JPWO2015133402A1 - Organic transistor - Google Patents

Abstract

An insulating layer on a substrate, a source electrode and a drain electrode spaced apart from each other on one side of the insulating layer, a gate electrode on the other side of the insulating layer, a source electrode, a drain electrode, and an insulator An organic semiconductor material having a semiconductor active layer in contact with the layer, the substrate, the gate electrode, the insulator layer, and the semiconductor active layer having a laminated structure, the semiconductor active layer being a condensed aromatic compound, and As component A, an organic transistor containing 0.1 to 10 ppm of an ionic substance, water, oxygen, and 0.5 to 4000 ppm of an organic semiconductor material and a compound having the same aromatic structure has carrier mobility, Any of carrier mobility variation, threshold voltage change after repeated driving, and threshold voltage change variation after repeated driving is improved.

Description

  The present invention relates to an organic transistor. More specifically, the present invention relates to an organic transistor in which any of carrier mobility, carrier mobility variation, threshold voltage change after repeated driving, and threshold voltage change variation after repeated driving is improved.

Devices using organic semiconductor materials are attracting a great deal of interest because they are expected to have various advantages over conventional devices using inorganic semiconductor materials such as silicon. Examples of a device using an organic semiconductor material include a photoelectric conversion element such as an organic thin-film solar cell and a solid-state imaging device using the organic semiconductor material as a photoelectric conversion material, and non-light-emitting properties (in this specification, “non-light-emitting properties”). "Means a luminous efficiency of 1 lm / W or less when a current is passed through the device at room temperature and a current density of 0.1 mW / cm ^{2 in} the atmosphere. An organic transistor (also referred to as an organic thin film transistor) of an organic transistor (which may be referred to as an organic thin film transistor) may be mentioned as an organic semiconductor device excluding a light emitting organic semiconductor device such as an electroluminescent element. A device using an organic semiconductor material may be capable of manufacturing a large-area element at a lower temperature and lower cost than a device using an inorganic semiconductor material. Furthermore, since the material characteristics can be easily changed by changing the molecular structure, there are a wide variety of materials, and it is possible to realize functions and elements that could not be achieved with inorganic semiconductor materials.

Organic transistors are expected as a future semiconductor technology because the semiconductor active layer can be formed with a simple device such as an under-air coating system, but on the other hand, the film forming environment is not under vacuum, Since it is not easy to purify, it is known that impurities are mixed in the semiconductor active layer, and a method for improving the characteristics of the organic transistor by reducing the amount of impurities is known. For example, in Patent Document 1, when benzothienobenzothiophene is used as a semiconductor material and the impurity is a hydrazone compound of the semiconductor material body, a semiconductor active layer is formed by applying a semiconductor / insulating polymer mixture to form two layers of semiconductor / insulating polymer. It is described that deterioration of characteristics due to impurities is reduced by adopting a structure.
Patent Document 2 describes that impurities in an organic film such as an organic semiconductor film can be reduced by performing a cleaning process with a cleaning solution after the organic semiconductor film is formed. However, Patent Document 2 does not have a detailed description of the specific cleaning in the examples.
In Patent Document 3, when a liquid crystalline organic semiconductor material is used as a semiconductor material and the impurity is a thiophene-based material, by removing the impurity by electrophoresis, an electronic conductivity characteristic inherently possessed by the liquid crystal system is effectively reduced. It is described that it can be expressed.
Patent Document 4 describes that an organic semiconductor material made of a π-conjugated polymer and containing 100 ppm or less of impurities contains a leakage current and suppresses the occurrence of a good on-off ratio. . In particular, Patent Document 4 mentions metal ions as impurities.
Patent Document 5 describes a method of performing recrystallization using concentration during film formation. Specifically, an organic semiconductor film exhibiting high mobility is formed by a method in which a condensed polycyclic aromatic compound solution is placed on a base at 60 to 230 ° C. and a condensed polycyclic aromatic compound film is formed by concentration. It is described to provide.

  On the other hand, in Patent Document 6, by using a condensed polycyclic aromatic compound having a specific structure as an organic semiconductor material of a semiconductor active layer, it can be produced by a coating method or the like, and semiconductor characteristics such as excellent carrier mobility. And providing a practical organic transistor having excellent stability.

JP2013-254874A JP 2010-182992 A Japanese Patent No. 4883381 JP 2004-83650 A Japanese Patent No. 4783282 Japanese Patent No. 4581062

Under such circumstances, when the present inventor examined an organic transistor using a semiconductor active layer described in these documents, it was found that further improvement in characteristics was required.
In particular, it has been found that the organic transistor using the organic semiconductor material described in Patent Document 4 has low mobility. Moreover, it turned out that the organic transistor of patent document 6 has a large variation in performance.

Furthermore, when the present inventor examined the organic transistor using the semiconductor active layer described in these documents, it was also clarified by the present inventors that the change in the threshold voltage becomes large when it is repeatedly driven. became. When the change in the threshold voltage increases, there is a problem that the reliability as a transistor is lowered and the semiconductor device cannot be used for a long time.
It was also found that the variation in threshold voltage after repeated driving has a large variation in performance from element to element.

  Therefore, the present inventor has made studies in order to solve such problems of the conventional technology. The problem to be solved by the present invention is to provide an organic transistor in which any of carrier mobility, carrier mobility variation, threshold voltage change after repeated driving, and threshold voltage change variation after repeated driving is improved. .

As a result of diligent studies to solve the above problems, it was common sense that the semiconductor active layer has better performance if there are few impurities. It has been found that any one of mobility, carrier mobility variation, threshold voltage change after repeated driving, and threshold voltage change variation after repeated driving is improved, and the present invention has been achieved.
The present invention, which is a specific means for solving the above problems, has the following configuration.

