstituted alkyl group, an alkoxy group Represents a group selected from a group, an alkylthio group, and an aryl group. x and y each independently represents an integer of 0 to 4, z represents an integer of 0 to 5, and when there are a plurality of R ⁷ , R ⁸ and R ⁹ , they may be the same or different. ]
(4) The organic semiconductor material as described in (2) above, wherein the repeating unit represented by the general formula (III) is a repeating unit represented by the following general formula (V).

〔式（Ｖ）中、Ａｒ^４はベンゼン、チオフェン、ビフェニル、アントラセンの２価基を表し、これらは置換基を有していてもよい。Ｒ^７、Ｒ^８、Ｒ^１０、Ｒ^１１、Ｒ^１２、Ｒ^１３はそれぞれ独立にハロゲン原子、置換もしくは無置換の、アルキル基またはアルコキシ基もしくはアルキルチオ基から選択される基を表す。ｖは０から３の整数を表し、ｗ、ｘ、ｙはそれぞれ独立に０から４の整数を表し、Ｒ^７、Ｒ^８、Ｒ^１０、Ｒ^１１が各々複数存在する場合には、同一でも別異でもよい。〕
（５）前記一般式（Ｉ）で示される繰り返し単位が、下記一般式（ＶＩ）で示される繰り返し単位であることを特徴とする前記（１）に記載の有機半導体材料。

[In the formula (V), Ar ⁴ represents a divalent group of benzene, thiophene, biphenyl, or anthracene, and these may have a substituent. R ⁷ , R ⁸ , R ¹⁰ , R ¹¹ , R ¹² , and R ¹³ each independently represent a halogen atom, a substituted or unsubstituted alkyl group, an alkoxy group, or an alkylthio group. v represents an integer of 0 to 3, w, x, and y each independently represents an integer of 0 to 4, and when there are a plurality of R ⁷ , R ⁸ , R ¹⁰ , and R ¹¹ , they may be the same or different. It may be different. ]
(5) The organic semiconductor material as described in (1) above, wherein the repeating unit represented by the general formula (I) is a repeating unit represented by the following general formula (VI).

〔式（ＶＩ）中、Ａｒ^１は置換もしくは無置換の芳香族炭化水素基を表し、Ａｒ^４はベンゼン、チオフェン、ビフェニル、アントラセンの２価基を表し、これらは置換基を有していてもよい。Ｒ^１４、Ｒ^１５、Ｒ^１６、Ｒ^１７はそれぞれ独立にハロゲン原子、置換もしくは無置換の、アルキル基またはアルコキシ基もしくはアルキルチオ基から選択される基を表し、ｒ、ｓ、ｔ、ｕはそれぞれ独立に０から４の整数を表し、Ｒ^１４、Ｒ^１５、Ｒ^１６、Ｒ^１７が各々複数存在する場合には、同一でも別異でもよい。〕
（６）該一般式（ＶＩ）で示される繰り返し単位が、下記一般式（ＶＩＩ）で示される繰り返し単位であることを特徴とする前記（５）に記載の有機半導体材料。

[In the formula (VI), Ar ¹ represents a substituted or unsubstituted aromatic hydrocarbon group, Ar ⁴ represents a divalent group of benzene, thiophene, biphenyl, and anthracene, and these may have a substituent. Good. R ¹⁴ , R ¹⁵ , R ¹⁶ and R ¹⁷ each independently represents a halogen atom, a substituted or unsubstituted alkyl group, an alkoxy group or an alkylthio group, and r, s, t and u each independently Represents an integer of 0 to 4, and a plurality of R ¹⁴ , R ¹⁵ , R ¹⁶ and R ¹⁷ may be the same or different. ]
(6) The organic semiconductor material as described in (5) above, wherein the repeating unit represented by the general formula (VI) is a repeating unit represented by the following general formula (VII).

〔（ＶＩＩ）式中、Ａｒ^４はベンゼン、チオフェン、ビフェニル、アントラセンの２価基を表し、これらは置換基を有していてもよい。Ｒ^１４、Ｒ^１５、Ｒ^１６、Ｒ^１７、Ｒ^１８ はそれぞれ独立にハロゲン原子、置換もしくは無置換の、アルキル基またはアルコキシ基もしくはアルキルチオ基から選択される基を表し、ｑは０から５の整数を表し、ｒ、ｓ、ｔ、ｕはそれぞれ独立に０から４の整数を表し、Ｒ^１４、Ｒ^１５、Ｒ^１６、Ｒ^１７、Ｒ^１８が各々複数存在する場合には、同一でも別異でもよい。〕
（７）前記一般式（Ｉ）で示される繰り返し単位が、下記一般式（ＶＩＩＩ）で示される繰り返し単位であることを特徴とする前記（１）に記載の有機半導体材料。

[In the formula (VII), Ar ⁴ represents a divalent group of benzene, thiophene, biphenyl, or anthracene, and these may have a substituent. R ¹⁴ , R ¹⁵ , R ¹⁶ , R ¹⁷ and R ¹⁸ each independently represent a halogen atom, a substituted or unsubstituted alkyl group, an alkoxy group or an alkylthio group, and q is an integer of 0 to 5 And r, s, t, and u each independently represent an integer of 0 to 4, and when there are a plurality of R ¹⁴ , R ¹⁵ , R ¹⁶ , R ¹⁷ , and R ¹⁸ , they may be the same or different. Good. ]
(7) The organic semiconductor material as described in (1) above, wherein the repeating unit represented by the general formula (I) is a repeating unit represented by the following general formula (VIII).

〔式（ＶＩＩＩ）中、Ａｒ^１は置換または無置換の芳香族炭化水素基を表し、Ｒ^７、Ｒ^８、Ｒ^１９はそれぞれ独立に水素原子、ハロゲン原子、置換もしくは無置換の、アルキル基またはアルコキシ基もしくはアルキルチオ基から選択される基を表し、ｐ、ｘ、ｙはそれぞれ独立に０から４の整数を表し、Ｒ^７、Ｒ^８、Ｒ^９が各々複数存在する場合には、同一でも別異でもよい。〕
（８）前記一般式（ＶＩＩＩ）で示される繰り返し単位が、下記一般式（ＩＸ）で示される繰り返し単位であることを特徴とする前記（７）に記載の有機半導体材料。

[In the formula (VIII), Ar ¹ represents a substituted or unsubstituted aromatic hydrocarbon group, and R ⁷ , R ⁸ and R ¹⁹ each independently represent a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group or Represents a group selected from an alkoxy group or an alkylthio group, p, x and y each independently represents an integer of 0 to 4, and when there are a plurality of R ⁷ , R ⁸ and R ⁹ , they may be the same or different. It may be different. ]
(8) The organic semiconductor material as described in (7) above, wherein the repeating unit represented by the general formula (VIII) is a repeating unit represented by the following general formula (IX).

〔式（ＩＸ）中、Ｒ^７、Ｒ^８、Ｒ^１９、Ｒ^２０はそれぞれ独立にハロゲン原子、置換もしくは無置換の、アルキル基またはアルコキシ基もしくはアルキルチオ基から選択される基を表し、ｎは０から５の整数を示し、ｐ、ｘ、ｙはそれぞれ独立に０から４の整数を表し、Ｒ^７、Ｒ^８、Ｒ^１９、Ｒ^２０が各々複数存在する場合には、同一でも別異でもよい。〕
（９）前記一般式（ＶＩＩＩ）で示される繰り返し単位が、下記一般式（Ｘ）で示される繰り返し単位であることを特徴とする前記（７）に記載の有機半導体材料。

[In formula (IX), R ⁷ , R ⁸ , R ¹⁹ and R ²⁰ each independently represents a halogen atom, a substituted or unsubstituted alkyl group, an alkoxy group or an alkylthio group, and n is 0 To p, x and y each independently represents an integer from 0 to 4, and when there are a plurality of R ⁷ , R ⁸ , R ¹⁹ and R ²⁰ , they may be the same or different. . ]
(9) The organic semiconductor material as described in (7) above, wherein the repeating unit represented by the general formula (VIII) is a repeating unit represented by the following general formula (X).

〔式（Ｘ）中、Ｒ^７、Ｒ^８、Ｒ^１９、Ｒ^２１、Ｒ^２２はそれぞれ独立にハロゲン原子、置換もしくは無置換の、アルキル基またはアルコキシ基もしくはアルキルチオ基から選択される基を表し、ｌは０から５の整数を示し、ｍ、ｐ、ｖ、ｘ、ｙはそれぞれ独立に０から４の整数を表し、Ｒ^７、Ｒ^８、Ｒ^１９、Ｒ^２１、Ｒ^２２が各々複数存在する場合には、同一でも別異でもよい。〕
（１０）前記一般式（ＶＩＩＩ）で示される繰り返し単位が、下記一般式（ＸＩ）で示される繰り返し単位であることを特徴とする前記（７）に記載の有機半導体材料。

[In the formula (X), R ⁷ , R ⁸ , R ¹⁹ , R ²¹ and R ²² each independently represents a halogen atom, a substituted or unsubstituted alkyl group, an alkoxy group or an alkylthio group, l represents an integer of 0 to 5, m, p, v, x, and y each independently represents an integer of 0 to 4, and there are a plurality of R ⁷ , R ⁸ , R ¹⁹ , R ²¹ , and R ²² , respectively. In some cases, they may be the same or different. ]
(10) The organic semiconductor material as described in (7) above, wherein the repeating unit represented by the general formula (VIII) is a repeating unit represented by the following general formula (XI).

