JP6572473B2 - Organic compounds and their uses - Google Patents

Description

  The present invention relates to a novel organic compound useful as an organic semiconductor material and use thereof. More specifically, the present invention relates to a specific organic compound useful as an organic semiconductor material, and an organic semiconductor material, an organic thin film, a thin film transistor element, an organic photoelectric conversion element, an organic solar cell, and an organic EL (electroluminescence) using the organic compound. The present invention relates to an organic electronic device such as an element, an organic light emitting transistor element, or an organic semiconductor laser element.

  In recent years, interest in organic electronics devices has increased. As its characteristics, unlike conventional inorganic electronic devices using amorphous silicon or polycrystalline silicon, the device itself has flexibility, and the device can have a large area. Further, according to a film forming method known as a method for manufacturing an organic electronic device, such as a vacuum deposition method or a coating method, it is possible to suppress an increase in manufacturing cost, and further, a process required at the time of film forming Since the temperature can be made relatively low, there is an advantage that the range of selection of materials used for the substrate is widened, and research reports have been actively made for its practical use.

  Typical organic electronic devices include organic EL elements, organic solar cell elements, organic photoelectric conversion elements, organic (thin film) transistor elements, and the like. Organic EL elements are expected as main targets for next-generation display applications as flat panel displays, and are applied to mobile phone displays, TVs (TV receivers), etc., and development aimed at further enhancement of functionality continues. . Organic solar cell elements and the like have been researched and developed for inexpensive energy sources, and organic transistor elements have been studied for the purpose of application to flexible displays and inexpensive ICs (integrated circuits).

  In these organic electronic devices, it is very important to develop semiconductor materials constituting the devices. For example, as a low molecular weight semiconductor material (organic transistor material), acene-based organic semiconductor compounds such as pentacene are actively used. It is being considered. As heteroacene compounds having a heterocyclic ring, materials mainly containing atoms such as sulfur and selenium have been studied. Specific examples of such heteroacene compounds include benzodithiophene compounds (2,6-diphenylbenzo [1,2-b: 4,5-b ′] dithiophenes described in Patent Document 1 and Non-Patent Document 1). (DPh-BDT)), naphthodithiophene compounds (NDT) described in Patent Document 2 and Non-patent Document 4, benzothienobenzothiophene compounds (2,7-diphenyl described in Patent Document 3 and Non-Patent Document 2) [1] benzothieno [3,2-b] [1] benzothiophene (DPh-BTBT), 2,7-dialkyl [1] benzothieno [3,2-b] [ 1] benzothiophene (AlkylBTBT)), dinaphthothienothiophene compound (dinaphtho [2,3-b: 2 ′, 3′-f] thie described in Patent Document 5 and Non-Patent Document 5) Examples include [2,3-b: 2 ′, 3′-f] thieno [2,3-b] thiophene (AlkylDNTT), and other high-performance materials that are stable in the air. Among the unsubstituted heteroacene-based compounds, compounds having better semiconductor properties and atmospheric stability than pentacene have been developed, such as bisbenzothienonaphthodithiophene (BBTNDT), which has the highest mobility. However, there is still nothing satisfying market demand, and there is a demand for the development of semiconductor materials useful for various devices with high mobility and atmospheric stability.

JP 2005-154371 A International Publication No. 2010/058692 International Publication No. 2006/077788 International Publication No. 2008/047896 International Publication No. 2008/050726 International Publication No. 2014/027581

“Journal of the American Chemical Society” (USA), 2004, No. 126, p. 5084-5085 “Journal of the American Chemical Society” (USA), 2006, No. 128, p. 12604-12605 “Journal of the American Chemical Society” (USA), 2007, No. 129, p. 15732-15733 “Journal of the American Chemical Society” (USA), 2011, No. 133, p. 5024-5035 “Journal of the American Chemical Society” (USA), 2007, No. 129, p. 2224-2225

  An object of the present invention is to provide a novel organic compound that can be used in an organic electronic device, and more specifically, to an organic electronic device such as an organic EL element, an organic solar cell element, an organic transistor element, and an organic semiconductor laser element. The object is to provide a novel organic compound that can be applied.

（式中、Ｒ^１乃至Ｒ^１６はそれぞれ独立に、水素原子、置換若しくは無置換のアリール基、置換若しくは無置換のアルキル基、ハロゲン原子、置換若しくは無置換のアルコキシ基、置換若しくは無置換のアルキルチオ基、置換若しくは無置換のアルキルアミノ基、置換若しくは無置換のジアルキルアミノ基（アルキル基は互いに結合して窒素原子を含む環状構造を形成してもよい）、置換若しくは無置換のアルキルスルホニル基、置換若しくは無置換のトリアルキルシリル基、置換若しくは無置換のトリアルキルシリルエチニル基、置換若しくは無置換のアリールアミノ基、置換若しくは無置換のジアリールアミノ基、又はシアノ基を表す。）
で表される有機化合物、
［２］前項［１］に記載の有機化合物であって、Ｒ^１乃至Ｒ^４及びＲ^９乃至Ｒ^１２がそれぞれ独立に、水素原子、置換若しくは無置換のアリール基、又は置換若しくは無置換のアルキル基であり、Ｒ^５乃至Ｒ^８及びＲ^１３乃至Ｒ^１６が水素原子である有機化合物、
［３］前項［２］に記載の有機化合物であって、Ｒ^１乃至Ｒ^４及びＲ^９乃至Ｒ^１２がそれぞれ独立に水素原子又は置換若しくは無置換のアルキル基である有機化合物、
［４］前項［３］に記載の有機化合物であって、Ｒ^１乃至Ｒ^４及びＲ^９乃至Ｒ^１２がそれぞれ独立に水素原子又は炭素数１乃至３の無置換のアルキル基である有機化合物、
［５］前項［４］に記載の有機化合物であって、Ｒ^１乃至Ｒ^４及びＲ^９乃至Ｒ^１２が水素原子である有機化合物、
［６］前項［４］に記載の有機化合物であって、
Ｒ^２及びＲ^１０の一方が炭素数１乃至３の無置換のアルキル基であって他方が水素原子又は炭素数１乃至３の無置換のアルキル基であり、かつＲ^１、Ｒ^３、Ｒ^４、Ｒ^９、Ｒ^１１及びＲ^１２が水素原子であるか、若しくは
Ｒ^３及びＲ^１１の一方が炭素数１乃至３の無置換のアルキル基であって他方が水素原子又は炭素数１乃至３の無置換のアルキル基であり、かつＲ^１、Ｒ^２、Ｒ^４、Ｒ^９、Ｒ^１０及びＲ^１２が水素原子である有機化合物、
［７］前項［１］乃至［６］の何れか一項に記載の有機化合物を含有する有機半導体材料、
［８］前項［７］に記載の有機半導体材料からなる有機薄膜、
［９］前項［７］に記載の有機半導体材料を含む有機エレクトロニクスデバイス、
［１０］前項［９］に記載の有機エレクトロニクスデバイスであって、薄膜トランジスタ素子、有機光電変換素子、有機太陽電池素子、有機ＥＬ素子、有機発光トランジスタ素子、又は有機半導体レーザー素子である有機エレクトロニクスデバイス、
［１１］前項［１０］に記載の有機エレクトロニクスデバイスであって、薄膜トランジスタ素子、有機光電変換素子、又は有機太陽電池素子である有機エレクトロニクスデバイス、
［１２］前項［１０］又は［１１］に記載の有機エレクトロニクスデバイスであって、薄膜トランジスタ素子である有機エレクトロニクスデバイス。 As a result of studying various organic compounds, the present inventors have found that the above problems can be solved by using an organic compound having a specific structure, and have completed the present invention.
That is, the present invention is as follows.
[1] The following formula (1)

Wherein R ^{1 to} R ¹⁶ are each independently a hydrogen atom, a substituted or unsubstituted aryl group, a substituted or unsubstituted alkyl group, a halogen atom, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted alkylthio; A group, a substituted or unsubstituted alkylamino group, a substituted or unsubstituted dialkylamino group (the alkyl groups may be bonded to each other to form a cyclic structure containing a nitrogen atom), a substituted or unsubstituted alkylsulfonyl group, A substituted or unsubstituted trialkylsilyl group, a substituted or unsubstituted trialkylsilylethynyl group, a substituted or unsubstituted arylamino group, a substituted or unsubstituted diarylamino group, or a cyano group.
An organic compound represented by
[2] The organic compound according to [1], wherein R ^{1 to} R ⁴ and R ^{9 to} R ¹² are each independently a hydrogen atom, a substituted or unsubstituted aryl group, or a substituted or unsubstituted alkyl An organic compound in which R ^{5 to} R ⁸ and R ^{13 to} R ¹⁶ are hydrogen atoms,
[3] The organic compound according to [2], wherein R ^{1 to} R ⁴ and R ^{9 to} R ¹² are each independently a hydrogen atom or a substituted or unsubstituted alkyl group,
[4] The organic compound according to [3], wherein R ^{1 to} R ⁴ and R ^{9 to} R ¹² are each independently a hydrogen atom or an unsubstituted alkyl group having 1 to 3 carbon atoms,
[5] The organic compound according to [4], wherein R ^{1 to} R ⁴ and R ^{9 to} R ¹² are hydrogen atoms,
[6] The organic compound according to [4] above,
One of R ² and R ¹⁰ is an unsubstituted alkyl group having 1 to 3 carbon atoms, the other is a hydrogen atom or an unsubstituted alkyl group having 1 to 3 carbon atoms, and R ¹ , R ³ , R ⁴ , R ⁹ , R ¹¹ and R ¹² are hydrogen atoms, or one of R ³ and R ¹¹ is an unsubstituted alkyl group having 1 to 3 carbon atoms and the other is a hydrogen atom or 1 to 3 carbon atoms An organic compound which is an unsubstituted alkyl group and R ¹ , R ² , R ⁴ , R ⁹ , R ¹⁰ and R ¹² are hydrogen atoms,
[7] An organic semiconductor material containing the organic compound according to any one of [1] to [6],
[8] An organic thin film comprising the organic semiconductor material according to [7] above,
[9] An organic electronic device comprising the organic semiconductor material according to [7] above,
[10] The organic electronic device according to [9], wherein the organic electronic device is a thin film transistor element, an organic photoelectric conversion element, an organic solar cell element, an organic EL element, an organic light emitting transistor element, or an organic semiconductor laser element.
[11] The organic electronic device according to [10], wherein the organic electronic device is a thin film transistor element, an organic photoelectric conversion element, or an organic solar cell element.
[12] The organic electronic device according to [10] or [11], which is a thin film transistor element.

  ADVANTAGE OF THE INVENTION According to this invention, the novel organic compound which can be used for an organic electronics device can be provided. Furthermore, according to the present invention, by using a novel organic compound as an organic semiconductor material, an organic electronic device having excellent semiconductor characteristics such as threshold voltage, carrier mobility, on / off ratio and the like, and having high atmospheric stability can be obtained. Can be provided.

BRIEF DESCRIPTION OF THE DRAWINGS It is a schematic sectional drawing which shows some example of a structure of the thin-film transistor element of this invention, (a) is a bottom contact-bottom gate type thin-film transistor element, (b) is a top contact-bottom gate type thin-film transistor element, (c). Is a top contact-top gate type thin film transistor element, (d) is a top & bottom gate type thin film transistor element, (e) is an electrostatic induction transistor element, and (f) is a bottom contact-top gate type thin film transistor element. It is explanatory drawing for demonstrating the manufacturing process of the top contact-bottom gate type thin-film transistor element as an example of the thin-film transistor element of this invention, (a)-(f) is a schematic sectional drawing which shows each manufacturing process. . It is a schematic sectional drawing which shows an example of the structure of the organic solar cell element as one aspect | mode of the organic electronics device of this invention. 2 is a graph showing an ultraviolet-visible absorption spectrum of a thin film made of an organic compound represented by formula (11) obtained in Example 1. FIG. It is a graph which shows the transfer characteristic immediately after preparation of the thin-film transistor element obtained in Example 2, and one month later. It is a graph which shows the transmission characteristic of the thin film transistor element obtained by the comparative example 1 immediately after preparation and one month later.