一般式１中、
Ａ^１、Ｂ^１およびＣ^１はそれぞれ独立にベンゼン環、アゾール環、フラン環またはチオフェン環であり、複数のＢ^１は同一であっても異なってもよい；
Ｒ^１１およびＲ^１２はそれぞれ独立にアルキル基、アルケニル基、アルキニル基、アリール基またはヘテロアリール基であり；
Ｒ^１１とＡ^１、または、Ｒ^１２とＣ^１は、それぞれ独立に酸素原子、硫黄原子、二価の置換アミノ基、カルボニル基、スルホキシド基、スルホン基およびこれらの組み合わせのいずれかを介して結合してもよい；
ｎ１は１〜５の整数である；
ｎ１１およびｎ１２はそれぞれ独立に１〜３の整数である。
［５］ ［４］に記載の有機トランジスタは、成分Ａが下記一般式３で表される化合物であることが好ましい；
一般式３

一般式３中、
Ａ^３、Ｂ^３およびＣ^３はそれぞれ独立にベンゼン環、アゾール環、フラン環またはチオフェン環であり、複数のＢ^３は同一であっても異なってもよい；
Ｒ^３１はアルキル基、アルケニル基、アルキニル基、アリール基またはヘテロアリール基であり；
Ｒ^３２は水素原子、ハロゲン原子、置換リン原子または置換酸素原子であり；
Ｒ^３１とＡ^３は、酸素原子、硫黄原子、二価の置換アミノ基、カルボニル基、スルホキシド基、スルホン基およびこれらの組み合わせのいずれかを介して結合してもよい；
ｎ３は１〜５の整数である；
ｎ３１およびｎ３２はそれぞれ独立に１〜３の整数である。
［６］ ［１］〜［３］のいずれか一つに記載の有機トランジスタは、有機半導体材料が下記一般式２で表される縮環芳香族化合物であることが好ましい；
一般式２

一般式２中、
Ａ^２およびＢ^２はそれぞれ独立に炭素数６〜１４の芳香族炭化水素環または炭素数４〜１２の芳香族ヘテロ環であり；
Ｒ^２１およびＲ^２２はそれぞれ独立にアルキル基、アルケニル基、アルキニル基、アリール基またはヘテロアリール基であり；
Ｒ^２１とベンゼン環、または、Ｒ^２２とベンゼン環は、それぞれ独立に酸素原子、硫黄原子、二価の置換アミノ基、カルボニル基、スルホキシド基、スルホン基およびこれらの組み合わせを介して結合してもよい。
［７］ ［６］に記載の有機トランジスタは、成分Ａが下記一般式４で表される化合物であることが好ましい；
一般式４

一般式４中、
Ａ^４およびＢ^４はそれぞれ独立に炭素数６〜１４の芳香族炭化水素環、炭素数４〜１２の芳香族ヘテロ環であり；
Ｒ^４１はアルキル基、アルケニル基、アルキニル基、アリール基またはヘテロアリール基であり；
Ｒ^４１とベンゼン環は、酸素原子、硫黄原子、二価の置換アミノ基、カルボニル基、スルホキシド基、スルホン基およびこれらの組み合わせを介して結合してもよい；
Ｒ^４２は水素原子、ハロゲン原子、置換リン原子、置換酸素原子または有機半導体材料のＲ^２２と同一構造ではないアルキニル基である。
［８］ ［２］〜［７］のいずれか一つに記載の有機トランジスタは、成分Ａが有機半導体層に０．５〜５０ｐｐｍ含まれることが好ましい。
［９］ ［１］に記載の有機トランジスタは、成分Ａとして、イオン性物質を０．１〜１０ｐｐｍ含有することが好ましい。
［１０］ ［１］に記載の有機トランジスタは、成分Ａとして、水または酸素を含有することが好ましい。
［１１］ ［１０］に記載の有機トランジスタは、少なくとも１時間以上、酸素含率２５％以下、かつ、相対湿度１０％以下のガス雰囲気下で、保管されてなることが好ましい。[1] having an insulator layer on the substrate;
Having a source electrode and a drain electrode spaced from each other on one side of the insulator layer;
Having a gate electrode on the other side of the insulator layer;
Having a semiconductor active layer in contact with a source electrode, a drain electrode and an insulator layer;
The substrate, gate electrode, insulator layer, and semiconductor active layer are stacked organic transistors,
An organic semiconductor material in which the semiconductor active layer is a condensed aromatic compound, and
An organic transistor containing, as Component A, 0.1 to 10 ppm of an ionic substance, water, oxygen, and 0.5 to 4000 ppm of an organic semiconductor material and a compound having the same aromatic structure.
[2] The organic transistor according to [1] preferably contains 0.5 to 4000 ppm of a fused aromatic compound having the same aromatic structure as the organic semiconductor material as component A.
[3] In the organic transistor according to [1] or [2], the organic semiconductor material is preferably a condensed aromatic compound including a thiophene ring in the condensed ring.
[4] In the organic transistor according to any one of [1] to [3], the organic semiconductor material is preferably a condensed aromatic compound represented by the following general formula 1;
General formula 1

In general formula 1,
A ¹ , B ¹ and C ¹ are each independently a benzene ring, an azole ring, a furan ring or a thiophene ring, and a plurality of B ¹ may be the same or different;
R ¹¹ and R ¹² are each independently an alkyl group, alkenyl group, alkynyl group, aryl group or heteroaryl group;
R ¹¹ and A ¹ , or R ¹² and C ¹ are each independently bonded via any one of oxygen atom, sulfur atom, divalent substituted amino group, carbonyl group, sulfoxide group, sulfone group and combinations thereof You may;
n1 is an integer from 1 to 5;
n11 and n12 are each independently an integer of 1 to 3.
[5] In the organic transistor according to [4], component A is preferably a compound represented by the following general formula 3;
General formula 3

In general formula 3,
A ³ , B ³ and C ³ are each independently a benzene ring, an azole ring, a furan ring or a thiophene ring, and a plurality of B ³ may be the same or different;
R ³¹ is an alkyl group, an alkenyl group, an alkynyl group, an aryl group or a heteroaryl group;
R ³² is a hydrogen atom, a halogen atom, a substituted phosphorus atom or a substituted oxygen atom;
R ³¹ and A ³ may be bonded via any one of an oxygen atom, a sulfur atom, a divalent substituted amino group, a carbonyl group, a sulfoxide group, a sulfone group, and combinations thereof;
n3 is an integer from 1 to 5;
n31 and n32 are each independently an integer of 1 to 3.
[6] In the organic transistor according to any one of [1] to [3], the organic semiconductor material is preferably a condensed aromatic compound represented by the following general formula 2;
General formula 2

In general formula 2,
A ² and B ² are each independently an aromatic hydrocarbon ring having 6 to 14 carbon atoms or an aromatic heterocyclic ring having 4 to 12 carbon atoms;
R ²¹ and R ²² are each independently an alkyl group, alkenyl group, alkynyl group, aryl group or heteroaryl group;
R ²¹ and the benzene ring, or R ²² and the benzene ring may be bonded independently via an oxygen atom, a sulfur atom, a divalent substituted amino group, a carbonyl group, a sulfoxide group, a sulfone group, or a combination thereof. Good.
[7] In the organic transistor according to [6], component A is preferably a compound represented by the following general formula 4;
Formula 4