〔式中、Ｒ^７、Ｒ^８、Ｒ^１９、Ｒ^２３、Ｒ^２４、Ｒ^２５、Ｒ^２６はそれぞれ独立にハロゲン原子、置換もしくは無置換で、直鎖または分岐鎖のアルキル基またはアルコキシ基もしくはアルキルチオ基から選択される基を表し、ｊは０から３の整数を示し、ｋ、ｐ、ｘ、ｙはそれぞれ独立に０から４の整数を表し、Ｒ^７、Ｒ^８、Ｒ^１９、Ｒ^２３、Ｒ^２４が各々複数存在する場合には、同一でも別異でもよい。〕
（１１）前記一般式（Ｉ）、（ＩＩＩ）、（ＩＶ）、（Ｖ）、（ＶＩ）、（ＶＩＩ）、（ＶＩＩＩ）、（ＩＸ）、（Ｘ）、又は（ＸＩ）で示される繰り返し単位において、該繰り返し単位が少なくとも一つの炭素数２〜１８の置換または無置換で直鎖または分岐鎖の、アルキル基またはアルコキシ基もしくはアルキルチオ基を有することを特徴とする前記（１）〜（１０）いずれかに記載の有機半導体材料。
（１２）前記（１）〜（１０）のいずれかに記載の有機半導体材料と、該有機半導体材料を通じて電流を流すための対をなす電極を設けてなる構造体と、第三の電極とからなることを特徴とする有機薄膜トランジスタ。
（１３）前記第三の電極が、該構造体に絶縁体を介して設けられていることを特徴とする前記（１２）に記載の有機薄膜トランジスタ。
（１４）前記（１）〜（１０）のいずれかに記載の一般式（Ｉ）、（ＩＩＩ）、（ＩＶ）、（Ｖ）、（ＶＩ）、（ＶＩＩ）、（ＶＩＩＩ）、（ＩＸ）、（Ｘ）、又は（ＸＩ）で示される繰り返し単位を有する重合体と、前記（１）に記載の一般式（ＩＩ）で示される化合物からなる混合物を主成分とする有機半導体材料の溶液を塗布した後、溶媒を乾燥させて有機半導体層を形成する工程を含むことを特徴とする有機薄膜トランジスタの製造方法。
（１５）前記有機半導体層を、表面エネルギーが２５ｍＮ／ｍ以上４０ｍＮ／ｍ以下の値を持つゲート絶縁膜上に積層することを特徴とする前記（１４）に記載の有機薄膜トランジスタの製造方法。
（１６）前記ゲート絶縁膜がシランカップリング処理により表面改質されたものであることを特徴とする前記（１５）に記載の有機薄膜トランジスタの製造方法。
（１７）前記（１４）〜（１６）のいずれかの製造方法により得られることを特徴とする有機薄膜トランジスタ。

[Wherein R ⁷ , R ⁸ , R ¹⁹ , R ²³ , R ²⁴ , R ²⁵ , R ²⁶ are each independently a halogen atom, a substituted or unsubstituted, linear or branched alkyl group, alkoxy group or alkylthio Represents a group selected from the group, j represents an integer of 0 to 3, k, p, x, y each independently represents an integer of 0 to 4, R ⁷ , R ⁸ , R ¹⁹ , R ²³ , When a plurality of R ²⁴ are present, they may be the same or different. ]
(11) Repeat represented by the general formula (I), (III), (IV), (V), (VI), (VII), (VIII), (IX), (X), or (XI) In the unit, the repeating unit has at least one substituted or unsubstituted linear or branched alkyl group, alkoxy group or alkylthio group having 2 to 18 carbon atoms. ) Organic semiconductor material according to any one of the above.
(12) From the organic semiconductor material according to any one of (1) to (10), a structure provided with a pair of electrodes for passing a current through the organic semiconductor material, and a third electrode An organic thin film transistor characterized by comprising:
(13) The organic thin film transistor according to (12), wherein the third electrode is provided in the structure via an insulator.
(14) The general formula (I), (III), (IV), (V), (VI), (VII), (VIII), (IX) according to any one of (1) to (10) , (X) or (XI) a solution of an organic semiconductor material mainly composed of a mixture of a polymer having a repeating unit represented by (XI) and a compound represented by the general formula (II) described in (1) above A method for producing an organic thin film transistor comprising a step of forming an organic semiconductor layer by drying a solvent after coating.
(15) The method for producing an organic thin film transistor according to (14), wherein the organic semiconductor layer is stacked on a gate insulating film having a surface energy of 25 mN / m or more and 40 mN / m or less.
(16) The method for producing an organic thin film transistor according to (15), wherein the gate insulating film is surface-modified by silane coupling treatment.
(17) An organic thin film transistor obtained by the production method according to any one of (14) to (16).

  The structure of Claims 1-10 provides the organic-semiconductor material which was excellent in cost performance, and excellent in a mobility, an on-off ratio, and environmental tolerance.

  According to the structure of claim 11, an organic semiconductor material excellent in cost performance that can be easily manufactured by a wet film forming technique, which can achieve good solubility in a solvent that has been impossible with a conventionally known pentacene and phthalocyanine material. Provided.

  According to the structure of claim 12, an organic thin film transistor excellent in cost performance, mobility, on / off ratio, and environmental resistance is provided.

  According to the structure of the thirteenth aspect, it is possible to provide an excellent insulated gate type field effect organic thin film transistor which is excellent in cost performance because it can be easily manufactured by a wet film forming technique and which exhibits good characteristics.

  By the structure of Claims 14-16, the wet manufacturing method excellent in the cost performance of the outstanding organic thin-film transistor which shows a favorable characteristic is provided.

  Next, the present invention will be described in detail with reference to the accompanying drawings.

  1A, 1B, 1C, and 1D are examples of schematic views showing the structure of an organic TFT according to the present invention. The organic semiconductor layer of the organic TFT according to the present invention is made of an organic semiconductor material whose main component is a mixture of a polymer having a specific repeating unit and a specific compound. The device is provided with a spatially separated gate electrode, source electrode, and drain electrode, and an insulating layer is provided between the gate electrode and the organic semiconductor layer. In the TFT device, the current flowing in the organic semiconductor layer between the source electrode and the drain electrode is controlled by applying a voltage to the gate electrode.

  That is, in the device of the present invention, the organic semiconductor material constituting the organic semiconductor layer (hereinafter also referred to as the active layer) has a polymer having a repeating unit represented by the following general formula (I) as the first component. .

〔式（Ｉ）中、Ａｒ^１は置換もしくは無置換の芳香族炭化水素基を表し、Ａｒ^２、Ａｒ^３はそれぞれ独立に置換もしくは無置換の、単環式、非縮合多環式または縮合多環式芳香族炭化水素基の２価基を表す。Ａｒ^４はベンゼン、チオフェン、ビフェニル、アントラセンの２価基を表し、これらは置換基を有していてもよい。〕
上記重合体は、芳香環上に置換基を有していてもよい。溶解性の向上の観点からはアルキル基やアルコキシ基、アルキルチオ基などが挙げられる。これら置換基の炭素数が増加すれば溶解性はより向上するが、その反面キャリア移動度は低下してしまうため、溶解性が損なわれない範囲で所望の特性が得られるような置換基を選択することが好ましい。その場合の好適な置換基の例としては炭素数が１〜２５のアルキル基、アルコキシ基及びアルキルチオ基が挙げられる。更に好適には、炭素数が２〜１８のアルキル基、アルコキシ基及びアルキルチオ基が挙げられる。これらの置換基は同一のものを複数導入してもよいし、異なるものを複数導入してもよい。また、これらのアルキル基、アルコキシ基及びアルキルチオ基は、さらにハロゲン原子、シアノ基、フェニル基、ヒドロキシル基、カルボキシル基、または炭素数１〜１２の直鎖、分岐鎖もしくは環状のアルキル基、アルコキシ基あるいはアルキルチオ基で置換されたフェニル基を含有していてもよい。

[In formula (I), Ar ¹ represents a substituted or unsubstituted aromatic hydrocarbon group, and Ar ² and Ar ³ are each independently substituted or unsubstituted monocyclic, non-condensed polycyclic or condensed poly Represents a divalent group of a cyclic aromatic hydrocarbon group. Ar ⁴ represents a divalent group of benzene, thiophene, biphenyl, and anthracene, and these may have a substituent. ]
The polymer may have a substituent on the aromatic ring. From the viewpoint of improving solubility, an alkyl group, an alkoxy group, an alkylthio group, and the like can be given. As the number of carbons in these substituents increases, the solubility will improve, but on the other hand, the carrier mobility will decrease, so select a substituent that will provide the desired properties within the range that does not impair the solubility. It is preferable to do. Examples of suitable substituents in that case include an alkyl group having 1 to 25 carbon atoms, an alkoxy group, and an alkylthio group. More preferable examples include an alkyl group having 2 to 18 carbon atoms, an alkoxy group, and an alkylthio group. A plurality of the same substituents may be introduced, or a plurality of different substituents may be introduced. In addition, these alkyl groups, alkoxy groups and alkylthio groups are further halogen atoms, cyano groups, phenyl groups, hydroxyl groups, carboxyl groups, linear, branched or cyclic alkyl groups having 1 to 12 carbon atoms, alkoxy groups. Or you may contain the phenyl group substituted by the alkylthio group.

  Specific examples of the alkyl group include methyl group, ethyl group, n-propyl group, i-propyl group, t-butyl group, s-butyl group, n-butyl group, i-butyl group, pentyl group, hexyl group, Heptyl, octyl, nonyl, decyl, 3,7-dimethyloctyl, 2-ethylhexyl, trifluoromethyl, 2-cyanoethyl, benzyl, 4-chlorobenzyl, 4-methylbenzyl, A cyclopentyl group, a cyclohexyl group, etc. can be mentioned as an example, As an alkoxy group and an alkylthio group, what made the alkoxy group and the alkylthio group by inserting an oxygen atom or a sulfur atom in the bond position of the said alkyl group is mentioned as an example. .