で表される。 The present invention is described in detail below.
[Organic compounds]
The organic compound of the present invention has the following formula (1)

It is represented by

In formula (1), R ^{1 to} R ¹⁶ are each independently a hydrogen atom, a substituted or unsubstituted aryl group, a substituted or unsubstituted alkyl group, a halogen atom, a substituted or unsubstituted alkoxy group, substituted or unsubstituted Alkylthio group, substituted or unsubstituted alkylamino group, substituted or unsubstituted dialkylamino group (two alkyl groups may be bonded to each other to form a cyclic structure containing a nitrogen atom), substituted or unsubstituted It represents an alkylsulfonyl group, a substituted or unsubstituted trialkylsilyl group, a substituted or unsubstituted trialkylsilylethynyl group, a substituted or unsubstituted arylamino group, a substituted or unsubstituted diarylamino group, or a cyano group. Here, “substituted” means that at least one hydrogen atom of the base group (eg, alkyl group) is substituted with a substituent, and “unsubstituted” means that the base group is not substituted. It means that the hydrogen atom of the group is not substituted with a substituent. Therefore, for example, the term “unsubstituted alkyl group” as used herein means an alkyl group in which a hydrogen atom on the alkyl group is not substituted with a substituent, that is, a saturated hydrocarbon group consisting of only a carbon atom and a hydrogen atom. To do.

Examples of the substituted or unsubstituted aryl group represented by R ^{1 to} R ^{16 in} the formula (1) include aromatic hydrocarbon groups such as a phenyl group, a naphthyl group, an anthryl group, a phenanthryl group, a pyrenyl group, and a benzopyrenyl group; Group, pyrazyl group, pyrimidyl group, quinolyl group, isoquinolyl group, pyrrolyl group, indolenyl group, imidazolyl group, carbazolyl group, thienyl group, furyl group, pyranyl group, pyridonyl group and other heterocyclic groups; benzoquinolyl group, anthraquinolyl group, benzo Examples thereof include condensed heterocyclic groups such as thienyl group and benzofuryl group. Among these, a phenyl group, a naphthyl group, a pyridyl group, and a thienyl group are preferable, and a phenyl group is particularly preferable. The substituted or unsubstituted aryl group preferably has 3 to 60 carbon atoms.

In the case where R ^{1 to} R ^{16 in} Formula (1) represent a substituted aryl group, the substituent that the substituted aryl group has is not particularly limited, and examples thereof include a halogen atom, a substituted or unsubstituted alkyl group, and the like. Is mentioned. Examples of the substituted or unsubstituted alkyl group as the substituent of the substituted aryl group include the groups listed below as examples of the substituted or unsubstituted alkyl group represented by R ^{1 to} R ¹⁶ in Formula (1). . Examples of the halogen atom as a substituent that the substituted aryl group has include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. Of these, the substituted aryl group preferably has a substituted or unsubstituted alkyl group having 1 to 3 carbon atoms.

Examples of the substituted or unsubstituted alkyl group represented by R ^{1 to} R ^{16 in} Formula (1) include a substituted or unsubstituted saturated or unsaturated linear, branched, or cyclic alkyl group. The substituted or unsubstituted alkyl group preferably has 1 to 20 carbon atoms. Here, as the unsubstituted saturated or unsaturated linear or branched alkyl group, for example, methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, allyl group, t -Butyl group, n-pentyl group, n-hexyl group, n-octyl group, n-decyl group, n-dodecyl group, n-stearyl group, n-butenyl group and the like can be mentioned. In addition, examples of the unsubstituted cyclic alkyl group include cycloalkyl groups having 3 to 12 carbon atoms such as a cyclohexyl group, a cyclopentyl group, an adamantyl group, and a norbornyl group.

In the case where R ^{1 to} R ^{16 in} Formula (1) represent a substituted alkyl group, the substituent that the substituted alkyl group has is not particularly limited, and examples thereof include a halogen atom, a substituted or unsubstituted aryl group, and the like. Is mentioned. Examples of the substituted or unsubstituted aryl group as the substituent of the substituted alkyl group include the groups listed above as examples of the substituted or unsubstituted aryl group represented by R ^{1 to} R ¹⁶ in Formula (1). It is done. Examples of the halogen atom as a substituent that the substituted alkyl group has include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.

  Examples of the substituted alkyl group having a halogen atom as a substituent (haloalkyl group) include a chloromethyl group, 1-chloroethyl group, 2-chloroethyl group, 2-chloroisobutyl group, 1,2-dichloroethyl group, 1, 3-dichloroisopropyl group, 2,3-dichloro-t-butyl group, 1,2,3-trichloropropyl group, bromomethyl group, 1-bromoethyl group, 2-bromoethyl group, 2-bromoisobutyl group, 1,2- Dibromoethyl group, 1,3-dibromoisopropyl group, 2,3-dibromo-t-butyl group, 1,2,3-tribromopropyl group, iodomethyl group, 1-iodoethyl group, 2-iodoethyl group, 2-iodo Isobutyl group, 1,2-diiodoethyl group, 1,3-diiodoisopropyl group, 2,3-diiodo-t-butyl group, 1, , 3-triiodopropyl group, fluoromethyl group, 1-fluoroethyl group, 2-fluoroethyl group, 2-fluoroisobutyl group, 1,2-difluoroethyl group, difluoromethyl group, trifluoromethyl group, pentafluoroethyl group , Perfluoroisopropyl group, perfluorobutyl group, perfluorocyclohexyl group and the like.

  The substituted or unsubstituted alkyl group is preferably a substituted or unsubstituted saturated linear alkyl group, more preferably a substituted or unsubstituted saturated linear alkyl group having 1 to 3 carbon atoms, An unsubstituted saturated linear alkyl group having 1 to 3 carbon atoms is preferred. The substituted or unsubstituted alkyl group is preferably a substituted or unsubstituted alkyl group having 1 to 3 carbon atoms, and more preferably an unsubstituted alkyl group having 1 to 3 carbon atoms.

Examples of the halogen atom represented by the formula (1) R ^{1 to} R ¹⁶ include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.

The substituted or unsubstituted alkoxy group is a group represented by —OZ ¹ (Z ¹ represents the above-described substituted or unsubstituted alkyl group). Examples of Z ¹ include the above-described substituted or unsubstituted groups. Each group mentioned as an example of the alkyl group of is mentioned.

The substituted or unsubstituted alkylthio group is a group represented by —SZ ¹ (Z ¹ represents the above-described substituted or unsubstituted alkyl group), and examples of Z ¹ include the above-described substituted or unsubstituted group. Each group mentioned as an example of the alkyl group of is mentioned.

The substituted or unsubstituted alkylamino group is a group represented by —NHZ ¹ (Z ¹ represents the above-described substituted or unsubstituted alkyl group). The substituted or unsubstituted dialkylamino group is a group represented by —NZ ¹ Z ² (Z ¹ and Z ² each independently represents the above-described substituted or unsubstituted alkyl group). In these alkylamino groups and dialkylamino groups, examples of Z ¹ and Z ² include the groups listed as examples of the substituted or unsubstituted alkyl group described above. The two alkyl groups of the dialkylamino group may be bonded to each other to form a ring structure containing a nitrogen atom. Examples of the ring structure include a pyrrolidine ring and a piperidine ring.

The substituted or unsubstituted alkylsulfonyl group is a group represented by —SO ₂ Z ¹ (Z ¹ represents the above-described substituted or unsubstituted alkyl group), and examples of Z ¹ include the above-mentioned substituted Or each group mentioned as an example of an unsubstituted alkyl group is mentioned.

The substituted or unsubstituted trialkylsilyl group is represented by —SiZ ¹ Z ² Z ³ (Z ¹ , Z ² , and Z ³ each independently represents the above-described substituted or unsubstituted alkyl group). It is a group. Examples of Z ¹ , Z ² , and Z ³ include the groups listed as examples of the substituted or unsubstituted alkyl group described above. Examples of the substituted or unsubstituted trialkylsilyl group include a trimethylsilyl group.

The substituted or unsubstituted trialkylsilylethynyl group is —C≡C—SiZ ¹ Z ² Z ³ (Z ¹ , Z ² and Z ³ each independently represents the above-mentioned substituted or unsubstituted alkyl group. ). Examples of Z ¹ , Z ² , and Z ³ include the groups listed as examples of the substituted or unsubstituted alkyl group described above. Examples of the substituted or unsubstituted trialkylsilylethynyl group include a trimethylsilylethynyl group, a triethylsilylethynyl group, a triisopropylsilylethynyl group, and the like.

The arylamino group is a group represented by —NHZ ⁴ (Z ⁴ represents the above-described substituted or unsubstituted aryl group). The diarylamino group is a group represented by —NZ ⁵ Z ⁶ (Z ⁵ and Z ⁶ each independently represents the above-described substituted or unsubstituted aryl group). Examples of Z ₅ and Z ₆ include the groups listed as examples of the substituted or unsubstituted aryl group described above.

（式中、Ｒ^１乃至Ｒ^４及びＲ^９乃至Ｒ^１２はそれぞれ独立に、水素原子、置換若しくは無置換のアリール基、又は置換若しくは無置換のアルキル基を表す） Among the organic compounds represented by the formula (1), R ^{1 to} R ⁴ and R ^{9 to} R ¹² are each independently a hydrogen atom, a substituted or unsubstituted aryl group, or a substituted or unsubstituted alkyl group. , R ^{5 to} R ⁸ and R ^{13 to} R ¹⁶ are each a hydrogen atom, that is, an organic compound represented by the following formula (1-1) is preferable.

(Wherein R ^{1 to} R ⁴ and R ^{9 to} R ¹² each independently represent a hydrogen atom, a substituted or unsubstituted aryl group, or a substituted or unsubstituted alkyl group)

R ^{1 to} R ⁴ and R ^{9 to} R ¹² in the formula (1-1) are preferably each independently a hydrogen atom or a substituted or unsubstituted alkyl group, and each independently represents a hydrogen atom or 1 to 3 carbon atoms. The unsubstituted alkyl group is more preferable, and it is more preferable that all of R ^{1 to} R ⁴ and R ^{9 to} R ¹² are hydrogen atoms.

  When the organic compound represented by the formula (1) of the present invention is used in an organic electronic device, for example, a thin film transistor element, among the organic compounds represented by the formula (1), the following formulas (1-2) and (1-3) By forming an organic thin film using an organic compound having a molecular structure closer to a rod shape, the organic compound represented by the formula (1) has a condensed ring structure (six benzene rings and A high mobility is achieved by arranging the π-conjugated plane of the structural portion in which four thiophene rings are condensed to form a highly efficient crystal structure for charge transport.

（式中、Ｒ^２、Ｒ^３、Ｒ^１０及びＲ^１１はそれぞれ独立に、水素原子、置換若しくは無置換のアリール基、又は置換若しくは無置換のアルキル基を表す）

(Wherein R ² , R ³ , R ¹⁰ and R ¹¹ each independently represents a hydrogen atom, a substituted or unsubstituted aryl group, or a substituted or unsubstituted alkyl group)

That is, as the organic compound represented by the formula (1), the organic compound represented by the above formula (1-2) (in the organic compound represented by the formula (1), R ¹ , R ^{3 to} R ⁹ , And an organic compound in which R ^{11 to} R ¹⁶ are hydrogen atoms) and an organic compound represented by the above formula (1-3) (in the organic compound represented by the formula (1), R ¹ , R ² , R ⁴ To R ¹⁰ , and organic compounds in which R ^{12 to} R ¹⁶ are hydrogen atoms) are preferable. Furthermore, among the organic compound represented by Formula (1-2) and the organic compound represented by Formula (1-3), R ² and R ¹⁰ in Formula (1-2) are each independently a hydrogen atom or Organic compounds that are substituted or unsubstituted alkyl groups and organic compounds in which R ³ and R ¹¹ in formula (1-3) are each independently a hydrogen atom or a substituted or unsubstituted alkyl group are preferred, 2) R ² and R ¹⁰ are each independently a hydrogen atom or an unsubstituted alkyl group having 1 to 3 carbon atoms, and R ³ and R ¹¹ in formula (1-3) are each independently a hydrogen atom. Alternatively, an organic compound that is an unsubstituted alkyl group having 1 to 3 carbon atoms is more preferable. In the formula (1-2), an organic compound in which R ² and R ¹⁰ are hydrogen atoms, and a formula (1-3) An organic compound in which R ³ and R ¹¹ are hydrogen atoms is more preferable. In addition, one of R ² and R ¹⁰ in Formula (1-2) is an aryl group and the other is an aryl group or a hydrogen atom, and one of R ³ and R ¹¹ in Formula (1-3) is aryl. Organic compounds in which the other is an aryl group or a hydrogen atom are also preferred.