In general formula 4,
A ⁴ and B ⁴ are each independently an aromatic hydrocarbon ring having 6 to 14 carbon atoms and an aromatic heterocycle having 4 to 12 carbon atoms;
R ⁴¹ is an alkyl group, an alkenyl group, an alkynyl group, an aryl group or a heteroaryl group;
R ⁴¹ and the benzene ring may be bonded via an oxygen atom, a sulfur atom, a divalent substituted amino group, a carbonyl group, a sulfoxide group, a sulfone group, and combinations thereof;
R ⁴² is a hydrogen atom, a halogen atom, a substituted phosphorus atom, a substituted oxygen atom, or an alkynyl group that does not have the same structure as R ^{22 of the} organic semiconductor material.
[8] In the organic transistor according to any one of [2] to [7], component A is preferably contained in the organic semiconductor layer in an amount of 0.5 to 50 ppm.
[9] The organic transistor according to [1] preferably contains 0.1 to 10 ppm of an ionic substance as component A.
[10] The organic transistor according to [1] preferably contains water or oxygen as component A.
[11] The organic transistor according to [10] is preferably stored in a gas atmosphere having an oxygen content of 25% or less and a relative humidity of 10% or less for at least 1 hour.

  According to the present invention, it is possible to provide an organic transistor in which any of carrier mobility, carrier mobility variation, threshold voltage change after repeated driving, and threshold voltage change variation after repeated driving is improved.

FIG. 1 is a schematic view showing a cross section of an example of the structure of the organic transistor of the present invention. FIG. 2 is a schematic view showing a cross section of the structure of an organic transistor manufactured as an FET characteristic measurement substrate in the example.

Hereinafter, the present invention will be described in detail. The description of the constituent elements described below may be made based on representative embodiments and specific examples, but the present invention is not limited to such embodiments. In the present specification, a numerical range expressed using “to” means a range including numerical values described before and after “to” as a lower limit value and an upper limit value.
In the present invention, a hydrogen atom when used without being particularly distinguished in the description of each general formula represents that it also contains an isotope (such as a deuterium atom). Furthermore, the atom which comprises a substituent represents that the isotope is also included.
In the present invention, the “aromatic structure” refers to a structure having aromaticity in an organic compound. In order for a molecule to have aromaticity, it is necessary to satisfy the two conditions of being a cyclic (4n + 2) π electron system (Huckel rule) and having a planar structure.

[Organic transistor]
The organic transistor of the present invention has an insulator layer on a substrate, a source electrode and a drain electrode spaced apart from each other on one side of the insulator layer, a gate electrode on the other side of the insulator layer, and a source An organic transistor having a semiconductor active layer in contact with an electrode, a drain electrode, and an insulator layer, the substrate, the gate electrode, the insulator layer, and the semiconductor active layer being a laminated structure, and the semiconductor active layer being a condensed aromatic compound As an organic semiconductor material, component A contains 0.1 to 10 ppm of an ionic substance, water, oxygen, and 0.5 to 4000 ppm of an organic semiconductor material and any compound having the same aromatic structure.
With such a configuration, the organic transistor of the present invention is improved in any of carrier mobility, carrier mobility variation, threshold voltage change after repeated driving, and threshold voltage change variation after repeated driving.

The organic transistor of the present invention preferably has a small threshold voltage change after repeated driving. In order to reduce the threshold voltage change after repeated driving, HOMO of the organic semiconductor material is neither too shallow nor too deep, the chemical stability of the organic semiconductor material (particularly air oxidation resistance, redox stability), Thermal stability in the film state, high film density that is difficult for air and moisture to enter, film quality with few defects that are difficult to accumulate charges, and the like are necessary. That is, an organic transistor with a small threshold voltage change after repeated driving has a high chemical stability and film density in the semiconductor active layer, and can function effectively as a transistor for a long period of time.
In addition, the organic transistor of the present invention preferably has a small variation in threshold voltage change after repeated driving.

In addition, what is useful as an organic EL element material cannot immediately be said to be useful as a semiconductor material for organic transistors. This is because organic EL elements and organic transistors have different characteristics required for organic compounds. In an organic EL element, it is usually necessary to transport charges in the film thickness direction (usually several nm to several hundred nm), whereas in an organic transistor, a long distance between electrodes in the film surface direction (usually several μm to several hundred μm). It is necessary to transport charges (carriers). For this reason, the required carrier mobility is remarkably high. Therefore, as a semiconductor material for an organic transistor, an organic compound having high molecular order and high crystallinity is required. In order to develop high carrier mobility, the π conjugate plane is preferably upright with respect to the substrate. On the other hand, in order to increase the light emission efficiency, an organic EL element is required to have a high light emission efficiency and uniform light emission in the surface. In general, organic compounds with high crystallinity cause light emission defects such as in-plane electric field strength non-uniformity, light emission non-uniformity, and light emission quenching. High material is desired. For this reason, even if the organic compound constituting the organic EL element material is directly transferred to the organic semiconductor material, good transistor characteristics cannot be obtained immediately.
Similarly, a useful organic photoelectric conversion element cannot be immediately said to be useful as a semiconductor material for an organic transistor having a remarkably high carrier mobility.

  Hereinafter, preferred embodiments of the organic transistor of the present invention will be described.

<Organic semiconductor material which is a fused aromatic compound>
The organic transistor of this invention contains the organic-semiconductor material whose semiconductor active layer mentioned later is a condensed ring aromatic compound.

In the present specification, the “organic semiconductor material” is an organic material exhibiting semiconductor characteristics. Similar to semiconductors made of inorganic materials, there are p-type (hole-transporting) organic semiconductor materials that conduct holes as carriers and n-type (electron-transporting) organic semiconductor materials that conduct electrons as carriers.
The condensed ring aromatic compound that can be used in the present invention may be used as either a p-type organic semiconductor material or an n-type organic semiconductor material, but is more preferably used as a p-type. The ease of carrier flow in the organic semiconductor is represented by carrier mobility μ. The carrier mobility μ is preferably high, preferably 1 × 10 ⁻⁴ cm ² / Vs or more, more preferably 1 × 10 ⁻² cm ² / Vs or more, and 5 × 10 ⁻² cm ^2. / Vs or higher is particularly preferable, 1 × 10 ⁻¹ cm ² / Vs or higher is more preferable, and 2 × 10 ⁻¹ cm ² / Vs or higher is even more preferable. The carrier mobility μ can be obtained by characteristics when a field effect transistor (FET) element is manufactured or by a time-of-flight measurement (TOF) method.