  The polymer is further improved in solubility in a solvent due to the presence of an alkyl group, an alkoxy group, or an alkylthio group. It is important to improve the solubility of these materials because the manufacturing tolerance of the film wet film forming process is increased. For example, the choice of coating solvent is expanded, the temperature range during solution preparation is expanded, the temperature and pressure range during solvent drying is expanded, and the high processability results in high purity and high uniformity. The possibility of obtaining a high-quality thin film increases.

The substituted or unsubstituted aromatic hydrocarbon group Ar ¹ in the general formula (I) may be a monocyclic group or a polycyclic group (a condensed polycyclic group or a non-condensed polycyclic group). Can be mentioned. Examples include phenyl group, naphthyl group, pyrenyl group, fluorenyl group, azulenyl group, anthryl group, triphenylenyl group, chrycenyl group, biphenyl group, terphenyl group, etc.Substituted or unsubstituted, monocyclic, non-condensed polycyclic Or as condensed polycyclic aromatic hydrocarbon Ar < ² >, Ar < ³ >, the bivalent group of the said aromatic group is mentioned as an example.

Moreover, these aromatic hydrocarbon groups may have a substituent shown below.
(1) Halogen atom, trifluoromethyl group, cyano group, nitro group.
(2) A linear or branched alkyl group or alkoxy group having 1 to 25 carbon atoms. These may be further substituted with a halogen atom, a cyano group, a phenyl group, a hydroxyl group, a carboxyl group, an alkoxy group, or an alkylthio group.
(3) Aryloxy group. (Examples include aryloxy groups having a phenyl group or a naphthyl group as the aryl group. These may contain a halogen atom as a substituent, and are a linear or branched alkyl group or alkoxy having 1 to 25 carbon atoms. A phenoxy group, 1-naphthyloxy group, 2-naphthyloxy group, 4-methylphenoxy group, 4-methoxyphenoxy group, 4-chlorophenoxy group, 6 -A methyl-2-naphthyloxy group etc. are mentioned.
(4) An alkylthio group or an arylthio group. (Specific examples of the alkylthio group or arylthio group include a methylthio group, an ethylthio group, a phenylthio group, and a p-methylphenylthio group.)
(5) An alkyl-substituted amino group. (Specifically, diethylamino group, N-methyl-N-phenylamino group, N, N-diphenylamino group, N, N-di (p-tolyl) amino group, dibenzylamino group, piperidino group, morpholino group And a urolidyl group.)
(6) Acyl group. (Specific examples of the acyl group include an acetyl group, a propionyl group, a butyryl group, a malonyl group, and a benzoyl group.)
Of the polymers containing the repeating unit represented by the general formula (I), a more preferred first embodiment is a polymer containing a repeating unit represented by the following general formula (III).

〔式（ＩＩＩ）中、Ａｒ^１は置換もしくは無置換の芳香族炭化水素基を表し、Ａｒ^４はベンゼン、チオフェン、ビフェニル、アントラセンの２価基を表し、これらは置換基を有していてもよい。Ｒ^７、Ｒ^８はそれぞれ独立にハロゲン原子、置換もしくは無置換の、アルキル基またはアルコキシ基もしくはアルキルチオ基から選択される基を表し、ｘ、ｙはそれぞれ独立に０から４の整数を表し、Ｒ^７、Ｒ^８が各々複数存在する場合には、同一でも別異でもよい。アルキル基またはアルコキシ基もしくはアルキルチオ基への置換基については前記一般式（Ｉ）と同様である。〕
上記一般式（ＩＩＩ）に示される繰り返し単位を含む重合体のうち、さらに好ましい第一の態様は下記一般式（ＩＶ）で表される繰り返し単位を有する重合体である。

[In Formula (III), Ar ¹ represents a substituted or unsubstituted aromatic hydrocarbon group, Ar ⁴ represents a divalent group of benzene, thiophene, biphenyl, and anthracene, and these may have a substituent. Good. R ⁷ and R ⁸ each independently represent a halogen atom, a substituted or unsubstituted alkyl group, an alkoxy group or an alkylthio group, x and y each independently represents an integer of 0 to 4, ⁷ and R ⁸ may be the same or different when there are a plurality of R ^{8 s} . The substituent on the alkyl group, alkoxy group or alkylthio group is the same as in the general formula (I). ]
Of the polymers containing the repeating unit represented by the general formula (III), a more preferred first embodiment is a polymer having a repeating unit represented by the following general formula (IV).

〔式（ＩＶ）中、Ａｒ^４はベンゼン、チオフェン、ビフェニル、アントラセンの２価基を表し、これらは置換基を有していてもよい。Ｒ^７、Ｒ^８はそれぞれ独立にハロゲン原子、置換もしくは無置換の、アルキル基またはアルコキシ基もしくはアルキルチオ基から選択される基を表し、Ｒ^９はハロゲン原子、置換もしくは無置換の、アルキル基、アルコキシ基、アルキルチオ基、アリール基から選択される基を表す。ｚは０から５の整数を表し、ｘ、ｙはそれぞれ独立に０から４の整数を表し、Ｒ^７、Ｒ^８、Ｒ^９が各々複数存在する場合には、同一でも別異でもよい。アルキル基またはアルコキシ基もしくはアルキルチオ基への置換基については前記一般式（Ｉ）と同様である。

[In the formula (IV), Ar ⁴ represents a divalent group of benzene, thiophene, biphenyl, or anthracene, and these may have a substituent. R ⁷ and R ⁸ each independently represent a halogen atom, a substituted or unsubstituted alkyl group, an alkoxy group or an alkylthio group, and R ⁹ represents a halogen atom, a substituted or unsubstituted alkyl group, an alkoxy group Represents a group selected from a group, an alkylthio group, and an aryl group. z represents an integer of 0 to 5, x and y each independently represents an integer of 0 to 4, and when there are a plurality of R ⁷ , R ⁸ and R ⁹ , they may be the same or different. The substituent on the alkyl group, alkoxy group or alkylthio group is the same as in the general formula (I).

  Of the polymers containing the repeating unit represented by the general formula (III), a further preferred second embodiment is a polymer containing a repeating unit represented by the following general formula (V).

〔式（Ｖ）中、Ａｒ^４はベンゼン、チオフェン、ビフェニル、アントラセンの２価基を表し、これらは置換基を有していてもよい。Ｒ^７、Ｒ^８、Ｒ^１０、Ｒ^１１、Ｒ^１２、Ｒ^１３はそれぞれ独立にハロゲン原子、置換もしくは無置換の、アルキル基またはアルコキシ基もしくはアルキルチオ基から選択される基を表す。ｖは０から３の整数を表し、ｗ、ｘ、ｙはそれぞれ独立に０から４の整数を表し、Ｒ^７、Ｒ^８、Ｒ^１０、Ｒ^１１が各々複数存在する場合には、同一でも別異でもよい。アルキル基またはアルコキシ基もしくはアルキルチオ基への置換基については前記一般式（Ｉ）と同様である。〕
上記一般式（Ｉ）に示される繰り返し単位を含む重合体のうち、より好ましい第二の態様は下記一般式（ＶＩ）で表される繰り返し単位を含む重合体である。

[In the formula (V), Ar ⁴ represents a divalent group of benzene, thiophene, biphenyl, or anthracene, and these may have a substituent. R ⁷ , R ⁸ , R ¹⁰ , R ¹¹ , R ¹² , and R ¹³ each independently represent a halogen atom, a substituted or unsubstituted alkyl group, an alkoxy group, or an alkylthio group. v represents an integer of 0 to 3, w, x, and y each independently represents an integer of 0 to 4, and when there are a plurality of R ⁷ , R ⁸ , R ¹⁰ , and R ¹¹ , they may be the same or different. It may be different. The substituent on the alkyl group, alkoxy group or alkylthio group is the same as in the general formula (I). ]
Of the polymers containing a repeating unit represented by the above general formula (I), a more preferred second embodiment is a polymer containing a repeating unit represented by the following general formula (VI).

〔式（ＶＩ）中、Ａｒ^１は置換もしくは無置換の芳香族炭化水素基を表し、Ａｒ^４はベンゼン、チオフェン、ビフェニル、アントラセンの２価基を表し、これらは置換基を有していてもよい。Ｒ^１４、Ｒ^１５、Ｒ^１６、Ｒ^１７ はそれぞれ独立にハロゲン原子、置換もしくは無置換の、アルキル基またはアルコキシ基もしくはアルキルチオ基から選択される基を表し、ｒ、ｓ、ｔ、ｕはそれぞれ独立に０から４の整数を表し、Ｒ^１４、Ｒ^１５、Ｒ^１６、Ｒ^１７が各々複数存在する場合には、同一でも別異でもよい。アルキル基またはアルコキシ基もしくはアルキルチオ基への置換基については前記一般式（Ｉ）と同様である。〕
また、上記一般式（ＶＩ）に示される繰り返し単位を含む重合体のうち、さらに好ましい第一の態様は下記一般式（ＶＩＩ）で表される繰り返し単位を含む重合体である。

[In the formula (VI), Ar ¹ represents a substituted or unsubstituted aromatic hydrocarbon group, Ar ⁴ represents a divalent group of benzene, thiophene, biphenyl, and anthracene, and these may have a substituent. Good. R ¹⁴ , R ¹⁵ , R ¹⁶ and R ¹⁷ each independently represents a halogen atom, a substituted or unsubstituted alkyl group, an alkoxy group or an alkylthio group, and r, s, t and u each independently Represents an integer of 0 to 4, and a plurality of R ¹⁴ , R ¹⁵ , R ¹⁶ and R ¹⁷ may be the same or different. The substituent on the alkyl group, alkoxy group or alkylthio group is the same as in the general formula (I). ]
Of the polymers containing the repeating unit represented by the general formula (VI), a more preferred first embodiment is a polymer containing a repeating unit represented by the following general formula (VII).