  The organic compound represented by the formula (1) of the present invention is obtained, for example, in the following reaction step. In the following reaction step, first, an intermediate compound represented by the formula (2) (see Patent Document 2) is reacted with a tin compound to obtain an intermediate compound represented by the formula (3). Further, a ring-closing precursor represented by the formula (6) is synthesized by a Still coupling reaction between the intermediate compound represented by the formula (3) and the triflated benzene derivative represented by the formula (4) and the formula (5). To do. The target organic compound represented by the formula (1) can be obtained by carrying out the intramolecular cyclization and demethylation reaction of this ring-closing precursor.

  The purification method of the organic compound represented by the formula (1) is not particularly limited, and known methods such as recrystallization, column chromatography, and vacuum sublimation purification can be employed. Moreover, you may use these methods in combination as needed.

  Specific examples of the organic compound represented by the formula (1) are described below, but the present invention is not limited to these specific examples.

[Organic semiconductor materials, organic thin films]
The organic semiconductor material of the present invention contains an organic compound represented by the formula (1) of the present invention. An organic thin film can be produced using an organic semiconductor material containing an organic compound represented by the formula (1) of the present invention. The thickness of the organic thin film varies depending on the application, but is usually 0.1 nm to 10 μm, preferably 0.5 nm to 3 μm, more preferably 1 nm to 1 μm.

  As a method for forming an organic thin film, generally, a vacuum process, a resistance heating vapor deposition method, an electron beam vapor deposition method, a sputtering method, a molecular lamination method, or the like; a solution process, a spin coating method, a drop cast method, Dip coating method, spray method, flexographic printing method, relief printing method such as resin relief printing, offset printing method, dry offset printing method, flat printing method such as pad printing method, intaglio printing method such as gravure printing method, silk screen printing Methods such as stencil printing, stencil printing, stencil printing, stencil printing, ink jet printing, microcontact printing, and the like; and combinations of these techniques. Among these, the resistance heating vapor deposition method which is a vacuum process is preferable.

[Organic electronics devices]
An organic electronic device can be produced using the organic compound represented by the formula (1) of the present invention as a material for electronics applications. Examples of the organic electronics device include a thin film transistor element, an organic photoelectric conversion element, an organic solar cell element, an organic EL element, an organic light emitting transistor element, and an organic semiconductor laser element. Next, these will be described in detail.

[Thin film transistor element]
First, the thin film transistor element will be described in detail.
A thin film transistor element has two electrodes (a source electrode and a drain electrode) in contact with a semiconductor thin film, and controls a current flowing between these electrodes by a voltage applied to another electrode called a gate electrode.

  In general, a structure in which a gate electrode is insulated by an insulating film (Metal-Insulator-Semiconductor MIS structure) is often used for a thin film transistor element. A MIS structure using a metal oxide film as an insulating film is called a MOS (Metal-Oxide-Semiconductor) structure. As a thin film transistor element having another structure, there is a structure in which a gate electrode is formed on a semiconductor thin film through a Schottky barrier (that is, an MES structure). In the case of a thin film transistor element using an organic semiconductor material, the MIS structure is used. Is often used.

  Hereinafter, the organic thin film transistor element including the semiconductor thin film containing the organic compound of the present invention will be described in more detail with reference to the drawings. The thin film transistor element of the present invention is an organic semiconductor material containing the organic compound of the present invention. As long as it is used, it is not limited to these structures.

FIG. 1 shows some examples of thin film transistor elements. In FIG. 1A to FIG. 1F and FIG. 2, members having the same function are denoted by the same reference numerals.
The thin film transistor elements 10A to 10F of each embodiment shown in FIGS. 1A to 1F include a source electrode 1, an organic semiconductor layer 2, a drain electrode 3, an insulator layer 4, a gate electrode 5, and a substrate 6. Yes. In addition, arrangement | positioning of each layer and an electrode can be suitably selected according to the use of a thin-film transistor element. The thin film transistor elements 10 </ b> A to 10 </ b> D and 10 </ b> F are called horizontal transistors because current flows in a direction parallel to the substrate 6. In the thin film transistor element 10A, a source electrode 1 and a drain electrode 3 are provided on a gate electrode 5 via an insulator layer 4, and an organic semiconductor layer 2 is further formed thereon, which is called a bottom contact-bottom gate structure. In the thin film transistor element 10B, an organic semiconductor layer 2 is provided on a gate electrode 5 with an insulator layer 4 interposed therebetween, and a source electrode 1 and a drain electrode 3 are further formed thereon, which is called a top contact-bottom gate structure. The thin film transistor element 10C has a source electrode 1 and a drain electrode 3 on an organic semiconductor layer 2, and further a gate electrode 5 formed thereon via an insulator layer 4, and has a top contact-top gate structure. is called. In the thin film transistor element 10D, a source electrode 1 is provided on a gate electrode 5 via an insulator layer 4, an organic semiconductor layer 2 is further formed thereon, and a drain electrode 3 is further formed thereon. & Bottom contact A structure called a bottom gate type transistor. In the thin film transistor element 10F, a source electrode 1 and a drain electrode 3 are provided on a substrate 6, an organic semiconductor layer 2 is further provided thereon, and a gate electrode 5 is formed thereon via an insulator layer 4. Bottom contact-top gate structure.

  The thin film transistor element 10E is a transistor having a vertical structure, that is, an electrostatic induction transistor (SIT). In this SIT, since a current flow spreads in a plane, a large amount of carriers 8 can move at a time. In addition, since the source electrode 1 and the drain electrode 3 are arranged vertically in the SIT, the distance between the electrodes can be reduced, so that the response is fast. Therefore, SIT can be preferably applied to applications such as flowing a large current and performing high-speed switching. Although FIG. 1E does not show the substrate, in the normal case, the substrate is provided outside the source electrode 1 or the drain electrode 3 in FIG. Hereinafter, this substrate is also referred to as “substrate 6”.

Next, each component in each embodiment shown in FIG. 1 will be described.
The substrate 6 needs to be able to hold each layer formed thereon without peeling off. As the substrate 6, for example, an insulating substrate such as a resin plate, a resin film, paper, a glass plate, a quartz plate, or a ceramic plate; an insulating layer is formed by coating or the like on a conductive substrate made of metal, an alloy, or the like. A multilayer substrate; a composite substrate composed of various combinations such as a combination of a resin and an inorganic material; and the like can be used. Examples of the resin film that can be used for the substrate 6 include films of polyethylene terephthalate, polyethylene naphthalate, polyethersulfone, polyamide, polyimide, polycarbonate, cellulose triacetate, polyetherimide, and the like. When a resin film or paper is used as the substrate 6, the thin film transistor elements 10A to 10F can be made flexible, and the thin film transistor elements 10A to 10F are flexible and light in weight, thereby improving practicality. The thickness of the substrate 6 is usually 1 μm to 10 mm, preferably 5 μm to 5 mm.

A conductive material is used for the source electrode 1, the drain electrode 3, and the gate electrode 5. Examples of the conductive material include platinum, gold, silver, aluminum, chromium, tungsten, tantalum, nickel, cobalt, copper, iron, lead, tin, titanium, indium, palladium, molybdenum, magnesium, calcium, and barium. Metals such as lithium, potassium, sodium and alloys containing them; conductive oxides such as InO ₂ , ZnO ₂ , SnO ₂ , ITO; polyaniline, polypyrrole, polythiophene, polyacetylene, polyparaphenylene, vinylene, polydiacetylene, etc. Conductive polymer compounds; semiconductors such as silicon, germanium, and gallium arsenide; carbon materials such as carbon black, fullerene, carbon nanotubes, graphite, and graphene; In addition, the conductive polymer compound or the semiconductor may be doped. Examples of the dopant used for doping include inorganic acids such as hydrochloric acid and sulfuric acid; organic acids having an acidic functional group such as sulfonic acid; Lewis acids such as PF ₅ , AsF ₅ and FeCl ₃ ; halogen atoms such as iodine; lithium, Metal atoms such as sodium and potassium; and the like. Boron, phosphorus, arsenic and the like are also frequently used as dopants for inorganic semiconductors such as silicon. A conductive composite material in which conductive molecules such as carbon black and metal particles are dispersed in the dopant is also used as the conductive material. In the source electrode 1 and the drain electrode 3 that are in direct contact with the organic semiconductor layer 2, selection of an appropriate work function, surface treatment, and the like are important in order to reduce contact resistance.

  Further, the structure of the thin film transistor elements 10A to 10F is a structure such as a distance (channel length) between the source electrode 1 and the drain electrode 3 and a width of the channel region (channel width) between the source electrode 1 and the drain electrode 3. It becomes an important factor that decides. The channel length is usually 0.01 to 300 μm, preferably 0.1 to 100 μm. If the channel length is short, the amount of current that can be extracted increases, but conversely, short channel effects such as the influence of contact resistance occur and control becomes difficult, so an appropriate channel length is required. The width (channel width) of the channel region between the source electrode 1 and the drain electrode 3 is usually 10 to 10000 μm, preferably 100 to 5000 μm. Further, the channel width can be further increased by making the structure of the source electrode 1 and the drain electrode 3 into a comb structure, etc., and can be set to an appropriate length depending on the required amount of current and the structure of the element. There is a need to.

The structures (shapes) of the source electrode 1 and the drain electrode 3 will be described. The structure of the source electrode 1 and the structure of the drain electrode 3 may be the same or different.
In the case of the bottom contact structure, in general, it is preferable to form the source electrode 1 and the drain electrode 3 using a lithography method, and to form the source electrode 1 and the drain electrode 3 in a rectangular parallelepiped shape. Recently, the printing accuracy by various printing methods has been improved, and it has become possible to accurately produce the source electrode 1 and the drain electrode 3 by using a method such as an ink jet printing method, a gravure printing method, or a screen printing method. ing. In the case of a top contact structure having the source electrode 1 and the drain electrode 3 on the organic semiconductor layer 2, the source electrode 1 and the drain electrode 3 can be produced by vapor deposition using a shadow mask or the like. It has also become possible to form the source electrode 1 and the drain electrode 3 by directly printing an electrode pattern using a technique such as inkjet. The lengths of the source electrode 1 and the drain electrode 3 may be the same as the channel width. The widths of the source electrode 1 and the drain electrode 3 are not particularly limited, but are preferably shorter in order to reduce the area of the thin film transistor elements 10A to 10F within a range in which the electrical characteristics can be stabilized. The width | variety of the source electrode 1 and the drain electrode 3 is 0.1-1000 micrometers normally, Preferably it is 0.5-100 micrometers. The thickness of the source electrode 1 and the drain electrode 3 is 0.1-1000 nm normally, Preferably it is 1-500 nm, More preferably, it is 5-200 nm. Although wiring is connected to the source electrode 1, the drain electrode 3, and the gate electrode 5, the wiring is also made of substantially the same material as the electrodes (the source electrode 1, the drain electrode 3, and the gate electrode 5).

As the insulator layer 4, an insulating material is used. Examples of the insulating material include polyparaxylylene, polyacrylate, polymethyl methacrylate, polyolefin, polystyrene, polyvinylphenol, polyamide, polyimide, polycarbonate, polyester, polyvinyl alcohol, polyvinyl acetate, polyurethane, polysulfone, Polymers such as fluororesins, epoxy resins, phenol resins, and copolymers thereof, metal oxides such as silicon dioxide, aluminum oxide, titanium oxide, and tantalum oxide; ferroelectric metal oxides such as SrTiO ₃ and BaTiO ₃ A dielectric such as nitride such as silicon nitride or aluminum nitride, sulfide or fluoride; or a polymer in which particles of these dielectrics are dispersed; or the like can be used. As the insulator layer 4, a layer having high electrical insulation characteristics can be preferably used in order to reduce the leakage current. Thereby, the layer thickness of the insulator layer 4 can be reduced, the insulation capacity of the insulator layer 4 can be increased, and the current that can be extracted from the thin film transistor elements 10A to 10D and 10F can be increased. In order to improve the mobility of the organic semiconductor layer 2, it is preferable that the surface of the insulator layer 4 is a smooth surface without unevenness in order to reduce the surface energy of the surface of the insulator layer 4. Therefore, as the insulator layer 4, a self-assembled monolayer or two insulator layers may be formed. The layer thickness of the insulator layer 4 varies depending on the material, but is usually 0.1 nm to 100 μm, preferably 0.5 nm to 50 μm, more preferably 1 nm to 10 μm.