  There is no restriction | limiting in particular as a condensed-ring aromatic structure of the condensed-ring aromatic compound which can be used for this invention, A well-known condensed-ring aromatic structure can be mentioned.

Among condensed ring aromatic structures, a condensed ring aromatic structure containing a benzene ring, an azole ring, a furan ring or a thiophene ring in the condensed ring is preferable.
The condensed aromatic compound that can be used in the present invention is more preferably a condensed aromatic compound in which the organic semiconductor material contains a thiophene ring in the condensed ring from the viewpoint of improving carrier mobility.
The condensed aromatic structure of the condensed aromatic compound that can be used in the present invention is a condensed aromatic structure represented by A ¹ , B ¹ and C ¹ and n1 in the general formula 1 described later, or particularly preferably condensed ring aromatic structure represented by a ² and B ² in the general formula 2.

  Preferred examples of the fused aromatic structure of the fused aromatic compound that can be used as the organic semiconductor material in the present invention are shown below. The condensed ring aromatic structure that can be used in the present invention should not be construed as being limited by these specific examples. In the condensed aromatic structure of the condensed aromatic compound, each aromatic ring or each aromatic hetero ring may have an arbitrary substituent, and examples of the substituent include a halogen atom. .

In the organic transistor of the present invention, the organic semiconductor material is preferably a condensed aromatic compound represented by the following general formula 1 or a condensed aromatic compound represented by the general formula 2.
Hereinafter, the condensed ring aromatic compound represented by the general formula 1 and the condensed ring aromatic compound represented by the general formula 2 will be described in this order.

一般式１中、
Ａ^１、Ｂ^１およびＣ^１はそれぞれ独立にベンゼン環、アゾール環、フラン環またはチオフェン環であり、複数のＢ^１は同一であっても異なってもよい；
Ｒ^１１およびＲ^１２はそれぞれ独立にアルキル基、アルケニル基、アルキニル基、アリール基またはヘテロアリール基であり；
Ｒ^１１とＡ^１、または、Ｒ^１２とＣ^１は、それぞれ独立に酸素原子、硫黄原子、二価の置換アミノ基、カルボニル基、スルホキシド基、スルホン基およびこれらの組み合わせのいずれかを介して結合してもよい；
ｎ１は１〜５の整数である；
ｎ１１およびｎ１２はそれぞれ独立に１〜３の整数である。(Condensed aromatic compound represented by general formula 1)
General formula 1

In general formula 1,
A ¹ , B ¹ and C ¹ are each independently a benzene ring, an azole ring, a furan ring or a thiophene ring, and a plurality of B ¹ may be the same or different;
R ¹¹ and R ¹² are each independently an alkyl group, alkenyl group, alkynyl group, aryl group or heteroaryl group;
R ¹¹ and A ¹ , or R ¹² and C ¹ are each independently bonded via any one of oxygen atom, sulfur atom, divalent substituted amino group, carbonyl group, sulfoxide group, sulfone group and combinations thereof You may;
n1 is an integer from 1 to 5;
n11 and n12 are each independently an integer of 1 to 3.

In general formula 1, A ¹ , B ¹ and C ¹ are preferably each independently a benzene ring, a furan ring or a thiophene ring, and more preferably a benzene ring or a thiophene ring. More preferably, at least one of A ¹ , B ¹ and C ¹ is a thiophene ring.
In general formula 1, A ¹ , B ¹ and C ¹ may have a further substituent, and examples of the substituent include a halogen atom, and a fluorine atom is preferable. In general formula 1, it is preferable that A ¹ , B ¹ and C ¹ have no further substituents.

In general formula 1, R ¹¹ and R ¹² are preferably each independently an alkyl group, an aryl group, or a heteroaryl group, and more preferably an alkyl group.
The alkyl group represented by R ¹¹ and R ¹² preferably has 1 to 30 carbon atoms, more preferably 3 to 18 carbon atoms, and particularly preferably 5 to 14 carbon atoms. The alkyl group represented by R ¹¹ and R ¹² may be linear, branched or cyclic, but is preferably linear or branched, and is linear. Is more preferable.
The alkenyl group represented by R ¹¹ and R ¹² preferably has 2 to 30 carbon atoms, more preferably 3 to 18 carbon atoms, and particularly preferably 5 to 14 carbon atoms.
The alkynyl group represented by R ¹¹ and R ¹² preferably has 2 to 30 carbon atoms, more preferably 3 to 18 carbon atoms, and particularly preferably 5 to 14 carbon atoms. The alkynyl group represented by R ¹¹ and R ¹² preferably further has a substituent, such as a trialkylsilyl group (preferably a silyl group trisubstituted with an alkyl group having 1 to 3 carbon atoms). A substituted or unsubstituted phenyl group, and a trialkylsilyl group is preferred.
The aryl group represented by R ¹¹ and R ¹² preferably has 6 to 30 carbon atoms, more preferably 6 to 14 carbon atoms, and particularly preferably a phenyl group.
The heteroaryl group represented by R ¹¹ and R ¹² preferably has 3 to 12 carbon atoms, more preferably 4 to 8 carbon atoms, particularly preferably 4 carbon atoms, and is a thienyl group. Is more particularly preferred.

In General Formula 1, R ¹¹ and A ¹ or R ¹² and C ¹ are each independently an oxygen atom, a sulfur atom, a divalent substituted amino group, a carbonyl group, a sulfoxide group, a sulfone group, or a combination thereof. You may combine through. That is, the bonding mode of R ¹¹ and A ¹ , or the bonding mode of R ¹² and C ¹ includes a single bond, an oxygen atom, a sulfur atom, a divalent substituted amino group, a carbonyl group, a sulfoxide group, a sulfone group, and these It is a combination. The bonding mode of R ¹¹ and A ¹ or the bonding mode of R ¹² and C ¹ is preferably a single bond, an oxygen atom or a carbonyl group, and more preferably a single bond.

  In general formula 1, n1 is preferably 1 to 4, and more preferably 2 to 4.

  In general formula 1, n11 and n12 are each independently preferably 1 or 2, and more preferably 1.