〔式（ＶＩＩ）中、Ａｒ^４はベンゼン、チオフェン、ビフェニル、アントラセンの２価基を表し、これらは置換基を有していてもよい。Ｒ^１４、Ｒ^１５、Ｒ^１６、Ｒ^１７、Ｒ^１８はそれぞれ独立にハロゲン原子、置換もしくは無置換の、アルキル基またはアルコキシ基もしくはアルキルチオ基から選択される基を表し、ｑは０から５の整数を表し、ｒ、ｓ、ｔ、ｕはそれぞれ独立に０から４の整数を表し、Ｒ^１４、Ｒ^１５、Ｒ^１６、Ｒ^１７、Ｒ^１８が各々複数存在する場合には、同一でも別異でもよい。アルキル基またはアルコキシ基もしくはアルキルチオ基への置換基については前記一般式（Ｉ）と同様である。〕
上記一般式（Ｉ）に示される繰り返し単位を含む重合体のうち、さらに好ましい具体的態様は下記一般式（ＶＩＩＩ）で表される繰り返し単位を含む重合体である。

[In the formula (VII), Ar ⁴ represents a divalent group of benzene, thiophene, biphenyl, and anthracene, and these may have a substituent. R ¹⁴ , R ¹⁵ , R ¹⁶ , R ¹⁷ and R ¹⁸ each independently represent a halogen atom, a substituted or unsubstituted alkyl group, an alkoxy group or an alkylthio group, and q is an integer of 0 to 5 And r, s, t, and u each independently represent an integer of 0 to 4, and when there are a plurality of R ¹⁴ , R ¹⁵ , R ¹⁶ , R ¹⁷ , and R ¹⁸ , they may be the same or different. Good. The substituent on the alkyl group, alkoxy group or alkylthio group is the same as in the general formula (I). ]
Among the polymers containing the repeating unit represented by the general formula (I), a more preferred specific embodiment is a polymer containing a repeating unit represented by the following general formula (VIII).

〔式（ＶＩＩＩ）中、Ａｒ^１は置換または無置換の芳香族炭化水素基を表し、Ｒ^７、Ｒ^８、Ｒ^１９はそれぞれ独立に水素原子、ハロゲン原子、置換もしくは無置換の、アルキル基またはアルコキシ基もしくはアルキルチオ基から選択される基を表し、ｐ、ｘ、ｙはそれぞれ独立に０から４の整数を表し、Ｒ^７、Ｒ^８、Ｒ^１９が各々複数存在する場合には、同一でも別異でもよい。〕
上記一般式（ＶＩＩＩ）に示される繰り返し単位を含む重合体のうち、より好ましい第一の態様は下記一般式（ＩＸ）で示される繰り返し単位を含む重合体である。

[In the formula (VIII), Ar ¹ represents a substituted or unsubstituted aromatic hydrocarbon group, and R ⁷ , R ⁸ and R ¹⁹ each independently represent a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group or Represents a group selected from an alkoxy group or an alkylthio group, p, x and y each independently represents an integer of 0 to 4, and when there are a plurality of R ⁷ , R ⁸ and R ¹⁹ , they may be the same or different. It may be different. ]
Of the polymers containing a repeating unit represented by the above general formula (VIII), a more preferred first embodiment is a polymer containing a repeating unit represented by the following general formula (IX).

〔式（ＩＸ）中、Ｒ^７、Ｒ^８、Ｒ^１９、Ｒ^２０はそれぞれ独立にハロゲン原子、置換もしくは無置換の、アルキル基またはアルコキシ基もしくはアルキルチオ基から選択される基を表し、ｎは０から５の整数を示し、ｐ、ｘ、ｙはそれぞれ独立に０から４の整数を表し、Ｒ^７、Ｒ^８、Ｒ^１９、Ｒ^２０が各々複数存在する場合には、同一でも別異でもよい。〕
アルキル基またはアルコキシ基もしくはアルキルチオ基への置換基については前記一般式（Ｉ）と同様である。

[In formula (IX), R ⁷ , R ⁸ , R ¹⁹ and R ²⁰ each independently represents a halogen atom, a substituted or unsubstituted alkyl group, an alkoxy group or an alkylthio group, and n is 0 To p, x and y each independently represents an integer from 0 to 4, and when there are a plurality of R ⁷ , R ⁸ , R ¹⁹ and R ²⁰ , they may be the same or different. . ]
The substituent on the alkyl group, alkoxy group or alkylthio group is the same as in the general formula (I).

  Of the polymers containing the repeating unit represented by the general formula (VIII), a more preferred second embodiment is a polymer containing a repeating unit represented by the following general formula (X).

〔式（Ｘ）中、Ｒ^７、Ｒ^８、Ｒ^１９、Ｒ^２１、Ｒ^２２はそれぞれ独立にハロゲン原子、置換もしくは無置換の、アルキル基またはアルコキシ基もしくはアルキルチオ基から選択される基を表し、ｌは０から５の整数を示し、ｍ、ｐ、ｖ、ｘ、ｙはそれぞれ独立に０から４の整数を表し、Ｒ^７、Ｒ^８、Ｒ^１９、Ｒ^２１、Ｒ^２２が各々複数存在する場合には、同一でも別異でもよい。〕
アルキル基またはアルコキシ基もしくはアルキルチオ基への置換基については前記一般式（Ｉ）と同様である。

[In the formula (X), R ⁷ , R ⁸ , R ¹⁹ , R ²¹ and R ²² each independently represents a halogen atom, a substituted or unsubstituted alkyl group, an alkoxy group or an alkylthio group, l represents an integer of 0 to 5, m, p, v, x, and y each independently represents an integer of 0 to 4, and there are a plurality of R ⁷ , R ⁸ , R ¹⁹ , R ²¹ , and R ²² , respectively. In some cases, they may be the same or different. ]
The substituent on the alkyl group, alkoxy group or alkylthio group is the same as in the general formula (I).

  Of the polymers containing a repeating unit represented by the above general formula (VIII), a more preferred third embodiment is a polymer containing a repeating unit represented by the following general formula (XI).

〔式中、Ｒ^７、Ｒ^８、Ｒ^１９、Ｒ^２３、Ｒ^２４、Ｒ^２５、Ｒ^２６はそれぞれ独立にハロゲン原子、置換もしくは無置換で、直鎖または分岐鎖のアルキル基またはアルコキシ基もしくはアルキルチオ基から選択される基を表し、ｊは０から３の整数を示し、ｋ、ｐ、ｘ、ｙはそれぞれ独立に０から４の整数を表し、Ｒ^７、Ｒ^８、Ｒ^１９、Ｒ^２３、Ｒ^２４が各々複数存在する場合には、同一でも別異でもよい。〕
アルキル基またはアルコキシ基もしくはアルキルチオ基への置換基については前記一般式（Ｉ）と同様である。

[Wherein R ⁷ , R ⁸ , R ¹⁹ , R ²³ , R ²⁴ , R ²⁵ , R ²⁶ are each independently a halogen atom, a substituted or unsubstituted, linear or branched alkyl group, alkoxy group or alkylthio Represents a group selected from the group, j represents an integer of 0 to 3, k, p, x, y each independently represents an integer of 0 to 4, R ⁷ , R ⁸ , R ¹⁹ , R ²³ , When a plurality of R ²⁴ are present, they may be the same or different. ]
The substituent on the alkyl group, alkoxy group or alkylthio group is the same as in the general formula (I).

  Below, the specific example of the repeating unit of a polymer represented by general formula (I) in this invention is enumerated. It should be noted that these specific examples are not intended to limit the present invention, nor are they disclosed with the intention of limiting.

上記一般式（Ｉ）、（ＩＩＩ）、（ＩＶ）、（Ｖ）、（ＶＩ）、（ＶＩＩ）、（ＶＩＩＩ）、（ＩＸ）、（Ｘ）、及び（ＸＩ）に示される繰り返し単位を含む重合体の製造方法は、例えばアルデヒドとホスホネートを用いたＷｉｔｔｉｇ−Ｈｏｒｎｅｒ反応、アルデヒドとホスホニウム塩を用いたＷｉｔｔｉｇ反応、ビニル置換体とハロゲン化物を用いたＨｅｃｋ反応、アミンとハロゲン化物を用いたＵｌｌｍａｎｎ反応などを用いることができ、公知の方法により製造可能である。特にＷｉｔｔｉｇ−Ｈｏｒｎｅｒ反応およびＷｉｔｔｉｇ反応は反応操作の簡便さから有効である。

Including repeating units represented by the general formulas (I), (III), (IV), (V), (VI), (VII), (VIII), (IX), (X), and (XI) Polymer production methods include, for example, Wittig-Horner reaction using aldehyde and phosphonate, Wittig reaction using aldehyde and phosphonium salt, Heck reaction using vinyl substituent and halide, Ullmann reaction using amine and halide Etc. can be used and can be manufactured by a known method. In particular, the Wittig-Horner reaction and the Wittig reaction are effective because of the simplicity of the reaction operation.