  As the material of the organic semiconductor layer 2, an organic compound represented by the formula (1) of the present invention is used. Using the organic compound represented by the formula (1) of the present invention, the organic semiconductor layer 2 is formed as an organic thin film by the method for forming an organic thin film described above. For the purpose of improving the characteristics of the thin film transistor elements 10A to 10F and imparting other characteristics, other organic semiconductor materials and various additives are added to the organic compound represented by the formula (1) of the present invention as necessary. It is also possible to mix.

  In the thin film transistor elements 10A to 10F, at least one compound of the organic compounds represented by the formula (1) of the present invention is used as an organic semiconductor material constituting the organic semiconductor layer 2. When the organic semiconductor layer 2 containing the organic compound represented by the formula (1) is formed by a wet process, that is, when the organic semiconductor layer 2 is formed using a solvent, the organic semiconductor layer 2 is formed. It is preferable to use the organic semiconductor layer 2 after substantially evaporating the solvent. The organic semiconductor layer 2 is preferably formed by a vapor deposition method that is a dry process. For the purpose of improving the characteristics of the thin film transistor elements 10A to 10F, the organic semiconductor material constituting the organic semiconductor layer 2 may contain an additive such as a dopant.

  The additive is added in the range of usually 0.01 to 10% by mass, preferably 0.05 to 5% by mass, more preferably 0.1 to 3% by mass with respect to the total amount of the material of the organic semiconductor layer 2. Is done.

  Also, a plurality of layers may be formed for the organic semiconductor layer 2. The layer thickness of the organic semiconductor layer 2 is preferably as thin as possible without losing necessary functions. In the horizontal thin film transistor elements 10A to 10D and 10F, if the organic semiconductor layer 2 has a layer thickness equal to or larger than a predetermined thickness, the characteristics of the element do not depend on the layer thickness of the organic semiconductor layer 2, whereas the layer thickness of the organic semiconductor layer 2 is thick. This is because the leakage current often increases. The layer thickness of the organic semiconductor layer 2 for exhibiting a necessary function is usually 1 nm to 1 μm, preferably 5 nm to 500 nm, more preferably 10 nm to 300 nm.

  The thin film transistor elements 10A to 10F include, for example, between the substrate 6 and the insulator layer 4, between the insulator layer 4 and the organic semiconductor layer 2, or on the outer surface of the thin film transistor elements 10A to 10F as necessary. Can be provided. For example, when the protective layer is formed directly on the organic semiconductor layer 2 or via another layer, the influence of outside air such as humidity can be reduced. In addition, the formation of the protective layer has an advantage that the electrical characteristics can be stabilized, for example, the ON / OFF ratio of the thin film transistor elements 10A to 10F can be increased.

  The material for the protective layer is not particularly limited. For example, acrylic resins such as epoxy resin and polymethyl methacrylate, various resins such as polyurethane, polyimide, polyvinyl alcohol, fluororesin, and polyolefin; silicon oxide, aluminum oxide, silicon nitride Inorganic oxides such as nitrides, dielectrics such as nitride films, and the like are preferably used, and resins (polymers) having low oxygen and moisture permeability and low water absorption are particularly preferable. A gas barrier protective material developed for organic EL displays can also be used as the material of the protective layer. The layer thickness of the protective layer can be selected arbitrarily depending on the purpose, but is usually 100 nm to 1 mm.

  Moreover, it is possible to improve the characteristics of the thin film transistor elements 10A to 10F by performing surface modification or surface treatment in advance on the substrate 6 or the insulator layer 4 on which the organic semiconductor layer 2 is laminated. For example, by adjusting the degree of hydrophilicity / hydrophobicity of the surface of the substrate 6 by surface modification or surface treatment of the substrate 6, the film quality and film formability of the film formed thereon can be improved. In particular, the characteristics of organic semiconductor materials can vary greatly depending on the state of the film, such as molecular orientation. Therefore, the molecular orientation of the interface portion between the organic semiconductor layer 2 formed on the substrate 6 or the insulator layer 4 and the substrate 6 or the insulator layer 4 is controlled by the surface treatment on the substrate 6 or the insulator layer 4. In addition, it is considered that characteristics such as carrier mobility are improved by reducing the trap sites on the substrate 6 and the insulator layer 4.

  The trap site refers to a functional group such as a hydroxyl group present in the untreated substrate 6. When such a functional group is present in the substrate 6, electrons are attracted to the functional group, and as a result, carrier movement occurs. The degree decreases. Therefore, reducing trap sites on the substrate 6 and the insulator layer 4 is often effective for improving characteristics such as carrier mobility.

  Examples of the surface treatment for improving the properties as described above include self-assembled monolayer treatment with hexamethyldisilazane, octyltrichlorosilane, octadecyltrichlorosilane, octylphosphonic acid, octadecylphosphonic acid, decylthiol, etc .; polymer Surface treatment with etc .; acid treatment with hydrochloric acid, sulfuric acid, acetic acid, etc .; alkali treatment with sodium hydroxide, potassium hydroxide, calcium hydroxide, ammonia, etc .; ozone treatment; fluorination treatment; plasma treatment with oxygen, argon, etc .; Examples include a process for forming a blow jet film; a process for forming a thin film of other insulator or semiconductor; a mechanical process; an electrical process such as corona discharge; a rubbing process using fibers or the like;

  In these embodiments, for example, as a method of providing each layer such as the substrate 6, the insulator layer 4, and the organic semiconductor layer 2, for example, a vacuum deposition method, a sputtering method, a coating method, a printing method, a sol-gel method, or the like can be appropriately employed. .

  Next, a method for manufacturing a thin film transistor element according to the present invention will be described below with reference to FIG. 2, taking the top contact-bottom gate type thin film transistor element 10B of the embodiment shown in FIG. 1B as an example. This manufacturing method can be similarly applied to the thin film transistor elements 10A, 10C to 10F of the other embodiments described above.

(Processing of substrate 6 and substrate 6)
The thin film transistor element 10B is manufactured by providing various layers and electrodes necessary on the substrate 6 (see FIG. 2A). As the substrate 6, those described above can be used. It is also possible to perform the above-described surface treatment or the like on the substrate 6. The thickness of the substrate 6 is preferably thin as long as necessary functions are not hindered. Further, if necessary, the substrate 6 can have an electrode function.

(Formation of the gate electrode 5)
A gate electrode 5 is formed on the substrate 6 (see FIG. 2B). As the material of the gate electrode 5, those described above are used. As a method for forming the gate electrode 5, various methods can be used. For example, a vacuum deposition method, a sputtering method, a coating method, a thermal transfer method, a printing method, a sol-gel method, or the like is employed. It is preferable to perform patterning as necessary so as to obtain a desired shape during or after film formation. As a patterning method, various methods can be used. For example, a photolithography method combining photoresist patterning and etching can be used. In addition, evaporation methods using shadow masks; sputtering methods; ink-jet printing methods, screen printing methods, offset printing methods, letterpress printing and other printing methods; soft contact methods such as micro-contact printing methods; methods combining these methods It is also possible to perform patterning using the above. Although the thickness of the gate electrode 5 changes with materials, it is 0.1 nm-10 micrometers normally, Preferably it is 0.5 nm-5 micrometers, More preferably, it is 1 nm-3 micrometers. When the gate electrode 5 also serves as the substrate 6, the thickness of the gate electrode 5 may be larger than the above thickness range.

(Formation of insulator layer 4)
Next, the insulator layer 4 is formed on the gate electrode 5 (see FIG. 2C). As the material of the insulator layer 4, the materials described above are used. Various methods can be used for forming the insulator layer 4. Examples of the method for forming the insulator layer 4 include spin coating, spray coating, dip coating, casting, bar coating, blade coating, and other coating methods; screen printing, offset printing, inkjet printing, and the like. Printing methods such as vacuum deposition methods, molecular beam epitaxial growth methods, ion cluster beam methods, ion plating methods, sputtering methods, atmospheric pressure plasma methods, and CVD (chemical vapor deposition) methods. In addition, a method of forming a metal oxide film on a metal (including a semimetal such as silicon) by a sol-gel method or a thermal oxidation method (a method of forming an alumite film on aluminum, a silicon dioxide film on silicon) And the like. In the portion where the insulator layer 4 and the organic semiconductor layer 2 are in contact with each other, in order to satisfactorily orient the molecules constituting the semiconductor at the interface between the two layers, for example, the molecules of the organic compound represented by the above formula (1). The insulator layer 4 can be subjected to a predetermined surface treatment. As a surface treatment method, the same method as the surface treatment of the substrate 6 can be used. The layer thickness of the insulator layer 4 is preferably as thin as possible since the amount of electricity taken out from the thin film transistor element 10B can be increased by increasing the electric capacity by reducing the thickness. At this time, since the leakage current increases when the insulator layer 4 is a thin film, the insulator layer 4 is preferably thin as long as its function is not impaired.

(Formation of organic semiconductor layer 2)
Next, the organic semiconductor layer 2 is formed on the insulator layer 4 (see FIG. 2D). The organic semiconductor material containing the organic compound represented by the formula (1) of the present invention is used for forming the organic semiconductor layer 2. In forming the organic semiconductor layer 2, various methods can be used. As a method for forming the organic semiconductor layer 2, specifically, a forming method by a vacuum process such as a sputtering method, a CVD method, a molecular beam epitaxial growth method, a vacuum deposition method; a dip coating method, a die coater method, a roll coater method, Examples thereof include a coating method such as a bar coater method and a spin coat method, an ink jet printing method, a screen printing method, an offset printing method, and a forming method by a solution process such as a microcontact printing method.

First, a method for obtaining an organic semiconductor layer 2 by forming an organic semiconductor material by a vacuum process will be described. As a method for forming an organic semiconductor material by a vacuum process, the organic semiconductor material containing the organic compound represented by the formula (1) of the present invention is heated in a crucible or a metal boat under vacuum to evaporate organic material. There is a method in which a semiconductor material is attached (deposited) to a substrate (substrate 6, insulating layer 4, source electrode 1, drain electrode 3, etc.) on which the organic semiconductor layer 2 is formed, that is, a vacuum deposition method. Preferably employed. Under the present circumstances, a vacuum degree is 1.0 * 10 < ^-1 > Pa or less normally, Preferably it is 1.0 * 10 < ^-3 > Pa or less. In addition, since the characteristics of the organic semiconductor layer 2 and thus the characteristics of the thin film transistor element 10B may change depending on the substrate (base material) temperature (deposition temperature) during the deposition, it is preferable to carefully select the substrate temperature. The substrate temperature at the time of vapor deposition is usually 0 to 250 ° C, preferably 5 to 200 ° C, more preferably 10 to 180 ° C, still more preferably 15 to 150 ° C, and particularly preferably 20 to 130 ° C. ° C.

  The deposition rate is usually 0.001 nm / second to 10 nm / second, preferably 0.01 nm / second to 1 nm / second.

  Other methods may be used instead of the vapor deposition method in which the organic semiconductor material for forming the organic semiconductor layer 2 is heated and evaporated to adhere to the substrate (base material).

  Next, a method for obtaining an organic semiconductor layer 2 by forming an organic semiconductor material by a solution process will be described. A composition (ink) prepared by dissolving the organic compound represented by the formula (1) of the present invention in a solvent or the like and further adding an additive or the like if necessary is used as a substrate (base material) surface (insulation). It is applied to the exposed surface of the body layer 4, the source electrode 1, and the drain electrode 3). Coating methods include casting methods, spin coating methods, dip coating methods, blade coating methods, wire bar coating methods, spray coating methods, etc .; inkjet printing methods, screen printing methods, offset printing methods, flexographic printing methods, Examples thereof include a printing method such as a relief printing method; a soft lithography method such as a micro contact printing method; a method in which a plurality of these methods are combined.

  Furthermore, as a method similar to the coating method, the Langmuir-Blodgett method, in which a monomolecular film of an organic semiconductor layer produced by dropping the above ink on the water surface is transferred to a substrate (base material) and laminated, liquid crystal or melt state It is also possible to adopt a method in which the material is sandwiched between two substrates (base materials) and introduced between the substrates (base materials) by capillary action.