一般式２中、
Ａ^２およびＢ^２はそれぞれ独立に炭素数６〜１４の芳香族炭化水素環または炭素数４〜１２の芳香族ヘテロ環であり；
Ｒ^２１およびＲ^２２はそれぞれ独立にアルキル基、アルケニル基、アルキニル基、アリール基またはヘテロアリール基であり；
Ｒ^２１とベンゼン環、または、Ｒ^２２とベンゼン環は、それぞれ独立に酸素原子、硫黄原子、二価の置換アミノ基、カルボニル基、スルホキシド基、スルホン基およびこれらの組み合わせを介して結合してもよい。(Condensed aromatic compound represented by Formula 2)
In the organic transistor of the present invention, the organic semiconductor material is preferably a condensed aromatic compound represented by the following general formula 2.
General formula 2

In general formula 2,
A ² and B ² are each independently an aromatic hydrocarbon ring having 6 to 14 carbon atoms or an aromatic heterocyclic ring having 4 to 12 carbon atoms;
R ²¹ and R ²² are each independently an alkyl group, alkenyl group, alkynyl group, aryl group or heteroaryl group;
R ²¹ and the benzene ring, or R ²² and the benzene ring may be bonded independently via an oxygen atom, a sulfur atom, a divalent substituted amino group, a carbonyl group, a sulfoxide group, a sulfone group, or a combination thereof. Good.

In General Formula 2, A ² and B ² are preferably each independently an aromatic hydrocarbon ring having 6 to 14 carbon atoms, an aromatic hetero ring having 6 to 12 carbon atoms, an azole ring, a furan ring, or a thiophene ring. More preferably an aromatic hydrocarbon ring having 6 to 14 carbon atoms, an aromatic hetero ring having 6 to 12 carbon atoms, a furan ring or a thiophene ring, an aromatic hydrocarbon ring having 6 to 14 carbon atoms, It is particularly preferably a 6-12 aromatic heterocycle or a thiophene ring, more preferably a C6-C14 aromatic hydrocarbon ring or a C6-C12 aromatic heterocycle, more preferably a carbon number. Even more preferred is a 6-14 aromatic hydrocarbon ring.
As the aromatic hydrocarbon ring having 6 to 14 carbon atoms represented by A ² and B ² , a benzene ring and a naphthylene ring are particularly preferable, and a naphthylene ring is more particularly preferable.
The aromatic heterocycle having 4 to 12 carbon atoms represented by A ² and B ² is preferably an aromatic heterocycle having 6 to 12 carbon atoms, an azole ring, a furan ring, or a thiophene ring, and an aromatic hydrocarbon having 6 to 12 carbon atoms. Heterocycles are more preferred, aromatic heterocycles having 8 to 12 carbon atoms are particularly preferred, thienobenzene rings and thienothiophene rings are more preferred, and thienobenzene rings are even more particularly preferred.
In General Formula 2, A ² and B ² may have a further substituent, and examples of the substituent include a halogen atom. In general formula 2, it is preferable that A ² and B ² have no further substituents.

In general formula 2, R ²¹ and R ²² are each independently preferably an alkynyl group, an alkyl group, or an alkenyl group, and more preferably an alkynyl group.
The alkyl group represented by R ²¹ and R ²² preferably has 1 to 30 carbon atoms, more preferably 3 to 18 carbon atoms, and particularly preferably 4 to 14 carbon atoms. The alkyl group represented by R ²¹ and R ²² may be linear, branched or cyclic, but is preferably linear or branched, and is linear. Is more preferable.
The alkenyl group represented by R ²¹ and R ²² preferably has 2 to 30 carbon atoms, more preferably 3 to 18 carbon atoms, and particularly preferably 4 to 14 carbon atoms.
The alkynyl group represented by R ²¹ and R ²² preferably has 2 to 30 carbon atoms, more preferably 2 to 18 carbon atoms, and particularly preferably 2 to 14 carbon atoms. The alkynyl group represented by R ²¹ and R ²² preferably further has a substituent, such as a trialkylsilyl group (preferably a silyl group trisubstituted with an alkyl group having 1 to 3 carbon atoms). , A trialkylalkyl group (preferably a methyl group trisubstituted with an alkyl group having 1 to 3 carbon atoms) may be a substituted or unsubstituted phenyl group, and a trialkylsilyl group is preferred.
The aryl group represented by R ¹¹ and R ¹² preferably has 6 to 30 carbon atoms, more preferably 6 to 18 carbon atoms, and particularly preferably a phenyl group.
The heteroaryl group represented by R ¹¹ and R ¹² preferably has 2 to 12 carbon atoms, more preferably 3 to 8 carbon atoms, and particularly preferably 4 carbon atoms.

In General Formula 2, R ²¹ and the benzene ring, or R ²² and the benzene ring are each independently an oxygen atom, a sulfur atom, a divalent substituted amino group, a carbonyl group, a sulfoxide group, a sulfone group, and a combination thereof. May be combined. That is, the bonding mode of R ²¹ and the benzene ring, or the bonding mode of R ²² and the benzene ring includes a single bond, an oxygen atom, a sulfur atom, a divalent substituted amino group, a carbonyl group, a sulfoxide group, a sulfone group, and these It is a combination. The bonding mode between R ²¹ and the benzene ring or the bonding mode between R ²² and the benzene ring is more preferably a single bond.

(Specific compound examples of fused-ring aromatic compounds)
Specific examples of the condensed ring aromatic compound that can be used as the organic semiconductor material in the present invention are shown below.

Formula (X)

In general formula (X), R ^X1 , A ^x and R ^X2 have the structures shown in the following table.
In the following table, “*” represents a bonding position, Me represents a methyl group, Et represents an ethyl group, Ph represents a phenyl group, SiMe ₃ represents a triethylsilyl group, and SiEt ₃ represents a triethylsilyl group. .