  As an example, a method for producing a polymer in the present invention using a Wittig-Horner reaction will be described.

  As shown in the following reaction formula, the polymer in the present invention is polymerized by mixing a solution in which the phosphonate ester compound and the aldehyde compound are present stoichiometrically and a base more than twice the molar amount thereof. The reaction proceeds and can be obtained.

本発明のアリールアミン重合体を製造する場合には、例えば、Ａとしてアリールアミン部位、ＢとしてＡｒ^４の組み合わせのモノマーを用いるか、またはＡとしてＡｒ^４、Ｂとしてアリールアミン部位の組み合わせのモノマーを用いればよい。

When producing the arylamine polymer of the present invention, for example, a monomer having a combination of an arylamine moiety as A and an Ar ⁴ as B, or a monomer having a combination of Ar ⁴ as A and an arylamine moiety as B, is used. Use it.

  The dialdehyde compound can be synthesized by various known reactions. For example, the following Vilsmeier reaction,

あるいは、アリールリチウム化合物と、ＤＭＦ、Ｎ−ホルミルモルホリン、Ｎ−ホルミルピペリジン等をはじめとするホルミル化剤との下記反応、

Alternatively, the following reaction between an aryllithium compound and a formylating agent including DMF, N-formylmorpholine, N-formylpiperidine and the like,

あるいは、下記Ｇａｔｔｅｒｍａｎ反応、

Alternatively, the following Gatterman reaction,

あるいは、下記ヒドロキシメチル化合物の各種酸化反応、

Alternatively, various oxidation reactions of the following hydroxymethyl compounds,

等を一例として挙げることができ、これら反応を用いてジアルデヒド化合物を合成することができる。

Can be cited as examples, and dialdehyde compounds can be synthesized using these reactions.

  The phosphonic acid diester compound can also be synthesized by various known reactions, but the following Michaelis-Arbuzov reaction is particularly easy.

（式中、Ｘはハロゲンである。）
なお、本発明で用いられる上記重合体の具体的な製造方法は、特願２００３−３０７５６１号および特願２００３−１８５４０２号にその詳細が記載されている。

(In the formula, X is halogen.)
In addition, the specific manufacturing method of the said polymer used by this invention is described in the details in Japanese Patent Application No. 2003-307561 and Japanese Patent Application No. 2003-185402.

  Heavy compounds having repeating units represented by the above general formulas (I), (III), (IV), (V), (VI), (VII), (VIII), (IX), (X) and (XI) The preferable molecular weight of the coalescence is 1000 to 1000000 in terms of polystyrene-reduced number average molecular weight by GPC, more preferably 2000 to 500000. When the molecular weight is too small, the film forming property such as the generation of cracks is deteriorated and the practicality becomes poor. On the other hand, when the molecular weight is too large, the solubility in a general organic solvent is deteriorated, the viscosity of the solution becomes high and the coating becomes difficult, which also causes a problem in practical use.

  The polymer exhibits good solubility in various common organic solvents such as dichloromethane, tetrahydrofuran, chloroform, toluene, dichlorobenzene and xylene.

  The organic semiconductor material constituting the organic semiconductor layer in the device of the present invention contains a compound represented by the following general formula (II) as the second component.

〔式（ＩＩ）中、ｎは０または１の整数、Ａｒ’は置換もしくは無置換のアリール基を表し、Ｒ^１は水素原子、置換もしくは無置換のアルキル基あるいは置換もしくは無置換のアリール基を表し、Ｒ^２は水素原子、置換もしくは無置換のアルキル基あるいは置換もしくは無置換のアリール基を表し、Ａｒ’とＲ^１は共同で環を形成してもよい。
Ａは９−アントリル基または置換もしくは無置換のカルバゾリル基、下記一般式（１）（２）で示される基を表わす。

[In the formula (II), n represents an integer of 0 or 1, Ar ′ represents a substituted or unsubstituted aryl group, R ¹ represents a hydrogen atom, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group. R ² represents a hydrogen atom, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group, and Ar ′ and R ¹ may form a ring together.
A represents a 9-anthryl group or a substituted or unsubstituted carbazolyl group, a group represented by the following general formulas (1) and (2).

式（１）（２）中、Ｒ^３およびＲ^４は水素原子、アルキル基、アルコキシル基、ハロゲン原子、または下記一般式（３）で示される基を表す。

In formulas (1) and (2), R ³ and R ⁴ represent a hydrogen atom, an alkyl group, an alkoxyl group, a halogen atom, or a group represented by the following general formula (3).

式（３）中、Ｒ^５およびＲ^６は置換もしくは未置換のアルキル基、置換もしくは無置換のアリール基を表し、Ｒ^５およびＲ^６は同一でも異なっていてもよく、Ｒ^５およびＲ^６は互いに結合して環を形成してもよい。

In formula (3), R ⁵ and R ⁶ represent a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, R ⁵ and R ⁶ may be the same or different, and R ⁵ and R ⁶ are They may combine with each other to form a ring.

  Specific examples of the general formula (II) include 4-diphenylaminostilbene, 4-di-p-tolylaminostilbene, 4′-diphenylamino-α-phenylstilbene, 4′-di-p-tolylamino-α-phenyl. Stilbene, 9-styrylanthracene, 3-styryl-9-ethylcarbazole, 1,1-diphenyl-4-diethylaminophenyl-1,3-butadiene, 5- [4- (di-p-tolylamino) benzylidene] -5H- And dibenzo [a, d] cycloheptane, 5- [4- (di-p-tolylamino) benzylidene] -5H-dibenzo [a, d] cycloheptene, and the like. These enumerations show compounds used in the present invention. It is not intended to be limiting or disclosed with the intention of limiting it. Specific examples of the compound represented by the general formula (II) used in the present invention are described in detail in JP-B-2-24864, JP-B-3-39306, and JP-B-4-66023. Has been.

  In order to form the organic semiconductor layer of the present invention, the polymer having the repeating unit represented by the general formula (I) and the compound represented by the general formula (II) are mixed with a suitable solvent such as dichloromethane, tetrahydrofuran, chloroform, A solution having an appropriate concentration is prepared by dissolving or dispersing in toluene, dichlorobenzene, xylene or the like, and a semiconductor thin film can be prepared by a wet film formation method using the solution.

  As a wet film forming method for forming the organic semiconductor layer, it is prepared by a known wet film forming technique such as a spin coating method, a dipping method, a blade coating method, a spray coating method, a casting method, an ink jet method, or a printing method. Can do. For these various film forming methods, an appropriate solvent is selected from the solvent types described above.

  The proportion of the compound represented by the general formula (II) in the organic semiconductor layer is preferably 0.01 to 10,000 parts by weight, preferably 1 with respect to 100 parts by weight of the polymer having the repeating unit represented by the general formula (I). To 1000 parts by weight is preferable, and 5 to 300 parts by weight is more preferable.

  The organic semiconductor material according to the present invention is not substantially oxidized even in air in a solid or solution state.

  In the organic TFT of the present invention, the organic semiconductor material layer formed of the above polymer is sandwiched between the source electrode and the drain electrode in any structure as shown in FIGS. It is supposed to be. The thickness of the organic semiconductor layer is selected so as to form a uniform film (that is, a thin film having no gaps or holes that adversely affect the carrier transport properties of the material). The thickness of the organic semiconductor layer is preferably about 200 nm to about 5 nm, particularly about 100 nm to about 5 nm.

  The organic TFT of the present invention is usually formed on a substrate made of glass, silicon, or plastic. When the device is desired to have flexibility, light weight, and low cost, a plastic substrate is usually used. In the case of the transistor structure illustrated in FIGS. 1A and 1B, a gate electrode can be used by using a conductive substrate.

  The insulating layer is disposed between the gate electrode and the semiconductor layer. Suitable insulating materials are well known to those skilled in the art. For example, inorganic materials such as silicon oxide, silicon nitride, aluminum oxide, aluminum nitride, and titanium oxide, or polyimide, polyvinyl alcohol, polyvinylphenol, polyester, when a flexible, lightweight, and inexpensive device is desired. Examples include polymer compounds such as polyethylene, polyphenylene sulfide, polyparaxylylene, polyacrylonitrile, cyanoethyl pullulan, and various organic materials such as various insulating LB films. Combine two or more of these materials. It may be used. The material is not particularly limited, but a material having low conductivity is preferable.

  There are no particular restrictions on the method for producing these insulating layers, and examples include CVD, plasma CVD, plasma polymerization, vapor deposition, spin coating, dipping, printing, inkjet, and LB. Can also be used. In the case where silicon is used as both a gate electrode and a substrate, silicon oxide obtained by thermal oxidation of silicon is preferable.

  The device of the present invention has three spatially separated electrodes (source, drain, gate electrode). The gate electrode is in contact with the insulating layer. Each electrode is formed on the substrate using well-known conventional techniques.

  The material of the source electrode, drain electrode, and 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, aluminum, Zinc, magnesium, and alloys thereof, conductive metal oxides such as indium and tin oxide, or inorganic and organic semiconductors whose conductivity has been improved by doping, such as silicon single crystal, polysilicon, amorphous silicon, germanium Graphite, polyacetylene, polyparaphenylene, polythiophene, polypyrrole, polyaniline, polythienylene vinylene, polyparaphenylene vinylene, and the like. Of the conductive materials, the source electrode and the drain electrode are preferably connected in ohmic contact with the semiconductor layer.

  Hereinafter, an organic semiconductor material containing as a main component a polymer containing a repeating unit represented by any one of the general formulas (I) and (III) to (XI), and a compound represented by the general formula (II) A method for producing an organic thin film transistor using the above and an organic thin film transistor obtained thereby will be described in detail.