  The environment such as the temperature of the substrate (base material) and the composition at the time of film formation is also important, and the characteristics of the thin film transistor element 10B may change depending on the temperature of the substrate (base material) or the composition. Is preferably selected. The substrate temperature is usually from 0 to 200 ° C, preferably from 10 to 120 ° C, more preferably from 15 to 100 ° C. Since the selection of the substrate temperature largely depends on the solvent and the like in the composition to be used, care must be taken.

  The layer thickness of the organic semiconductor layer 2 produced by this method is preferably as thin as possible without impairing its function. When the layer thickness of the organic semiconductor layer 2 is increased, there is a concern that the leakage current increases. The layer thickness of the organic semiconductor layer 2 is usually 1 nm to 1 μm, preferably 5 nm to 500 nm, more preferably 10 nm to 300 nm.

  The organic semiconductor layer 2 (see FIG. 2D) thus formed can be further improved in characteristics by post-processing. For example, by heat treatment, distortion in the organic semiconductor layer 2 generated during film formation is reduced, pinholes in the organic semiconductor layer 2 are reduced, and arrangement / orientation in the organic semiconductor layer 2 can be controlled. For these reasons, the organic semiconductor characteristics of the organic semiconductor layer 2 can be improved and stabilized. In manufacturing the thin film transistor element 10B according to one embodiment of the present invention, this heat treatment is effective for improving the characteristics of the thin film transistor element 10B. The heat treatment is performed by heating the substrate (base material) after forming the organic semiconductor layer 2. The temperature of the heat treatment is not particularly limited, but is usually from room temperature to about 200 ° C, preferably 40 to 150 ° C, more preferably 45 to 120 ° C. The heat treatment time at this time is not particularly limited, but is usually about 10 seconds to 24 hours, preferably about 30 seconds to 3 hours. The atmosphere for the heat treatment may be air, but may be an inert atmosphere such as nitrogen or argon. As other post-processing, the shape of the organic semiconductor layer 2 can be controlled by solvent vapor.

  In addition, as another post-treatment method of the organic semiconductor layer 2, a characteristic change due to oxidation or reduction can be achieved by treating with an oxidizing or reducing gas such as oxygen or hydrogen, or an oxidizing or reducing liquid. Can also be induced. This can be used for the purpose of increasing or decreasing the carrier density in the film, for example.

In addition, in a technique called doping, the characteristics of the organic semiconductor layer 2 can be changed by adding a trace amount of element, atomic group, molecule, or polymer to the organic semiconductor layer 2. For example, acids such as oxygen, hydrogen, hydrochloric acid, sulfuric acid and sulfonic acid; Lewis acids such as PF ₅ , AsF ₅ and FeCl ₃ ; halogen atoms such as iodine; metal atoms such as sodium and potassium; acceptor compounds such as TCNQ and fullerene Can be doped into the organic semiconductor layer 2. Doping of the organic semiconductor layer 2 by these makes these gases contact the organic semiconductor layer 2, immerses the organic semiconductor layer 2 in these solutions, or makes the organic semiconductor layer 2 electrochemically doped by these. This can be achieved. The materials used for these dopings do not have to be added after the organic semiconductor layer 2 is produced. They can be added at the time of synthesizing the organic compound represented by the formula (1) of the present invention, or a composition (ink) can be used. In addition, when a solution process for producing the organic semiconductor layer 2 is used, it can be added to the composition (ink), or can be added in a process step for forming the organic semiconductor layer 2. Further, when the organic semiconductor layer 2 is formed by vapor deposition, a material used for doping is added to the material forming the organic semiconductor layer 2 at the time of vapor deposition, and co-evaporation is performed. Mixing in the atmosphere (producing the organic semiconductor layer 2 in an environment in which a material used for doping exists), or accelerating doping ions in vacuum and colliding with the organic semiconductor layer 2 for doping. Is possible.

  These doping effects include changes in electrical conductivity due to increase or decrease in carrier density, changes in carrier polarity (p-type and n-type), changes in Fermi level, and the like.

(Formation of source electrode 1 and drain electrode 3)
Next, the source electrode 1 and the drain electrode 3 are formed on the organic semiconductor layer 2 (see FIG. 2E). Processes such as the formation of the source electrode 1 and the drain electrode 3 can be performed according to the case of the gate electrode 5. Further, in the source electrode 1 and the drain electrode 3, various additives can be used in order to reduce the contact resistance with the organic semiconductor layer 2.

(Formation of protective layer 7)
Next, a protective layer 7 is formed on the organic semiconductor layer 2 as necessary (see FIG. 2F). Forming the protective layer 7 on the organic semiconductor layer 2 has an advantage that the influence of outside air can be minimized and the electrical characteristics of the organic thin film transistor element 10B can be stabilized. As the material for the protective layer 7, those described above are used. The layer thickness of the protective layer 7 may be any layer thickness depending on the purpose, but is usually 100 nm to 1 mm.

  As a film forming method for forming the protective layer 7, various methods can be adopted. When the protective layer is made of a resin, for example, a method of drying a resin solution after application to form a resin film; And a method of forming a resin film by polymerizing after applying or depositing a monomer. Cross-linking treatment may be performed after the resin film is formed. When the protective layer 7 is made of an inorganic material, for example, a formation method using a vacuum process such as a sputtering method or a vapor deposition method or a formation method using a solution process such as a sol-gel method can be used for forming the protective layer 7.

  In the thin film transistor element 10B, in addition to the organic semiconductor layer 2, a protective layer can be provided between the layers as necessary. The protective layers provided at these positions may help to stabilize the electrical characteristics of the thin film transistor element 10B.

  Since the thin film transistor element 10B uses the organic compound represented by the formula (1) as the organic semiconductor material, it can be manufactured by a relatively low temperature process. Accordingly, a substrate made of a flexible material such as a plastic plate or a plastic film that could not be used under conditions exposed to a high temperature can be used as the substrate 6. As a result, it is possible to manufacture a light-weight and flexible thin-film transistor element that is difficult to break, and the thin-film transistor element can be used as a switching element for an active matrix of a display.

(Formation of self-assembled monolayer on electrode)
When the organic semiconductor layer 2 is formed on the source electrode 1 and the drain electrode 3 as in the thin film transistor element 10A, the source electrode 1 and the drain electrode 3 can be surface-treated in advance. Such surface treatment is often effective for improving characteristics such as mobility and threshold voltage.

  Examples of the surface treatment for improving properties as described above include self-assembled monolayer treatment with thiol derivatives such as benzenethiol, pentafluorobenzenethiol, and alkanethiol.

  The thin film transistor element of the present invention can be used as an element constituting a digital or analog circuit such as a memory circuit, a signal driver circuit, or a signal processing circuit. Further, by combining these circuits, a display, an IC card, an IC tag, or the like can be manufactured. Furthermore, since the thin film transistor element of the present invention can change its characteristics by an external stimulus such as a chemical substance, it can be used as an FET (field effect transistor) sensor.

[Organic EL device]
Next, the organic EL element will be described.
Organic EL elements have attracted attention because they can be used in applications such as solid, self-luminous large-area color display and illumination, and many developments have been made. The organic EL device has a structure having a light emitting layer and a charge transport layer between a counter electrode composed of a cathode and an anode; an electron transport layer and a light emitting layer stacked between the counter electrodes. And a structure having three layers of hole transport layers; a structure having three or more layers between the counter electrodes; and the like, and a light emitting layer having a single layer Is also known.

Here, the hole transport layer has a function of injecting holes from the anode, transporting holes to the light emitting layer, facilitating injection of holes into the light emitting layer, and a function of blocking electrons. . The electron transport layer has a function of injecting electrons from the cathode, transporting electrons to the light emitting layer, facilitating injection of electrons into the light emitting layer, and a function of blocking holes. Furthermore, in the light emitting layer, excitons are generated by recombination of the injected electrons and holes, and energy emitted in the process of radiation deactivation of the excitons is detected as light emission.
Below, the preferable aspect of an organic EL element is described.

An organic EL element is an element that emits light by electric energy in which an organic thin film having one or more layers is formed between an anode and a cathode.
The anode that can be used in the organic EL element is an electrode having a function of injecting holes into the hole injection layer, the hole transport layer, and the light emitting layer. In general, a metal oxide, metal, alloy, conductive material, or the like having a work function of 4.5 eV or more is suitable as a material for the anode. The material of the anode is not particularly limited, but is a conductive metal oxide such as tin oxide (NESA), indium oxide, indium tin oxide (ITO), indium zinc oxide (IZO); gold Metals such as silver, platinum, chromium, aluminum, iron, cobalt, nickel, and tungsten; inorganic conductive materials such as copper iodide and copper sulfide; conductive polymers such as polythiophene, polypyrrole, and polyaniline; and carbon. Among these, it is preferable to use ITO or NESA as a material for the anode.

  If necessary, the anode may be composed of a plurality of materials, or may be composed of two or more layers. The resistance of the anode is not limited as long as it can supply a current sufficient for light emission of the organic EL element, but it is preferably low resistance from the viewpoint of power consumption of the organic EL element. For example, a conductive substrate (for example, an ITO substrate) having a sheet resistance value of 300Ω / □ or less functions as an anode of an organic EL element. However, a conductive substrate having a sheet resistance value of about several Ω / □ can be supplied. Therefore, it is desirable to use a conductive substrate having low resistance and high transmittance as the anode. The thickness of the anode such as the ITO substrate can be arbitrarily selected according to the resistance value, but is usually 5 to 1000 nm, preferably 10 to 500 nm. Examples of the method for forming an anode material such as ITO include a vapor deposition method, an electron beam method, a sputtering method, a chemical reaction method, and a coating method.

  The cathode that can be used in the organic EL element is an electrode having a function of injecting electrons into the electron injection layer, the electron transport layer, and the light emitting layer. As a material for the cathode, a metal or alloy having a small work function (approximately 4 eV or less) is generally suitable. Specific examples of metals that can be used for the cathode include, but are not limited to, platinum, gold, silver, copper, iron, tin, zinc, aluminum, indium, chromium, lithium, sodium, potassium, calcium, magnesium, and the like. Can be mentioned. Lithium, sodium, potassium, calcium, and magnesium are preferable for increasing the electron injection efficiency and improving the characteristics of the organic EL element. As a cathode using an alloy, an electrode made of an alloy of these low work function metals and a metal such as aluminum or silver, or an electrode having a structure in which these low work function metals and a metal such as aluminum or silver are laminated. Etc. can be used. An inorganic salt such as lithium fluoride can be used for the cathode having a laminated structure. Moreover, when taking out light emission not to the anode side but to the cathode side, a transparent electrode such as ITO that can be formed at as low a temperature as possible can be used for the cathode. Examples of the method for forming the cathode include a vapor deposition method, an electron beam method, a sputtering method, a chemical reaction method, and a coating method, but are not particularly limited. The resistance of the cathode is not limited as long as it can supply a sufficient current for light emission of the organic EL element, but it is preferably low resistance from the viewpoint of power consumption of the organic EL element, and several hundred to several Ω / □. The degree is preferred. The thickness of the cathode is usually 5 to 1000 nm, preferably 10 to 500 nm.

  Furthermore, for sealing and protection, the cathode can be protected with a protective material and sealed with a dehydrating agent. Examples of the protective material include oxides, nitrides, or mixtures thereof such as titanium oxide, silicon nitride, silicon oxide, silicon nitride oxide, and germanium oxide; polyvinyl alcohol, polyvinyl chloride, and hydrocarbon polymers. And polymers such as fluorine-based polymers. Examples of the dehydrating agent include barium oxide, phosphorus pentoxide, and calcium oxide.

Moreover, in order to take out light emission from an organic EL element, it is generally preferable to produce an electrode (anode, cathode) on a substrate that is sufficiently transparent in the emission wavelength region of the organic EL element. Examples of such a transparent substrate include a glass substrate and a polymer substrate. The glass substrate only needs to have a thickness sufficient to maintain mechanical and thermal strength, and preferably has a thickness of 0.5 mm or more. As the glass constituting the glass substrate, soda lime glass, non-alkali glass, quartz and the like are used. The glass should have fewer ions eluted from the glass, and is preferably alkali-free glass. As such glass, soda lime glass having a barrier coat such as SiO ₂ is commercially available, and this can also be used. Examples of the polymer constituting the polymer substrate include polycarbonate, polypropylene, polyethersulfone, polyetherimide, polyethylene terephthalate, polyethylene naphthalate, polyimide, polyamide, and acrylic resin.