The condensed aromatic condensed ring aromatic compound may have a repeating structure, and may be a low molecule or a polymer. When the condensed aromatic condensed ring aromatic compound is a low molecular weight compound, the molecular weight is preferably 3000 or less, more preferably 2000 or less, further preferably 1000 or less, and 850 or less. Is particularly preferred. It is preferable to make the molecular weight not more than the above upper limit value because the solubility in a solvent can be increased.
On the other hand, from the viewpoint of film quality stability of the film, the molecular weight is preferably 400 or more, more preferably 450 or more, and further preferably 500 or more.
In the case where the condensed aromatic condensed ring aromatic compound is a polymer compound having a repeating structure, the weight average molecular weight is preferably 30,000 or more, more preferably 50,000 or more, and 100,000 or more. More preferably it is. When the condensed aromatic compound is a polymer compound having a repeating structure, the intermolecular interaction can be increased and high mobility can be obtained by setting the weight average molecular weight to the above lower limit or more. Therefore, it is preferable.
Examples of the polymer compound having a repeating structure include a π-conjugated polymer in which a condensed aromatic condensed ring aromatic compound represents at least one arylene group or heteroarylene group (thiophene, bithiophene) and exhibits a repeating structure, A pendant polymer in which an aromatic fused aromatic compound is bonded to a polymer main chain via a side chain is exemplified, and the polymer main chain is preferably polyacrylate, polyvinyl, polysiloxane, etc., and the side chain is An alkylene group, a polyethylene oxide group and the like are preferable.

Fused aromatic condensed ring aromatic compounds are disclosed in JP2013-254874A, JP2010-182992A, JP4883381, JP200483650A, JP4783282, JP4581062, and It can synthesize | combine according to each literature as described in the below-mentioned Example.
Any reaction conditions may be used in the synthesis of the fused-ring aromatic fused-ring aromatic compound. Any solvent may be used as the reaction solvent. In order to promote the ring formation reaction, it is preferable to use an acid or a base, and it is particularly preferable to use a base. The optimum reaction conditions vary depending on the structure of the target compound.

  Synthetic intermediates having various substituents can be synthesized by combining known reactions. Each substituent may be introduced at any intermediate stage. After the synthesis of the intermediate, it is preferable to purify by sublimation purification after purification by column chromatography, recrystallization or the like. By sublimation purification, not only can organic impurities be separated, but inorganic salts and residual solvents can be effectively removed.

<Component A>
The organic transistor of the present invention is composed of a compound having the same aromatic structure as 0.1 to 10 ppm of an ionic substance, water, oxygen, and 0.5 to 4000 ppm of an organic semiconductor material as a component A in a semiconductor active layer described later. Contains either.
Among these components A, in the organic transistor of the present invention, the semiconductor active layer has 0.1 to 10 ppm of ionic substance and 0.5 to 4000 ppm of organic semiconductor material having the same aromatic structure as component A. It is preferable to contain any of the aromatic compounds, and it is more preferable that the component A contains a condensed aromatic compound having the same aromatic structure as that of the organic semiconductor material of 0.5 to 4000 ppm.
Hereinafter, preferred embodiments of Component A will be described.

(Fused-ring aromatic compounds with the same aromatic structure as organic semiconductor materials)
The case where the above-mentioned component A contained in the semiconductor active layer is a condensed ring aromatic compound having the same aromatic structure as the organic semiconductor material will be described. In this case, because of these structural similarities, the component A is adsorbed on the crystal surface of the organic semiconductor material, and the crystal size can be made uniform by controlling the crystal growth rate. In addition, it is considered that the variation in threshold voltage change after repeated driving is stabilized.
The content of the condensed aromatic compound having the same aromatic structure as that of the organic semiconductor material as the component A described above contained in the semiconductor active layer is preferably 0.5 to 4000 ppm, preferably 0.5 to 500 ppm. Is more preferable, and 0.5 to 50 ppm is particularly preferable.
In the semiconductor active layer, the content of the condensed aromatic compound having the same aromatic structure as the organic semiconductor material as the component A described above is 0.5% from the viewpoint of improving variation in threshold voltage change after repeated driving. More preferably, it is -5 ppm, and it is still more especially preferable that it is 0.5-1 ppm.
On the other hand, the content of the condensed aromatic compound having the same aromatic structure as the organic semiconductor material as the component A in the semiconductor active layer is 1.5 to 50 ppm from the viewpoint of improving the carrier mobility variation. Is more particularly preferred, and even more particularly preferred is 5 to 50 ppm.

  A method for controlling the content of the condensed ring aromatic compound having the same aromatic structure as that of the organic semiconductor material as component A contained in the semiconductor active layer is not particularly limited, but known methods such as preparative chromatography And a method of purifying the synthesized organic semiconductor material to obtain a fraction of the content of the condensed aromatic compound having the same aromatic structure as that of the desired organic semiconductor material.

In Component A, which is a condensed ring aromatic compound having the same aromatic structure as the organic semiconductor material, there is no particular limitation on the aromatic structure that is the same as the organic semiconductor material, but the condensed ring of the above-mentioned condensed ring aromatic compound is not limited. Aromatic structures can be mentioned. The preferred range of the aromatic structure that is the same as the organic semiconductor material is the same as the preferred range of the fused aromatic structure of the above-mentioned fused aromatic compound.
The aromatic structure that is the same as the organic semiconductor material that can be used in the present invention is a condensed aromatic structure represented by A ¹ , B ¹ and C ¹ and n1 in the general formula 3 described later, or a general structure described later. A condensed aromatic structure represented by A ² and B ² in Formula 4 is particularly preferable.

一般式３中、
Ａ^３、Ｂ^３およびＣ^３はそれぞれ独立にベンゼン環、アゾール環、フラン環またはチオフェン環であり、複数のＢ^３は同一であっても異なってもよい；
Ｒ^３１はアルキル基、アルケニル基、アルキニル基、アリール基またはヘテロアリール基であり；
Ｒ^３２は水素原子、ハロゲン原子、置換リン原子または置換酸素原子であり；
Ｒ^３１とＡ^３は、酸素原子、硫黄原子、二価の置換アミノ基、カルボニル基、スルホキシド基、スルホン基およびこれらの組み合わせのいずれかを介して結合してもよい；
ｎ３は１〜５の整数である；
ｎ３１およびｎ３２はそれぞれ独立に１〜３の整数である。In the organic transistor of the present invention, when the organic semiconductor material is a condensed aromatic compound represented by the above general formula 1, the component A which is a condensed aromatic compound having the same aromatic structure as the organic semiconductor material is A compound represented by the following general formula 3 is preferable.
General formula 3

In general formula 3,
A ³ , B ³ and C ³ are each independently a benzene ring, an azole ring, a furan ring or a thiophene ring, and a plurality of B ³ may be the same or different;
R ³¹ is an alkyl group, an alkenyl group, an alkynyl group, an aryl group or a heteroaryl group;
R ³² is a hydrogen atom, a halogen atom, a substituted phosphorus atom or a substituted oxygen atom;
R ³¹ and A ³ may be bonded via any one of an oxygen atom, a sulfur atom, a divalent substituted amino group, a carbonyl group, a sulfoxide group, a sulfone group, and combinations thereof;
n3 is an integer from 1 to 5;
n31 and n32 are each independently an integer of 1 to 3.