  The organic semiconductor film of the organic thin film transistor of the present invention is formed by a wet method.

  Specifically, an organic semiconductor mainly composed of a polymer having a repeating unit represented by any one of the general formulas (I) and (III) to (XI) and a compound represented by the general formula (II). It can be formed by applying a solution of the material and then drying the solvent.

  The organic semiconductor layer is preferably stacked on a gate insulating film (layer) having a surface energy of 25 mN / m or more and 40 mN / m or less. When the surface energy of the gate insulating film is in the above range, This is preferable from the viewpoints of film formability by spin coating of the layer, threshold voltage characteristics, and the like.

  Here, the surface energy is obtained by the Jisman plot method. The Jisman plot method is a method for obtaining surface energy from a contact angle between a solution and a solid surface, which was performed by Mr. Jisman.

  That is, using various solutions having different surface tensions, the contact angle on the solid surface is measured. Plotting the surface tension on the horizontal axis and the cosine of the contact angle on the vertical axis gives a linear relationship. The horizontal axis (surface tension value) that extrapolates a straight line and gives cos θ = 1 (intersection point) is called the critical surface tension (or limit surface tension) of the solid. Used when quantifying sex).

  In the present invention, this critical surface tension is simply referred to as the surface energy of the solid surface.

  As the wet method, the film may be formed by a known printing method such as spin coating, stencil printing, offset printing, or ink jet printing.

  Spin coating is a method of obtaining a coating film on a substrate using centrifugal force due to rotation.

  This has the following problems.

i) Due to the relative position change between the rotating body (substrate) and the air interface due to the rotation, the solvent is rapidly dried due to the effect of so-called wind, and uniform coating film formation cannot be performed.
Therefore, it is preferable to form a film by a cup spin method.

  ii) The cup spin method is performed by the following steps (1) and (2). (1) The substrate is fixed to the bottom surface of the cup (container), and the coating solution is disposed. (2) Thereafter, the container is sealed (covered), and the whole container is rotated to form a film.

  iii) The advantage of this cup spin is that the relative position of the rotating body and air does not change in the enclosed space and is not affected by the wind. Moreover, the sealed space is saturated with the solvent vapor, and rapid drying can be prevented.

  This cup spin method is particularly preferable for film formation of the organic semiconductor material of the present invention by spin coating.

  There is a relation between the surface roughness of the organic semiconductor film and the transistor performance, and the mobility (transistor material property) improves as the flat and uniform film.

  When the surface roughness and mobility were examined according to various film forming conditions, a flat film having a PV value of 1 nm or less was suitable.

  The surface roughness measurement method (definition) is a method performed by the following steps (1) and (2). (1) Using an operation type probe microscope (AFM), the surface shape is measured in a scanning region of 0.5 μm × 0.5 μm. (2) After the baseline correction, the difference between the maximum height and the minimum height of the scanning region is defined as a PV value (peak to valley), and the flatness of the film is quantified using this value.

  In addition, it has been found that the film flatness is affected by the organic solvent used in the film formation by drying the coating film.

  Properties important as an organic solvent include the following.

・ Solubility with solute ・ Surface tension ・ Viscosity ・ Vapor pressure (boiling point)
When flatness after film formation was measured using various organic solvents, it was found that tetrahydrofuran (THF) gave the flattest film.

  Furthermore, considering the drying process of the solvent, the evaporation state of the solvent can be controlled by using a multi-component solvent rather than a one-component solvent. In the present invention, THF is the main component and the other solvent is the second solvent. Good results can be obtained by adding it as a component.

  Further, the coating film is post-baked to eliminate the solvent remaining in the film. Residual solvent affects semiconductor performance.

  As a positive removal of the residual solvent, there is a heat drying method.

  In the organic semiconductor material of the present invention, it is not preferable to raise the treatment temperature too much because of the relationship between the heating temperature and the mobility, and it is desirable to dry these materials at a treatment temperature of 150 ° C. or less.

  The transistor performance evaluation will be described with reference to FIGS.

  This graph relates to an organic TFT having a mixed sample of polymer A and compound a described later as an organic semiconductor layer.

  The field effect mobility of the organic semiconductor is calculated using the following formula.

I _ds = μC _in W (V _g −V _th ) ² / 2L
(Where Cin is the capacitance per unit area of the gate insulating film, W is the channel width, L is the channel length, Vg is the gate voltage, Ids is the source / drain current, μ is the mobility, and Vth is the gate where the channel begins to form. Threshold voltage.)
Specifically, -20V is applied between the source and drain, and the source / drain current is measured when the gate voltage is subtracted from 10 to -20V.

  The square root of the source / drain current measured under the above conditions is plotted against the gate voltage to perform linear approximation. The gate voltage value at which the square root of the source / drain current in the approximate curve becomes 0 A is defined as Vth (FIG. 3).

  Hereinafter, the present invention will be specifically described based on examples.

  Synthesis Example 1 (Synthesis of Polymer 1)

１００ｍｌ四つ口フラスコに、上記のジアルデヒド０．８５２ｇ（２．７０ｍｍｏｌ）及びジホスホネート１．５２５ｇ（２．７０ｍｍｏｌ）を入れ、窒素置換してテトラヒドロフラン７５ｍｌを加えた。この溶液にカリウムｔ−ブトキシドの１．０ｍｏｌｄｍ^−３テトラヒドロフラン溶液６．７５ｍｌ（６．７５ｍｍｏｌ）を滴下し室温で２時間撹拌した後、ベンジルホスホン酸ジエチル及びベンズアルデヒドを順次加え、さらに２時間撹拌した。酢酸およそ１ｍｌを加えて反応を終了し、溶液を水洗した。溶媒を減圧留去した後テトラヒドロフラン及びメタノールを用いて再沈澱による精製を行ない、重合体１を１．０７ｇ得た。収率７３％。

In a 100 ml four-necked flask, 0.852 g (2.70 mmol) of the dialdehyde and 1.525 g (2.70 mmol) of diphosphonate were placed, and the atmosphere was purged with nitrogen, and 75 ml of tetrahydrofuran was added. To this solution, 6.75 ml (6.75 mmol) of a 1.0 moldm- ³ tetrahydrofuran solution of potassium t-butoxide was added dropwise and stirred at room temperature for 2 hours, and then diethyl benzylphosphonate and benzaldehyde were sequentially added, followed by further stirring for 2 hours. About 1 ml of acetic acid was added to terminate the reaction, and the solution was washed with water. After the solvent was distilled off under reduced pressure, purification by reprecipitation was performed using tetrahydrofuran and methanol to obtain 1.07 g of polymer 1. Yield 73%.

  Elemental analysis value (calculated value); C: 84.25% (84.02%), H: 8.20% (7.93%), N: 2.33% (2.45%).

  The glass transition temperature determined from differential scanning calorimetry was 117 ° C. The number average molecular weight in terms of polystyrene measured by GPC was 8500, and the weight average molecular weight was 20000.

  Synthesis Example 2 (Synthesis of Polymer 2)

合成例１と同様の操作を行ない、上記ジアルデヒド４１９．５ｍｇ（１．００ｍｍｏｌ）及びジホスホネート５６４．５ｍｇ（１．００ｍｍｏｌ）から重合体２を５１８．３ｍｇ得た。収率６２％。

The same operation as in Synthesis Example 1 was performed, and 518.3 mg of Polymer 2 was obtained from 419.5 mg (1.00 mmol) of the dialdehyde and 564.5 mg (1.00 mmol) of the diphosphonate. Yield 62%.

  Elemental analysis value (calculated value); C: 85.18% (85.55%), H: 8.03% (7.63%), N: 2.10% (2.08%).

  The glass transition temperature determined from differential scanning calorimetry was 133 ° C. The number average molecular weight in terms of polystyrene measured by GPC was 39200, and the weight average molecular weight was 116000.

  Synthesis Example 3 (Synthesis of Polymer 3)

合成例１と同様の操作を行ない、上記ジアルデヒド１．００ｇ（２．４０ｍｍｏｌ）及びジホスホネート１．３５ｇ（２．４０ｍｍｏｌ）から重合体３を１．３２ｇ得た。収率８２％。

The same operation as in Synthesis Example 1 was performed to obtain 1.32 g of the polymer 3 from 1.00 g (2.40 mmol) of the dialdehyde and 1.35 g (2.40 mmol) of the diphosphonate. Yield 82%.

  Elemental analysis value (calculated value); C: 85.33% (85.55%), H: 7.86% (7.63%), N: 2.30% (2.08%).

  The glass transition temperature determined from differential scanning calorimetry was 152 ° C. The number average molecular weight in terms of polystyrene measured by GPC was 44400, and the weight average molecular weight was 118,000.

Example 1
A 10 wt% tetrahydrofuran solution of a mixture comprising 90 parts by weight of the following polymer A (weight average molecular weight 109100, number average molecular weight 27100) and 10 parts by weight of the following compound a was prepared. This solution was blade-coated on a PET substrate on which an Al electrode was deposited, and dried at 120 ° C. for 30 minutes to produce a thin film having a thickness of about 10 μm. Further, gold was deposited on the semiconductor film to produce a sandwich cell. Using this cell, the carrier mobility of the organic semiconductor material was measured by the time-of-flight method. The results are shown in FIG.

実施例２
重合体Ａ８０重量部、および化合物ａ２０重量部からなる混合物を用いた以外は実施例１と同様の方法によりキャリア移動度を測定した。結果を図４に示す。

Example 2
Carrier mobility was measured by the same method as in Example 1 except that a mixture consisting of 80 parts by weight of Polymer A and 20 parts by weight of Compound a was used. The results are shown in FIG.