The organic thin film of the organic EL element is formed as one layer or a plurality of layers between the anode and the cathode. By containing the organic compound represented by the formula (1) in the organic thin film, the organic EL element of the present invention that emits light by electric energy can be obtained.
The “layer” of one or more layers forming the organic thin film is a hole transport layer, an electron transport layer, a hole transport light-emitting layer, an electron transport light-emitting layer, a hole block layer, an electron block layer, a positive layer. It means a hole injection layer, an electron injection layer, a light emitting layer, or a single layer having the functions of these layers as shown in the following structural example 9). Examples of the configuration of the layer forming the organic thin film in the present invention include the following configuration examples 1) to 9), and any configuration may be used.

Configuration Example 1) Hole transport layer / electron transport light emitting layer.
2) Hole transport layer / light emitting layer / electron transport layer.
3) Hole transporting light emitting layer / electron transporting layer.
4) Hole transport layer / light emitting layer / hole blocking layer.
5) Hole transport layer / light emitting layer / hole blocking layer / electron transport layer.
6) Hole transporting light emitting layer / hole blocking layer / electron transporting layer.
7) In each of the combinations 1) to 6), a hole injection layer is further provided in front of the hole transport layer or the hole transport light emitting layer.
8) A structure in which an electron injecting layer is further provided in front of the electron transporting layer or the electron transporting light emitting layer in each of the combinations 1) to 7).
9) A configuration in which materials used in the combinations 1) to 8) are mixed, and only one layer containing the mixed materials is included.
In the above 9), a single layer formed of a material generally called a bipolar light-emitting material; or a single layer containing a light-emitting material and a hole transport material or an electron transport material may be provided. . In general, with a multi-layer structure, charges, that is, holes and / or electrons can be efficiently transported and these charges can be recombined. In general, the multilayer structure can suppress charge quenching and the like, thereby preventing deterioration of the stability of the organic EL element and improving light emission efficiency.

  The hole injection layer and the hole transport layer are formed by using one kind of hole transport material alone or by mixing or laminating two or more kinds of hole transport materials. Examples of the hole transport material include N, N′-diphenyl-N, N′-di (3-methylphenyl) -4,4′-diphenyl-1,1′-diamine, N, N′-dinaphthyl-N. , N′-diphenyl-4,4′-diphenyl-1,1′-diamine and the like, bis (N-allylcarbazole), bis (N-alkylcarbazole) s, pyrazoline derivatives, stilbene compounds, A heterocyclic compound typified by a hydrazone compound, a triazole derivative, an oxadiazole derivative, and a porphyrin derivative; a polymer system such as a polycarbonate, a styrene derivative, polyvinylcarbazole, or polysilane having the heterocyclic compound in the side chain can be preferably used. The hole transport material is not particularly limited as long as it is a substance that forms a thin film necessary for manufacturing an organic EL element, can inject holes from the anode, and can transport holes. As the hole injection layer provided between the hole transport layer and the anode for improving the hole injection property, a phthalocyanine derivative; m-MTDATA (4,4 ′, 4 ″ -tris [phenyl (m- Those produced using starburst amines such as (tolyl) amino] triphenylamine); polythiophenes such as PEDOT (poly (3,4-ethylenedioxythiophene)), polymers such as polyvinylcarbazole derivatives, etc. Can be mentioned.

  The electron injection layer and the electron transport layer are formed of an electron transport material alone or by laminating two or more kinds of electron transport materials. As the electron transport material, it is necessary to efficiently transport electrons injected from the cathode between electrodes (anode and cathode) to which an electric field is applied. The electron transport material has high electron injection efficiency, and it is preferable to transport the injected electrons efficiently. For this purpose, the electron transport material is required to be a substance having a high electron affinity, a high electron mobility, excellent stability, and a trapping impurity that is not easily generated during manufacture and use. As an electron transport material satisfying such conditions, quinolinol derivative metal complexes represented by tris (8-quinolinolato) aluminum complexes, trobolone metal complexes, perylene derivatives, perinone derivatives, naphthalimide derivatives, naphthalic acid derivatives, oxazole derivatives, oxalates Examples include diazole derivatives, thiazole derivatives, thiadiazole derivatives, triazole derivatives, bisstyryl derivatives, pyrazine derivatives, phenanthroline derivatives, benzoxazole derivatives, and quinoxaline derivatives, but are not particularly limited. These electron transport materials can be used singly, but a plurality of different electron transport materials can be laminated or mixed and used. Examples of the electron injection layer provided between the electron transport layer and the cathode for improving the electron injection property include metals such as cesium, lithium, and strontium, lithium fluoride, and the like.

  The hole blocking layer is formed of one kind of hole blocking substance alone or by laminating or mixing two or more kinds of hole blocking substances. As the hole blocking substance, phenanthroline derivatives such as bathophenanthroline and bathocuproin, silole derivatives, quinolinol derivative metal complexes, oxadiazole derivatives, oxazole derivatives and the like are preferable. However, the hole blocking substance is not particularly limited as long as it is a compound that can prevent holes from flowing out from the cathode side to the outside of the device and thereby reducing the light emission efficiency.

  The light emitting layer means an organic thin film that emits light. For example, a hole transporting layer (hole transporting light emitting layer), an electron transporting layer (electron transporting light emitting layer), or bipolar transport having strong light emitting properties. Is a layer. The light emitting layer may be formed of a light emitting material (host material, dopant material, etc.), and may be a mixture of the host material and the dopant material or the host material alone. Each of the host material and the dopant material may be one kind of material or a combination of plural kinds of materials.

  The dopant material may be included in the entire host material, or may be included partially. The dopant material may be either laminated or dispersed. Examples of the light emitting layer include the above-described hole transport layer and electron transport layer. Materials used for the light-emitting layer include carbazole derivatives, anthracene derivatives, naphthalene derivatives, phenanthrene derivatives, phenylbutadiene derivatives, styryl derivatives, pyrene derivatives, perylene derivatives, quinoline derivatives, tetracene derivatives, perylene derivatives, quinacridone derivatives, coumarin derivatives, Examples thereof include porphyrin derivatives and phosphorescent metal complexes (Ir complex, Pt complex, Eu complex, etc.).

  As a method for forming each layer of the organic thin film in the organic EL device, generally, a vacuum process, a resistance heating vapor deposition method, an electron beam vapor deposition method, a sputtering method, a molecular lamination method; a solution process, a casting method, and a spin coating are used. Coating methods such as dip coating, dip coating, blade coating, wire bar coating, and spray coating; solution processes such as inkjet printing, screen printing, offset printing, letterpress printing, etc .; solution processes Soft lithography techniques such as the microcontact printing method; a combination of these techniques, and the like. The thickness of each layer of the organic thin film is not limited because it depends on the resistance value and charge mobility of the constituent materials, but is selected from 0.1 to 500 nm. The thickness of each layer of the organic thin film is preferably 0.5 to 300 nm, more preferably 1 to 100 nm.

  Of the organic thin films of the organic EL device in the present invention, one or a plurality of organic thin films such as a light emitting layer, a hole transport layer, and an electron transport layer existing between the anode and the cathode are represented by the formula (1). By including the organic compound represented, an organic EL element that emits light efficiently even with low electrical energy can be obtained.

  The layer containing the organic compound represented by the formula (1) can be formed in one layer or a plurality of layers between the anode and the cathode. Although there is no restriction | limiting in particular in the site | part which uses the organic compound represented by Formula (1), It can use suitably as a host material combined with a dopant material as a constituent material of a positive hole transport layer or a light emitting layer.

  The organic compound represented by the formula (1) can be suitably used as a material for the hole transport layer or the light emitting layer. The organic compound represented by the formula (1) may be used in combination with other materials such as the electron transport material, hole transport material, or light emitting material described above, or may be used in combination with other materials. can do.

When the organic compound represented by the formula (1) is used as a host material in combination with a dopant material, the dopant material is not particularly limited, and specifically, for example, bis (diisopropylphenyl) perylenetetracarboxylic Berylene derivatives such as acid imides, perinone derivatives, 4- (dicyanomethylene) -2-methyl-6- (p-dimethylaminostyryl) -4H-pyran (DCM) and its analogs, magnesium phthalocyanine, aluminum chlorophthalocyanine, etc. metal phthalocyanine derivatives, rhodamine compounds, Deazafurabin derivatives, coumarin derivatives, oxazine compounds, squarylium compounds, violanthrone compound, Nile red, 5- Shianopirometen -BF can ₄ be used as pyrromethene derivative complexes . In addition, as a phosphorescent material, Eu complexes having acetylacetone, benzoylacetone, phenanthroline, or the like as ligands, porphyrins such as Ir complexes, Ru complexes, Pt complexes, Os complexes, or ortho metal metal complexes may be used as dopant materials. it can. In addition, when two types of dopant materials are used in combination, the energy from the host material (host dye) is efficiently transferred using an assist dopant such as rubrene to obtain light emission with improved color purity. Is also possible. In any case, in order to obtain high luminance characteristics, it is preferable to dope those having a high fluorescence quantum yield.

  The dopant material is used in an amount of 30% by mass or less based on the host material because a concentration quenching phenomenon occurs when the amount used is too large. The amount of the dopant material used is preferably 20% by mass or less, more preferably 10% by mass or less based on the host material. As a method of doping the host material with the dopant material in the light emitting layer, a method of forming the light emitting layer by a co-evaporation method of the dopant material and the host material can be used, but after the dopant material is mixed with the host material in advance. You may use the method of vapor-depositing simultaneously. It is also possible to use a dopant material sandwiched between host materials. In this case, the dopant material may be laminated with the host material as one or more dopant layers.

  Each layer of these dopant layers may be formed of a single dopant material, or the dopant material may be mixed with a host material or the like. It is also possible to use the dopant material by dissolving or dispersing it in a polymer binder. Examples of the polymer binder include polyvinyl chloride, polycarbonate, polystyrene, polystyrene sulfonic acid, poly (N-vinylcarbazole), poly (methyl) (meth) acrylate, polybutyl methacrylate, polyester, polysulfone, Solvent-soluble resins such as polyphenylene oxide, polybutadiene, hydrocarbon resin, ketone resin, phenoxy resin, polysulfone, polyamide, ethyl cellulose, vinyl acetate, ABS resin (acrylonitrile-butadiene-styrene resin), polyurethane resin; phenol resin, xylene resin, petroleum Examples thereof include curable resins such as resins, urea resins, melamine resins, unsaturated polyester resins, alkyd resins, epoxy resins, and silicone resins.

  The organic EL element can be suitably used as a flat panel display. The organic EL element can also be used as a flat backlight. In this case, either an organic EL element that emits colored light or an organic EL element that emits white light can be used as a flat backlight. The backlight is mainly used for the purpose of improving the visibility of a display device that does not emit light, and is used for a liquid crystal display device, a clock, an audio device, an automobile panel, a display board, a sign, and the like. In particular, in the backlight of a liquid crystal display device, particularly a liquid crystal display device for personal computer applications where thinning is an issue, it has been difficult to reduce the thickness of the conventional backlight because it consists of a fluorescent lamp and a light guide plate. However, since the backlight using the organic EL element of the present invention is thin and lightweight, the above problems can be solved. Similarly, the organic EL device of the present invention can be usefully used for illumination.

  When the organic compound represented by the formula (1) of the present invention is used, an organic EL display device (a display device using an organic EL element) having high emission efficiency and a long lifetime can be obtained. Furthermore, by combining the organic EL display device with the thin film transistor element of the present invention, it becomes possible to supply an organic EL display device in which the applied voltage on / off phenomenon is electrically controlled with high accuracy at low cost.

[Organic light-emitting transistor element]
Next, the organic light emitting transistor element will be described. The organic compound represented by the formula (1) can also be used for an organic light-emitting transistor element. An organic light-emitting transistor element that combines a thin-film transistor element and an organic electroluminescence element has a structure in which a drive circuit and a light-emitting part in a display are integrated, and the area occupied by the drive transistor circuit can be reduced. Rate. That is, the number of parts can be reduced and the manufacturing process is simplified, so that a display with lower cost can be obtained. In principle, electrons and holes are simultaneously injected into the organic light emitting material from the source electrode and the drain electrode of the thin film transistor element, and light is emitted by recombination. The adjustment of the light emission amount is controlled by the electric field from the gate electrode.