Preferred ranges of A ³ , B ³ and C ^{3 in} the general formula ³ are the same as the preferred ranges of A ¹ , B ¹ and C ¹ in the general formula 1.
The preferred range of R ³¹ in general formula 3 is the same as the preferred range of R ¹¹ in general formula 1.
The preferable range of the bonding mode of R ³¹ and A ³ in the general formula 3 is the same as the preferable range of the bonding mode of R ¹¹ and A ¹ in the general formula 1.
The preferred range of n3 in general formula 3 is the same as the preferred range of n1 in general formula 1.
The preferable range of n31 in the general formula 3 is the same as the preferable range of n11 in the general formula 1.

In the general formula 3, R ³² is a hydrogen atom, a halogen atom, a substituted phosphorus atom or a substituted oxygen atom, preferably a hydrogen atom, a halogen atom or a substituted oxygen atom, more preferably a hydrogen atom.
Examples of the halogen atom represented by R ³² include a chlorine atom, a bromine atom, and an iodine atom, and a chlorine atom or a bromine atom is preferable.
Examples of the substituted phosphorus atom represented by R ³² include a diphenylphosphino group, a di-t-butylphosphino group, and a diarylphosphino group.
Examples of the substituted oxygen atom represented by R ³² include a hydroxyl group, an alkoxy group (preferably an alkoxy group having 1 to 18 carbon atoms, more preferably a methyl group), and a perfluoroalkylsulfonyloxy group (preferably a trifluoromethylsulfonyloxy group). And a hydroxyl group, an alkoxy group, and a trifluoromethylsulfonyloxy group are preferable.

  In General Formula 3, n32 is an integer of 1 to 3, preferably 1 or 2, and more preferably 1.

一般式４中、
Ａ^４およびＢ^４はそれぞれ独立に炭素数６〜１４の芳香族炭化水素環または炭素数４〜１４の芳香族ヘテロ環であり；
Ｒ^４１はアルキル基、アルケニル基、アルキニル基、アリール基またはヘテロアリール基であり；
Ｒ^４１とベンゼン環は、酸素原子、硫黄原子、二価の置換アミノ基、カルボニル基、スルホキシド基、スルホン基およびこれらの組み合わせを介して結合してもよい；
Ｒ^４２は水素原子、ハロゲン原子、置換リン原子、置換酸素原子または有機半導体材料のＲ^２２と同一構造ではないアルキニル基である。In the organic transistor of the present invention, when the organic semiconductor material is a condensed aromatic compound represented by the above general formula 2, the component A which is a condensed aromatic compound having the same aromatic structure as the organic semiconductor material is It is preferable that it is a compound represented by the following general formula 4.
Formula 4

In general formula 4,
A ⁴ and B ⁴ are each independently an aromatic hydrocarbon ring having 6 to 14 carbon atoms or an aromatic heterocyclic ring having ^{4 to} 14 carbon atoms;
R ⁴¹ is an alkyl group, an alkenyl group, an alkynyl group, an aryl group or a heteroaryl group;
R ⁴¹ and the benzene ring may be bonded via an oxygen atom, a sulfur atom, a divalent substituted amino group, a carbonyl group, a sulfoxide group, a sulfone group, and combinations thereof;
R ⁴² is a hydrogen atom, a halogen atom, a substituted phosphorus atom, a substituted oxygen atom, or an alkynyl group that does not have the same structure as R ^{22 of the} organic semiconductor material.

The preferred ranges of A ⁴ and B ⁴ in the general formula 4 are the same as the preferred ranges of A ² and B ² in the general formula 2.
The preferable range of R ⁴¹ in the general formula 4 is the same as the preferable range of R ²¹ in the general formula 2.
The preferable range of the bonding mode between R ⁴¹ and the benzene ring in the general formula 4 is the same as the preferable range of the bonding mode between R ²¹ and the benzene ring in the general formula 2.

In the Formula 4, R ⁴² is a hydrogen atom, a halogen atom, substituted phosphorus atom, an alkynyl group is not a R ²² the same structure of the substituent oxygen atom, or an organic semiconductor material, and more preferably a hydrogen atom.
The halogen atom R ⁴² represents a chlorine atom, a bromine atom, it may be mentioned iodine atom, a chlorine atom or a bromine atom.
The substituted phosphorus atom R ⁴² represents, it can be cited diphenylphosphino group, di t- butylphosphino group, a diarylphosphino group.
The substituted oxygen atom R ⁴² represents a hydroxyl group, an alkoxy group (preferably an alkoxy group having 1 to 18 carbon atoms, more preferably methyl group), perfluoroalkyl sulfonyl group (preferably a trifluoromethylsulfonyloxy group) And a hydroxyl group, an alkoxy group, and a trifluoromethylsulfonyloxy group are preferable.
The alkynyl group that is not the same structure as R ^{22 of the} organic semiconductor material represented by R ⁴² is preferably an alkynyl group having 2 to 18 carbon atoms, more preferably an alkynyl group having 2 to 14 carbon atoms, and an alkynyl group having 2 carbon atoms. Particularly preferred. Alkynyl group R ²² and not the same structure of the organic semiconductor materials R ⁴² represents may have a substituent, but is preferably unsubstituted.

  Examples of condensed aromatic compounds having the same aromatic structure as the organic semiconductor material that can be used as Component A will be shown.

Formula (A)

In general formula (A), R ^A1 , A ^A and R ^A2 are structures shown in the following table.
In the following table, “*” represents a bonding position, Me represents a methyl group, Et represents an ethyl group, Ph represents a phenyl group, SiMe ₃ represents a triethylsilyl group, and SiEt ₃ represents a triethylsilyl group. .

(Ionic substances)
The case where the above-described component A contained in the semiconductor active layer is an ionic substance will be described. In this case, it is considered that the carrier mobility variation is stabilized because convergence to a state where the amount of carrier scattering is small, and the variation in threshold voltage after repeated driving is stabilized because convergence to a state where the amount of doping is small occurs. I think that.
In the organic transistor of the present invention, the semiconductor active layer preferably contains 0.1 to 10 ppm of ionic substance as component A, more preferably 0.3 to 5 ppm of ionic substance. An embodiment containing ˜4 ppm of ionic material is particularly preferred.
When there are a plurality of ionic substances as component A contained in the semiconductor active layer, the total content of the ionic substances as the component A is within the above range. It is preferable.