Example 3
Carrier mobility was measured by the same method as in Example 1 except that a mixture consisting of 70 parts by weight of polymer A and 30 parts by weight of compound a was used. The results are shown in FIG.

Example 4
Carrier mobility was measured by the same method as in Example 1 except that a mixture consisting of 60 parts by weight of Polymer A and 40 parts by weight of Compound a was used. The results are shown in FIG.

Example 5
Carrier mobility was measured by the same method as in Example 1 except that a mixture consisting of 50 parts by weight of Polymer A and 50 parts by weight of Compound a was used. The results are shown in FIG.

Comparative Example 1
Carrier mobility was measured by the same method as in Example 1 except that a 10 wt% tetrahydrofuran solution containing only polymer A was used. The results are shown in FIG.

  As is clear from FIG. 4, the mixed samples of polymer A and compound a (Examples 1 to 5) are all in any electric field strength as compared with the sample of only polymer A (Comparative Example 1). Fast carrier mobility was shown. In addition, the sample containing only the compound a has a lower value than that of the polymer A, and it was shown that good characteristics can be obtained by mixing both materials in the present invention.

Example 6
A thin film device having a structure shown in FIG. 1A was manufactured using a mixed material of the polymer A and the compound a. A p-doped silicon substrate surface acting as a gate was thermally oxidized to form an SiO ₂ insulating layer having a thickness of 50 nm, and then only one side of the oxide film was removed, and Al was evaporated on the removed surface to form a gate electrode. Next, an Au / Cr film of a source electrode and a drain electrode was vapor-deposited on the SiO ₂ insulating layer so as to have a channel length of 40 μm and a channel width of 10 mm. Subsequently, a 1.0 wt% toluene solution of a mixed material of polymer A and compound a (60 parts by weight of polymer A and 40 parts by weight of compound a) is spin-coated and dried to form an organic semiconductor having a thickness of about 20 nm. A layer was made.

  The transistor characteristics of the organic TFT thus fabricated are shown in FIG. As is apparent from FIG. 5, the fabricated device showed good transistor characteristics.

  Moreover, the field effect mobility of the organic semiconductor was computed using the following formula.

I _ds = μC _in W (V _g −V _th ) ² / 2L
(Where C _in is the capacitance per unit area of the gate insulating film, W is the channel width, L is the channel length, V _g is the gate voltage, I _ds is the source drain current, μ is the mobility, and V _th is the channel. (This is the threshold voltage of the gate that starts.)
The mobility of the fabricated TFT was a high mobility of 3.01 × 10 ⁻³ (cm ² / Vsec).

The _(ratio of the observed _{I ds} when in the observed _{I ds} and _V g = 0V in the case of _V ds = -20 V in V g = -20 V of _V ds = -20 V) off ratio is 2.6 × It was 10 ⁴ and was an excellent value. As described above, the produced organic TFT showed excellent characteristics.

  In addition, environmental evaluation, that is, (1) evaluation of electrical characteristics immediately after fabrication of the device, and (2) evaluation of electrical characteristics after being left in the atmosphere for one week. The ratio (2) / (1) between the value in (1) and the value in (2) was taken, and this value was evaluated as the fluctuation ratio. As a result, the change rate of the on-current was 1.00, and the change rate of the on-off ratio was 1.00, which was excellent in environmental resistance.

Example 7
A thin film device having a structure shown in FIG. 1B was manufactured using a mixed material of the polymer A and the compound a. A p-doped silicon substrate surface acting as a gate was thermally oxidized to form an SiO ₂ insulating layer having a thickness of 50 nm, and then only one side of the oxide film was removed, and Al was evaporated on the removed surface to form a gate electrode. Next, a 1.0 wt% toluene solution of a mixed material of polymer A and compound a (60 parts by weight of polymer A and 40 parts by weight of compound a) is spin-coated on the insulating layer of SiO ₂ and dried. As a result, an organic semiconductor layer having a thickness of about 20 nm was produced. After drying, Au of a source / drain electrode having a channel length of 40 μm and a channel width of 10 mm was deposited on the organic semiconductor layer.

  The transistor characteristics of the organic TFT produced in this manner were measured. The results were almost the same as in Example 6. The produced organic TFT showed excellent carrier mobility, on / off ratio, and environmental resistance.

Comparative Example 2
A thin film device having the structure shown in FIG. 1A was produced in the same manner as in Example 6 except that only the polymer A was used as the organic semiconductor layer. The transistor characteristics of the produced organic TFT are shown in FIG. The mobility in the produced organic TFT was 1.20 × 10 ⁻⁴ (cm ² / Vsec). The on / off ratio was 1.5 × 10 ³ , which was inferior to Examples 6 and 7.

Comparative Example 3
A thin film device having the structure shown in FIG. 1B was fabricated in the same manner as in Example 7 except that poly-3-hexylthiophene was used as the organic semiconductor layer. The mobility of the produced organic TFT was 7.76 × 10 ⁻⁵ (cm ² / Vsec). Further, since the off current (I _ds when V _g = 0V) is large, the on / off ratio was about 10. The environmental resistance of this device was evaluated in the same manner as in Example 6. As a result, the change rate of the on-current was 0.80 and the change rate of the on-off ratio was 0.62, and the mobility, on-off ratio, and environmental resistance were inferior to those of the present invention.

Example 8
A thin film device having a structure shown in FIG. 1B was manufactured using a mixed material of the polymer A and the compound a. A p-doped silicon substrate surface acting as a gate was thermally oxidized to form an SiO ₂ insulating layer having a thickness of 50 nm, and then only one side of the oxide film was removed, and Al was evaporated on the removed surface to form a gate electrode. Next, 1.0 wt% THF / pxylene (80/20) of a mixed material of polymer A and compound a (60 parts by weight of polymer A and 40 parts by weight of compound a) is formed on the insulating layer of SiO _2. ) A coating solution was prepared with a mixed solution, spin-coated and dried to prepare an organic semiconductor layer having a thickness of 30 nm. After drying, Au of a source / drain electrode having a channel length of 40 μm and a channel width of 10 mm was deposited on the organic semiconductor layer.

  Moreover, the field effect mobility of the organic semiconductor was computed using the following formula.

I _ds = μC _in W (V _g −V _th ) ² / 2L
(However, Cin, W, L, Vg, Ids, μ, and Vth are the same as those defined in Example 6.)
The manufactured TFT operated in a depletion mode, and the mobility was as high as 1.04 × 10 ⁻³ (cm ² / Vs).

  In addition, environmental evaluation, that is, (1) evaluation of electrical characteristics immediately after fabrication of the device, and (2) evaluation of electrical characteristics after being left in the atmosphere for one week. The ratio (2) / (1) between the value in (1) and the value in (2) was taken, and this value was evaluated as the fluctuation ratio. As a result, the change rate of the on-current was 1.00, and the change rate of the on-off ratio was 1.00, which was excellent in environmental resistance.

Example 9
A thin film device having a structure shown in FIG. 1A was manufactured using a mixed material of the polymer A and the compound a. A p-doped silicon substrate surface acting as a gate was thermally oxidized to form an SiO ₂ insulating layer having a thickness of 50 nm, and then only one side of the oxide film was removed, and Al was evaporated on the removed surface to form a gate electrode. Next, an Au / Cr film of a source electrode and a drain electrode was deposited on the SiO ₂ insulating layer so as to have a channel length of 40 μm and a channel width of 10 mm. Subsequently, the coating solution was adjusted with a 1.0 wt% THF / p-xylene (80/20) mixed solution of a mixed material of polymer A and compound a (60 parts by weight of polymer A and 40 parts by weight of compound a). Then, an organic semiconductor layer having a thickness of 30 nm was produced by spin coating and drying.

  The transistor characteristics of the organic TFT produced in this way were measured. The results were almost the same as in Example 8. The produced organic TFT showed excellent characteristics in carrier mobility, on / off ratio, and environmental resistance.

Comparative Example 4
An organic TFT was produced in the same manner as in Example 8 except that only the polymer A was used as the organic semiconductor layer. The mobility in the produced organic TFT was 2.70 × 10 ⁻⁵ (cm ² / Vs), which was inferior to Examples 8 and 9.

A thin film device having the structure shown in FIG. 1A was produced in the same manner as in Example 9 except that poly-3-hexylthiophene was used as the organic semiconductor layer. The mobility of the produced organic TFT was 7.76 × 10 ⁻⁵ (cm ² / Vs). Further, since the off current (I _ds when V _g = 0V) is large, the on / off ratio was about 10. The environmental resistance of this device was evaluated in the same manner as in Example 6. As a result, the change rate of the on-current was 0.80, and the change rate of the on-off ratio was 0.62, which was inferior to that of the present invention in terms of mobility, on-off ratio, and environmental resistance.

Example 10
The gate insulating film was treated with HMDS, and a TFT was fabricated by the method described in Example 8 using a mixed material of polymer A and compound a. However, the organic semiconductor solution was 80% toluene and 20% paraxylene.

The organic TFT thus fabricated operated in the enhancement mode. This is very suitable for transistor driving (result is FIG. 2). The mobility was 3.01 × 10 ⁻³ (cm ² / Vs).

  The appropriate range of surface energy was examined by changing the HMDS treatment time and the subsequent heat treatment temperature, and further using a surface modifier such as octadodecyltrichlorosilane.