  The structure of the organic light emitting transistor element may be the same as that described in the section of the thin film transistor element. In that case, a material for the light emitting transistor element can be used instead of the material for the thin film transistor element. The organic light-emitting transistor element can desirably select materials and processes to be used as appropriate according to the characteristics of the organic semiconductor material used for the organic semiconductor layer, and preferably has a configuration for extracting light to the outside. In a normal thin film transistor element, it is only necessary to inject one of electrons or holes. However, in the case of an organic light emitting transistor element, light is emitted by the combination of electrons and holes in the organic semiconductor layer. A structure that promotes effective charge injection, coupling, and light emission is preferable.

[Organic photoelectric conversion element]
The organic compound represented by the formula (1) of the present invention can be used as a constituent material of an organic photoelectric conversion element by utilizing its semiconductor characteristics. Examples of the organic photoelectric conversion element include a charge coupled device (CCD) having a function of converting a video signal such as a moving image or a still image into a digital signal as an image sensor that is a solid-state imaging element. The organic photoelectric conversion element using the organic compound represented by the formula (1) of the present invention is expected to have advantages such as lower cost, larger area processability, and flexible functionality unique to organic matter.

[Organic solar cell element]
A flexible and low-cost organic solar cell element can be easily produced using the organic compound represented by the formula (1) of the present invention. In other words, since the organic solar cell element is a solid element, it is advantageous in terms of flexibility and life improvement. Conventionally, an organic solar cell element using an organic thin film semiconductor combined with a conductive polymer, fullerene, etc. Development was mainstream, but power conversion efficiency is a problem.

  In general, the configuration of an organic solar cell element is similar to that of a silicon-based solar cell, in which a layer for generating power (a power generation layer) is sandwiched between an anode and a cathode, and holes and electrons generated by absorbing light are absorbed by each electrode. By receiving it functions as a solar cell. The power generation layer is composed of a p-type donor material, an n-type acceptor material, and other materials such as a buffer layer. A solar cell in which an organic material is used as a material for the power generation layer is used as an organic solar cell. It is called a battery element.

  Examples of the structure of the organic solar cell element include a Schottky junction, a heterojunction, a bulk heterojunction, a nanostructure junction, and a hybrid. The organic solar cell element functions as a solar cell by each material efficiently absorbing incident light, generating charges, and separating, transporting, and collecting the generated charges (holes and electrons). In addition, the structure of an example of the heterojunction element which is a structure of a general organic solar cell element was shown in FIG.

  The organic solar cell element 20 shown in FIG. 3 is formed on the substrate 21, the anode 22 formed on the upper surface of the substrate 21, the power generation layer 23 formed on the upper surface of the anode 22, and the upper surface of the power generation layer 23. The power generation layer 23 is formed of a p-type layer 231 made of a p-type donor material on the upper surface of the anode 22 and an n-type formed on the upper surface of the p-type layer 231. An n-type layer 232 made of the acceptor material and a buffer layer 233 formed on the upper surface of the n-type layer 232.

Next, components of the organic solar cell element will be described.
The anode and cathode in the organic solar cell element are the same as those of the organic EL element described above. Since the anode and the cathode need to take in light efficiently, it is desirable to use electrodes having transparency in the absorption wavelength region of the power generation layer. In order to have good solar cell characteristics, it is preferable that the anode and the cathode have a sheet resistance of 20Ω / □ or less and a light transmittance of 85% or more.

  The power generation layer in the organic solar cell element is formed of one layer or a plurality of layers of an organic thin film containing at least the organic compound represented by the formula (1) of the present invention. The organic solar cell element can take the structure shown above, but basically includes a p-type donor material, an n-type acceptor material, and a buffer layer.

  As the p-type donor material, a compound capable of transporting holes in the same manner as the material for the hole injection layer and the hole transport layer described in the section of the organic EL element; a polyparaphenylene vinylene derivative, a polythiophene derivative, Π-conjugated polymers such as polyfluorene derivatives and polyaniline derivatives; carbazole and other polymers having a heterocyclic ring in the side chain. Examples of the p-type donor material include low molecular compounds such as pentacene derivatives, rubrene derivatives, porphyrin derivatives, phthalocyanine derivatives, indigo derivatives, quinacridone derivatives, merocyanine derivatives, cyanine derivatives, squalium derivatives, and benzoquinone derivatives.

The n-type acceptor material is basically a compound capable of transporting electrons as in the electron transport layer described in the section of the organic EL device; an oligomer or polymer having pyridine and its derivative as a skeleton, quinoline and its derivative as a skeleton Oligomers and polymers, polymers having benzophenanthrolines and derivatives thereof; polymer materials such as cyanopolyphenylene vinylene (CN-PPV) and derivatives thereof; fluorinated phthalocyanine derivatives, perylene derivatives, naphthalene derivatives, bathocuproine derivatives, fullerenes (C60 or the like C70) and their derivatives (e.g., PCBM (phenyl _{C 61} butyric acid methyl ester),), and low-molecular material such as is.
As the p-type donor material and the n-type acceptor material, materials that efficiently absorb light and generate charges are preferable, and materials having a high extinction coefficient are preferable.

  The organic compound of the formula (1) of the present invention can be suitably used particularly as a p-type donor material. The method for forming the organic thin film for the power generation layer of the organic solar cell may be the same as the method described in the above-mentioned section of the organic EL element. Although the thickness of the organic thin film varies depending on the configuration of the solar cell, it is better to thicken it in order to absorb light sufficiently and prevent short-circuiting, but it is thin because it is better to transport the generated charge. Is more suitable. In general, the thickness of the organic thin film as the power generation layer is preferably about 10 to 500 nm.

[Organic semiconductor laser element]
Since the organic compound represented by the formula (1) of the present invention is an organic compound having semiconductor characteristics, utilization as an organic semiconductor laser element is expected.
That is, if a resonator structure is incorporated in an organic semiconductor element containing the organic compound represented by the formula (1) of the present invention and carriers are efficiently injected to sufficiently increase the density of excited states, It is expected to be amplified and lead to laser oscillation. Conventionally, only laser oscillation by optical excitation has been observed, and it is very difficult to inject high-density carriers necessary for laser oscillation by electrical excitation into an organic semiconductor element to generate a high-density excitation state. Although proposed, the use of an organic semiconductor element containing an organic compound represented by the formula (1) of the present invention is expected to cause highly efficient light emission (electroluminescence).

  EXAMPLES Hereinafter, although an Example demonstrates this invention further in detail, this invention is not limited to these examples. In the examples, M represents the molar concentration, and the compound formula numbers correspond to the formula numbers of the compounds specifically described above. Moreover, the reaction temperature described the internal temperature in a reaction system unless there is particular notice.

Various compounds obtained in the synthesis examples were measured for EI-MS spectrum (electron impact mass spectrometry spectrum), ¹ H-NMR spectrum (proton nuclear magnetic resonance spectrum), and λmax (maximum absorption wavelength) as necessary. To determine its structure. The measuring instruments used for these measurements are as follows.

EI-MS spectrum: gas chromatograph mass spectrometer (model name “QP-5050A”, manufactured by Shimadzu Corporation)
¹ H-NMR spectrum: nuclear magnetic resonance apparatus (model name “JEOL Lambda 400”, manufactured by JEOL Ltd.)
Maximum absorption wavelength: UV-visible near-infrared spectrophotometer (model name “UV-3150”, manufactured by Shimadzu Corporation)

[Example 1] (Synthesis of an organic compound of an example of the present invention represented by the formula (11) in the above specific example)
(Step 1) Synthesis of Intermediate Compound Represented by Formula (3-1) below In this step, a compound represented by the following formula (2-1) (R ^{6 of} formula (2) is represented according to the following reaction formula. , R ⁷ , R ¹⁴ , and R ¹⁵ are all hydrogen atoms) to an intermediate compound represented by the following formula (3-1) (R ⁶ , R ⁷ , R ¹⁴ , and A compound in which all of R ¹⁵ are hydrogen atoms) was synthesized.

Specifically, in a nitrogen atmosphere at −78 ° C., 675 mg (2.8 mmol) of naphtho [2,3-b: 6,7-b ′] dithiophene (a compound represented by the formula (2-1)) was added. A solution obtained by dissolving in 80 ml of anhydrous tetrahydrofuran (THF) was slowly mixed with 5.7 ml (8.9 mmol) of a 1.57N hexane solution of n-butyllithium (n-BuLi), and then heated for 1.5 hours. Refluxed. The reaction solution was cooled to −78 ° C., 2.24 g (11.2 mmol) of trimethyltin chloride was added thereto, and the mixture was stirred at room temperature for 11 hours, and then 100 ml of water was added. The obtained mixture was separated, the aqueous layer was extracted 3 times with 100 ml of methylene chloride, the organic layer was dried over anhydrous magnesium sulfate (MgSO ₄ ), and further concentrated under reduced pressure. The residue obtained by concentration under reduced pressure was recrystallized from acetone to obtain 861 mg (yield 54%) of a compound represented by the formula (3-1) as a yellow solid.

The measurement results of the ¹ H-NMR spectrum and EI-MS spectrum of the compound represented by the formula (3-1) were as follows.
¹ H-NMR (400 MHz, CDCl 3) 0.48 (s, 18H), 7.49 (s, 2H), 8.35 (s, 2H), 8.48 (s, 2H); EI-MS (70 eV ) M / z = 566 (M ⁺ )

(Step 2) Synthesis of Intermediate Compound Represented by Formula (b) below In this step, an intermediate compound represented by the following formula (b) (R ¹ to R of Formula (4) is represented according to the following reaction formula. ^A compound in which all of ⁵ and R ¹⁶ are hydrogen atoms; a compound in which all of R ^{8 to} R ¹³ in formula (5) are hydrogen atoms) was synthesized.

  Specifically, it was obtained by dissolving 2.0 g (6.2 mmol) of 3-methylthio-2-naphthyltrifluoromethanesulfonate (compound represented by the above formula (7)) in 100 ml of methylene chloride under a nitrogen atmosphere. The solution was cooled to 0 ° C., 1.07 g (6.2 mmol) of metachloroperbenzoic acid (mCPBA) was added, and the mixture was stirred for 22 hours while gradually returning to room temperature. After adding 30 ml of 2M aqueous potassium carbonate solution to the resulting reaction solution, the mixture was separated, the aqueous layer was extracted twice with 50 ml of methylene chloride, and the organic layer was washed with 30 ml of 2M aqueous potassium carbonate solution. Thereafter, the organic layer was dried over anhydrous magnesium sulfate and further concentrated under reduced pressure. The residue obtained by concentration under reduced pressure is purified by column chromatography (filler: silica gel, developing solvent: ethyl acetate), whereby 1.82 g (yield 87%) of the compound represented by the above formula (b) is white. Obtained as a solid.

The measurement results of ¹ H-NMR spectrum and EI-MS spectrum of the compound represented by the formula (b) were as follows.
¹ H-NMR (400 MHz, CDCl ₃ ) 2.90 (s, 3H), 7.69 (m, 2H), 7.86 (s, 1H), 7.95 (quart, 1H), 8.03 ( quart, 1H), 8.51 (s, 1H); EI-MS (70 eV) m / z = 338 (M ⁺ )

(Step 3) Synthesis of Intermediate Compound Represented by Formula (c) below In this step, the compound represented by Formula (3-1) obtained in Step 1 and Step 2 were obtained according to the following reaction formula. From the obtained compound represented by the formula (b), an intermediate compound represented by the following formula (c) (a compound in which all of R ^{1 to} R ^{16 in} the formula (6) are hydrogen atoms) was synthesized.

Specifically, 0.70 g (1.24 mmol) of the compound represented by Formula (3-1) obtained in Step 1 and the compound represented by Formula (b) obtained in Step 2 under a nitrogen atmosphere. To a solution obtained by dissolving 1.00 g (2.96 mmol) in 55 mL of toluene was added 143 mg (0.124 mmol) of tetrakis (triphenylphosphine) palladium (0) (Pd (PPh ₃ ) ₄ ) and the reflux temperature. For 63 hours. Thereafter, the reaction solution was cooled to room temperature, and the solid content was collected by filtration. The solid content collected by filtration was washed with water and ethanol to obtain 0.46 g (yield 60%) of the compound represented by the formula (c) as an ocherous solid.

The measurement results of the ¹ H-NMR spectrum and EI-MS spectrum of the compound represented by the formula (c) were as follows.
¹ H-NMR (400 MHz, CDCl ₃ ) 2.61 (s, 6H), 7.66 (m, 6H), 7.97 (quart, 2H), 8.07 (quart, 2H), 8.13 ( s, 2H), 8.46 (s, 2H), 8.53 (s, 2H), 8.67 (s, 2H); EI-MS (70 eV) m / z = 616 (M ⁺ )

(Step 4) Synthesis of the organic compound of the present invention represented by the following formula (11) In this step, from the compound represented by the formula (c) obtained in the step 3, the formula (c) The compound represented by 11) was synthesized.

  Specifically, 0.25 g (0.41 mmol) of the compound represented by the formula (c) obtained in Step 3 was added to 20 ml of trifluoromethanesulfonic acid (TfOH) under a nitrogen atmosphere and stirred at room temperature for 96 hours. did. After completion of the reaction, the reaction mixture was poured into ice water, and the resulting precipitate was filtered off and washed with water to obtain a solid. Under a nitrogen atmosphere, the solid content obtained above was added to 25 ml of pyridine, heated and refluxed for 45 hours, water was added, and the deposited precipitate was filtered and washed with water, methanol, and acetone. The washed precipitate obtained above is dried and then subjected to vacuum sublimation purification, whereby 22 mg (yield 8%) of the organic compound according to an example of the present invention represented by formula (11) is converted into a red solid. Got as.

The measurement results of the EI-MS spectrum and the maximum absorption wavelength of the organic compound represented by the formula (11) were as follows.
EI-MS (70 eV) m / z = 552 (M ⁺ ); λmax: 536 nm (thin film)
Moreover, the ultraviolet-visible absorption spectrum of the thin film which consists of an organic compound represented by this Formula (11) is shown in FIG.

[Example 2] (Thin film transistor element according to an example of the present invention using the organic compound represented by the formula (11) obtained in Example 1 (bottom contact-bottom gate type thin film transistor element, see FIG. 1A) ) Production and evaluation)
An n-doped silicon wafer (surface resistance of 0.02 Ω · cm or less, in FIG. 1A) with a SiO ₂ thermal oxide film (insulator layer 4 in FIG. 1A) having a thickness of 300 nm subjected to hexamethyldisilazane treatment. A shadow mask for electrode preparation is attached on the back surface of the surface with the SiO2 thermal oxide film in the gate electrode 5 and the substrate 6), and is placed in a vacuum vapor deposition apparatus. The degree of vacuum in the apparatus is 1.0 × 10 ^-4 Pa or less, and the gold electrode, that is, the source electrode (source electrode 1 in FIG. 1A) and the drain electrode (drain electrode 3 in FIG. 1A) are formed by resistance heating vapor deposition. Vapor deposited to a thickness of 50 nm.

  Next, this substrate with a gold electrode was treated with an isopropyl alcohol solution of pentafluorobenzenethiol to form a self-assembled monolayer on the gold electrode. Further, after washing the substrate with isopropyl alcohol, the substrate was heated to 70 ° C. on a hot plate and dried.

Next, a shadow mask for an organic semiconductor is mounted on the substrate, placed in a vacuum deposition apparatus, and evacuated until the degree of vacuum in the apparatus is 1.0 × 10 ⁻³ Pa or less, thereby forming a gold electrode on the substrate. The organic compound represented by the formula (11) obtained in Example 1 was added on the surface on the side subjected to the resistance heating vapor deposition method under the condition of the substrate temperature (deposition temperature) of about 100 ° C. After depositing to a thickness of 50 nm at a deposition rate of sec to form an organic semiconductor layer (organic semiconductor layer 2 in FIG. 1A), the shadow mask for electrode preparation was removed. Thus, a field effect thin film transistor element (channel length 50 μm, channel width 2000 μm) according to an example of the present invention was obtained.

  The obtained organic transistor element was installed in a prober, and semiconductor characteristics were measured using a semiconductor parameter analyzer (model name “4200SCS”, manufactured by TFF Keithley Instruments Co., Ltd.).

FIG. 5 is a graph showing the semiconductor characteristics of the thin film transistor device according to an example of the present invention obtained in this example. The drain voltage is fixed to −60 V which is a saturation region, and the gate voltage is scanned from 40 V to −60 V. The results of measuring drain current-gate voltage characteristics (transfer characteristics) are shown. Specifically, in FIG. 5, the horizontal axis represents the gate voltage (V _g / V), the vertical axis represents the drain current (−I _d / A; left end scale), and the square root of the absolute value of the drain current (| I _d | ^1/2 / A ^1/2 ; right end scale), and is a graph showing the semiconductor characteristics of the thin film transistor element produced in Example 2. In FIG. 5, the broken line indicates the semiconductor characteristics immediately after fabrication, and the solid line indicates the semiconductor characteristics after being left in the atmosphere for one week.

  From the measurement results shown in FIG. 5, the threshold voltage, carrier mobility, and on / off ratio of the thin film transistor element fabricated in Example 2 were determined by the methods described below.

<Threshold voltage>
In the curve showing the relationship between the gate voltage (V _g / V) and the square root of the absolute value of the drain current (| I _d | ^1/2 / A ^1/2 ) shown in FIG. It has changed greatly. In the curve showing the relationship between the gate voltage (V _g / V) and the square root of the absolute value of the drain current (−I _d / A) shown in FIG. (−60 to −30V in the measurement result illustrated in FIG. 5), and a voltage value at a point where the straight line obtained by extrapolating the approximate line intersects the X axis (a point where I _d = 0A) is obtained as a threshold voltage. It was.

<Carrier mobility>
Since the drain current-gate voltage characteristic in the saturation region is expressed by the following formula (a), the carrier mobility was calculated using the formula (a).

I _d = (1/2) W · μ · Cp (V _g −Vth) ² / L (a)
Where I _d : drain current
W: Channel width
μ: Carrier mobility
Cp: Capacitance of the insulator layer 4 (SiO ₂ thermal oxide film)
V _g : gate voltage Vth: threshold voltage
L: Channel length

In this measurement, the channel width W is 2000 μm, the capacitance of the insulator layer 4 is 11.5 × 10 ⁻⁹ F, and the channel length L is 50 μm. The gate voltage Vg was set to −60 V that becomes a saturation region.

<On / off ratio>
Within the measurement range of the drain current-gate voltage characteristics, the on / off ratio was calculated as the ratio of the maximum value of drain current (current value when V _d = -60 V) and the minimum value of drain current.

Based on the above measurements and calculations, the threshold voltage (Vth) immediately after fabrication of the thin film transistor element obtained in Example 2 is −8 V, the carrier mobility is 2.4 × 10 ⁻² cm ² / Vs, and the on / off ratio ( _Ion / _Ioff ) was 7.8 × 10 ⁴ .

The threshold voltage (Vth) after leaving the thin film transistor element in the atmosphere for one week is −5 V, the carrier mobility is 2.0 × 10 ⁻² cm ² / Vs, and the on / off ratio (I _on / I _off). ) Was 6.0 × 10 ⁴ . From this result, it is clear that this thin film transistor element has high atmospheric stability.

  [Comparative Example 1] (Production and evaluation of comparative thin film transistor element (bottom contact-bottom gate type thin film transistor element) using bisbenzothienonaphthodithiophene described in Patent Document 6)

  For comparison in the same manner as in Example 2, except that bisbenzothienonaphthodithiophene represented by the following formula (x) was used instead of the compound represented by the formula (11) obtained in Example 1. The thin film transistor element was manufactured, and the semiconductor characteristics were measured by the same method as in Example 2.

  FIG. 6 is a graph showing the semiconductor characteristics (transfer characteristics) of the comparative thin film transistor element obtained in Comparative Example 1. In FIG. 6, the broken line indicates the semiconductor characteristics immediately after fabrication, and the solid line indicates the semiconductor characteristics after being left in the atmosphere for one week.

From the measurement results shown in FIG. 6, the threshold voltage (Vth) immediately after fabrication of the thin film transistor element fabricated in Comparative Example 1 is −6 V, the carrier mobility is 3.9 × 10 ⁻² cm ² / Vs, and the on / off ratio. (I _on / I _off ) was 3.1 × 10 ⁵ . Further, the threshold voltage (Vth) after leaving the thin film transistor element in the atmosphere for one week is 18 V, the carrier mobility is 2.6 × 10 ⁻² cm ² / Vs, and the on / off ratio (I _on / I _off ). Was 5.6 × 10 ² .

  As is clear from the above examples, the organic compound represented by the formula (1) of the present invention exhibits excellent semiconductor characteristics as an organic semiconductor material constituting the organic thin film transistor element, and is a material for organic electronic devices. It can be said that it is a very useful organic compound having high versatility.

DESCRIPTION OF SYMBOLS 1 Source electrode 2 Organic semiconductor layer 3 Drain electrode 4 Insulator layer 5 Gate electrode 6 Substrate 7 Protective layer 10A-10F Thin film transistor element 20 Organic solar cell element 21 Substrate 22 Anode 23 Power generation layer 24 Cathode 231 P-type layer 232 N-type layer 233 Buffer layer

Claims (12)

Following formula (1)

Wherein R ^{1 to} R ¹⁶ are each independently a hydrogen atom, a substituted or unsubstituted aryl group, a substituted or unsubstituted alkyl group, a halogen atom, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted alkylthio; A group, a substituted or unsubstituted alkylamino group, a substituted or unsubstituted dialkylamino group (the alkyl groups may be bonded to each other to form a cyclic structure containing a nitrogen atom), a substituted or unsubstituted alkylsulfonyl group, A substituted or unsubstituted trialkylsilyl group, a substituted or unsubstituted trialkylsilylethynyl group, a substituted or unsubstituted arylamino group, a substituted or unsubstituted diarylamino group, or a cyano group.
An organic compound represented by The organic compound according to claim 1,
R ^{1 to} R ⁴ and R ^{9 to} R ¹² are each independently a hydrogen atom, a substituted or unsubstituted aryl group, or a substituted or unsubstituted alkyl group,
An organic compound in which R ^{5 to} R ⁸ and R ^{13 to} R ¹⁶ are hydrogen atoms. An organic compound according to claim 2,
An organic compound in which R ^{1 to} R ⁴ and R ^{9 to} R ¹² are each independently a hydrogen atom or a substituted or unsubstituted alkyl group. The organic compound according to claim 3,
An organic compound in which R ^{1 to} R ⁴ and R ^{9 to} R ¹² are each independently a hydrogen atom or an unsubstituted alkyl group having 1 to 3 carbon atoms. An organic compound according to claim 4,
An organic compound in which R ^{1 to} R ⁴ and R ^{9 to} R ¹² are hydrogen atoms. An organic compound according to claim 4,
One of R ² and R ¹⁰ is an unsubstituted alkyl group having 1 to 3 carbon atoms, the other is a hydrogen atom or an unsubstituted alkyl group having 1 to 3 carbon atoms, and R ¹ , R ³ , R ⁴ , R ⁹ , R ¹¹ and R ¹² are hydrogen atoms, or one of R ³ and R ¹¹ is an unsubstituted alkyl group having 1 to 3 carbon atoms and the other is a hydrogen atom or 1 to 3 carbon atoms An organic compound which is an unsubstituted alkyl group and R ¹ , R ² , R ⁴ , R ⁹ , R ¹⁰ and R ¹² are hydrogen atoms.   The organic-semiconductor material containing the organic compound as described in any one of Claims 1 thru | or 6.   An organic thin film comprising the organic semiconductor material according to claim 7.   An organic electronic device comprising the organic semiconductor material according to claim 7. An organic electronic device according to claim 9,
Organic electronic devices that are thin film transistor elements, organic photoelectric conversion elements, organic solar cell elements, organic EL elements, organic light emitting transistor elements, or organic semiconductor laser elements. The organic electronic device according to claim 10,
An organic electronic device which is a thin film transistor element, an organic photoelectric conversion element, or an organic solar cell element. An organic electronic device according to claim 10 or 11,
Organic electronic devices that are thin film transistor elements.

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