  The surface energy was determined from the Dysman plot and evaluated using water, glycerin, formamide, diethylene glycol, and dipropylene glycol as standard test solutions. When the surface energy is lower than 25 mN / m, film formation by spin coating cannot be performed (the coating solution is repelled). When the surface energy exceeds 40 mN / m, the threshold voltage is positive (depletion mode), which is not preferable. The surface energy applied was in the range of 25 mN / m or more and 40 mN / m or less.

It is a schematic diagram of 4 types of structural examples of the organic transistor in this invention. It is a graph for demonstrating the performance evaluation of a transistor. 3 is a graph showing the characteristics of the transistor shown in FIG. 2 by another display method. It is a graph which shows the carrier mobility measured in Examples 1-5 and Comparative Example 1. 6 is a graph showing transistor characteristics of an organic thin film transistor fabricated in Example 6. 5 is a graph showing transistor characteristics of an organic thin film transistor manufactured in Comparative Example 2.

Claims (17)

An organic semiconductor material comprising as a main component a mixture comprising a polymer having a repeating unit represented by the following general formula (I) and a compound represented by the following general formula (II).

[In formula (I), Ar ¹ represents a substituted or unsubstituted aromatic hydrocarbon group, and Ar ² and Ar ³ are each independently substituted or unsubstituted monocyclic, non-condensed polycyclic or condensed poly Represents a divalent group of a cyclic aromatic hydrocarbon group. Ar ⁴ represents a divalent group of benzene, thiophene, biphenyl, and anthracene, and these may have a substituent. ]

[In the formula (II), n represents an integer of 0 or 1, Ar ′ represents a substituted or unsubstituted aryl group, R ¹ represents a hydrogen atom, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group. R ² represents a hydrogen atom, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group, and Ar ′ and R ¹ may form a ring together.
A represents a group represented by the following general formulas (1) and (2), a 9-anthryl group, or a substituted or unsubstituted carbazolyl group.

In formulas (1) and (2), R ³ and R ⁴ represent a hydrogen atom, an alkyl group, an alkoxyl group, a halogen atom, or a group represented by the following general formula (3).

In formula (3), R ⁵ and R ⁶ represent a substituted or unsubstituted alkyl group or a substituted or unsubstituted aryl group, R ⁵ and R ⁶ may be the same or different, and R ⁵ and R ⁶ are They may combine with each other to form a ring. ] The organic semiconductor material according to claim 1, wherein the repeating unit represented by the general formula (I) is a repeating unit represented by the following general formula (III).

[In Formula (III), Ar ¹ represents a substituted or unsubstituted aromatic hydrocarbon group, Ar ⁴ represents a divalent group of benzene, thiophene, biphenyl, and anthracene, and these may have a substituent. Good. R ⁷ and R ⁸ each independently represent a halogen atom, a substituted or unsubstituted alkyl group, an alkoxy group or an alkylthio group, x and y each independently represents an integer of 0 to 4, ⁷ and R ⁸ may be the same or different when there are a plurality of R ^{8 s} . ] The organic semiconductor material according to claim 2, wherein the repeating unit represented by the general formula (III) is a repeating unit represented by the following general formula (IV).

[In the formula (IV), Ar ⁴ represents a divalent group of benzene, thiophene, biphenyl, or anthracene, and these may have a substituent. R ⁷ and R ⁸ each independently represent a halogen atom, a substituted or unsubstituted alkyl group, an alkoxy group or an alkylthio group, and R ⁹ represents a halogen atom, a substituted or unsubstituted alkyl group, an alkoxy group Represents a group selected from a group, an alkylthio group, and an aryl group. x and y each independently represents an integer of 0 to 4, z represents an integer of 0 to 5, and when there are a plurality of R ⁷ , R ⁸ and R ⁹ , they may be the same or different. ] The organic semiconductor material according to claim 2, wherein the repeating unit represented by the general formula (III) is a repeating unit represented by the following general formula (V).

[In the formula (V), Ar ⁴ represents a divalent group of benzene, thiophene, biphenyl, or anthracene, and these may have a substituent. R ⁷ , R ⁸ , R ¹⁰ , R ¹¹ , R ¹² , and R ¹³ each independently represent a halogen atom, a substituted or unsubstituted alkyl group, an alkoxy group, or an alkylthio group. v represents an integer of 0 to 3, w, x, and y each independently represents an integer of 0 to 4, and when there are a plurality of R ⁷ , R ⁸ , R ¹⁰ , and R ¹¹ , they may be the same or different. It may be different. ] The organic semiconductor material according to claim 1, wherein the repeating unit represented by the general formula (I) is a repeating unit represented by the following general formula (VI).

[In the formula (VI), Ar ¹ represents a substituted or unsubstituted aromatic hydrocarbon group, Ar ⁴ represents a divalent group of benzene, thiophene, biphenyl, and anthracene, and these may have a substituent. Good. R ¹⁴ , R ¹⁵ , R ¹⁶ and R ¹⁷ each independently represents a halogen atom, a substituted or unsubstituted alkyl group, an alkoxy group or an alkylthio group, and r, s, t and u each independently Represents an integer of 0 to 4, and a plurality of R ¹⁴ , R ¹⁵ , R ¹⁶ and R ¹⁷ may be the same or different. ] The organic semiconductor material according to claim 5, wherein the repeating unit represented by the general formula (VI) is a repeating unit represented by the following general formula (VII).

[In the formula (VII), Ar ⁴ represents a divalent group of benzene, thiophene, biphenyl, or anthracene, and these may have a substituent. R ¹⁴ , R ¹⁵ , R ¹⁶ , R ¹⁷ and R ¹⁸ each independently represent a halogen atom, a substituted or unsubstituted alkyl group, an alkoxy group or an alkylthio group, and q is an integer of 0 to 5 And r, s, t, and u each independently represent an integer of 0 to 4, and when there are a plurality of R ¹⁴ , R ¹⁵ , R ¹⁶ , R ¹⁷ , and R ¹⁸ , they may be the same or different. Good. ] The organic semiconductor material according to claim 1, wherein the repeating unit represented by the general formula (I) is a repeating unit represented by the following general formula (VIII).

[In the formula (VIII), Ar ¹ represents a substituted or unsubstituted aromatic hydrocarbon group, and R ⁷ , R ⁸ and R ¹⁹ each independently represent a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group or Represents a group selected from an alkoxy group or an alkylthio group, p, x and y each independently represents an integer of 0 to 4, and when there are a plurality of R ⁷ , R ⁸ and R ¹⁹ , they may be the same or different. It may be different. ] The organic semiconductor material according to claim 7, wherein the repeating unit represented by the general formula (VIII) is a repeating unit represented by the following general formula (IX).

[In formula (IX), R ⁷ , R ⁸ , R ¹⁹ and R ²⁰ each independently represents a halogen atom, a substituted or unsubstituted alkyl group, an alkoxy group or an alkylthio group, and n is 0 To p, x and y each independently represents an integer of 0 to 4, and when there are a plurality of R ⁷ , R ⁸ , R ¹⁹ and R ²⁰ , they may be the same or different. . ] The organic semiconductor material according to claim 7, wherein the repeating unit represented by the general formula (VIII) is a repeating unit represented by the following general formula (X).

[In the formula (X), R ⁷ , R ⁸ , R ¹⁹ , R ²¹ and R ²² each independently represents a halogen atom, a substituted or unsubstituted alkyl group, an alkoxy group or an alkylthio group, l represents an integer of 0 to 5, m, p, v, x and y each independently represents an integer of 0 to 4, and there are a plurality of R ⁷ , R ⁸ , R ¹⁹ , R ²¹ and R ²² , respectively. In some cases, they may be the same or different. ] The organic semiconductor material according to claim 7, wherein the repeating unit represented by the general formula (VIII) is a repeating unit represented by the following general formula (XI).

[Wherein R ⁷ , R ⁸ , R ¹⁹ , R ²³ , R ²⁴ , R ²⁵ , R ²⁶ are each independently a halogen atom, a substituted or unsubstituted, linear or branched alkyl group, an alkoxy group or an alkylthio group. Represents a group selected from the group, j represents an integer of 0 to 3, k, p, x, y each independently represents an integer of 0 to 4, R ⁷ , R ⁸ , R ¹⁹ , R ²³ , When a plurality of R ²⁴ are present, they may be the same or different. ]   In the repeating unit represented by the general formula (I), (III), (IV), (V), (VI), (VII), (VIII), (IX), (X), or (XI), 11. The repeating unit according to claim 1, wherein the repeating unit has at least one substituted or unsubstituted linear or branched alkyl group, alkoxy group or alkylthio group having 2 to 18 carbon atoms. Organic semiconductor material.   It consists of the organic-semiconductor material in any one of Claims 1-10, the structure which provides the electrode which makes the pair for flowing an electric current through this organic-semiconductor material, and a 3rd electrode, It is characterized by the above-mentioned. Organic thin film transistor.   13. The organic thin film transistor according to claim 12, wherein the third electrode is provided on the structure via an insulator.   General formula (I), (III), (IV), (V), (VI), (VII), (VIII), (IX), (X), or After applying a solution of an organic semiconductor material composed mainly of a mixture comprising a polymer having a repeating unit represented by (XI) and a compound represented by formula (II) according to claim 1, the solvent is dried. A method for producing an organic thin film transistor, comprising the step of forming an organic semiconductor layer.   The method of manufacturing an organic thin film transistor according to claim 14, wherein the organic semiconductor layer is laminated on a gate insulating film having a surface energy of 25 mN / m or more and 40 mN / m or less.   The method of manufacturing an organic thin film transistor according to claim 15, wherein the gate insulating film is surface-modified by silane coupling treatment.   An organic thin film transistor obtained by the production method according to claim 14.

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