  Although there is no restriction | limiting in particular as a method to control content of the ionic substance as the component A contained in a semiconductor active layer, The method of refine | purifying an organic semiconductor material using well-known purification methods, such as column chromatography, etc. Can be mentioned.

  Although there is no restriction | limiting in particular as an ionic substance, Sodium ion, potassium ion, magnesium ion, zinc ion, iron ion, palladium ion, platinum ion, gold ion, cesium ion etc. can be mentioned.

(Water, oxygen)
The case where the above-mentioned component A contained in the semiconductor active layer is either water or oxygen will be described. In this case, it is considered that the carrier mobility variation is stabilized because convergence to a state where the trap amount is small, and the variation in threshold voltage after repeated driving is stabilized because convergence to a state where the amount of doping is small occurs. Conceivable.
In the organic transistor of the present invention, an embodiment in which the semiconductor active layer contains either water or oxygen as the component A is preferable.
In the embodiment in which the semiconductor active layer contains water as component A, the semiconductor active layer preferably contains 0.1 to 10 ppm of water as component A, more preferably contains 0.3 to 5 ppm, and contains 0.5 to 4 ppm. Is particularly preferred.
In an embodiment in which the semiconductor active layer contains oxygen as component A, the semiconductor active layer preferably contains 0.1 to 10 ppm, more preferably 0.3 to 5 ppm, and more preferably 0.5 to 4 ppm. Is particularly preferred.

  Although there is no restriction | limiting in particular as a method of controlling either water and oxygen content as the component A contained in a semiconductor active layer, The method of storing in a specific gas atmosphere etc. can be mentioned. In the organic transistor of the present invention, when the semiconductor active layer contains either water or oxygen as component A, the organic transistor is at least 1 hour or more in a gas atmosphere having an oxygen content of 25% or less and a relative humidity of 10% or less. It is preferable to be stored.

<Structure of organic transistor>
The structure of the organic transistor of the present invention has an insulator layer on a substrate, a source electrode and a drain electrode separated from each other on one side of the insulator layer, and a gate electrode on the other side of the insulator layer. The organic transistor has a semiconductor active layer in contact with the source electrode, the drain electrode, and the insulator layer, and the substrate, the gate electrode, the insulator layer, and the semiconductor active layer are stacked.
The organic transistor of the present invention is preferably used as an organic field effect transistor (Field Effect Transistor, FET), and more preferably used as an insulated gate FET in which the gate-channel is insulated.
Hereinafter, although the aspect of the preferable structure of the organic transistor of this invention is demonstrated in detail using drawing, this invention is not limited to these aspects.

(Laminated structure)
There is no restriction | limiting in particular as a laminated structure of an organic field effect transistor, It can be set as the thing of various well-known structures.
As an example of the structure of the organic transistor of the present invention, a structure (bottom gate / top contact type) in which an electrode, an insulator layer, a semiconductor active layer (organic semiconductor layer), and two electrodes are arranged in this order on the upper surface of the lowermost substrate. ). In this structure, the electrode on the upper surface of the lowermost substrate is provided on a part of the substrate, and the insulator layer is disposed so as to be in contact with the substrate at a portion other than the electrode. Further, the two electrodes provided on the upper surface of the semiconductor active layer are arranged separately from each other.
The structure of the bottom gate / top contact type element is shown in FIG. FIG. 1 is a schematic view showing a cross section of an example of the structure of the organic transistor of the present invention. The organic transistor of FIG. 1 has a substrate 11 disposed in the lowermost layer, an electrode 12 is provided on a part of its upper surface, and further covers the electrode 12 and is in contact with the substrate 11 at a portion other than the electrode 12. 13 is provided. Further, the semiconductor active layer 14 is provided on the upper surface of the insulator layer 13, and the two electrodes 15a and 15b are disposed separately on a part of the upper surface.
In the organic transistor shown in FIG. 1, the electrode 12 is a gate, and the electrodes 15a and 15b are drains or sources, respectively. The organic transistor shown in FIG. 1 is an insulated gate FET in which a channel that is a current path between a drain and a source is insulated from a gate.

An example of the structure of the organic transistor of the present invention is a bottom gate / bottom contact type element.
The structure of the bottom gate / bottom contact type element is shown in FIG. FIG. 2 is a schematic view showing a cross section of the structure of an organic transistor manufactured as an FET characteristic measurement substrate in the example. In the organic transistor of FIG. 2, a substrate 31 is disposed in the lowermost layer, an electrode 32 is provided on a part of the upper surface thereof, and further, this insulator 32 is covered so as to be in contact with the substrate 31 at a portion other than the electrode 32. 33 is provided. Further, the semiconductor active layer 35 is provided on the upper surface of the insulator layer 33, and the electrodes 34 a and 34 b are below the semiconductor active layer 35.
In the organic transistor shown in FIG. 2, the electrode 32 is a gate, and the electrode 34a and the electrode 34b are a drain or a source, respectively. The organic transistor shown in FIG. 2 is an insulated gate FET in which a channel that is a current path between a drain and a source is insulated from a gate.

  As the structure of the organic transistor of the present invention, a top gate / top contact type element having an insulator and a gate electrode above the semiconductor active layer, and a top gate / bottom contact type element can also be preferably used.

(thickness)
When it is necessary to make the organic transistor of the present invention thinner, for example, the thickness of the entire transistor is preferably 0.1 to 0.5 μm.

(Sealing)
In order to shield the organic transistor element from the atmosphere and moisture and improve the storage stability of the organic transistor element, the entire organic transistor element is made of a metal sealing can, glass, an inorganic material such as silicon nitride, a polymer material such as parylene, It may be sealed with a low molecular material or the like.
Hereinafter, although the preferable aspect of each layer of the organic transistor of this invention is demonstrated, this invention is not limited to these aspects.

<Board>
(material)
The organic transistor of the present invention includes a substrate.
There is no restriction | limiting in particular as a material of a board | substrate, A well-known material can be used, For example, polyester films, such as a polyethylene naphthalate (PEN) and a polyethylene terephthalate (PET), a cycloolefin polymer film, a polycarbonate film, a triacetyl cellulose ( TAC) film, polyimide film, and those obtained by bonding these polymer films to ultrathin glass, ceramic, silicon, quartz, glass, and the like, and silicon is preferable.

<Electrode>
(material)
The organic transistor of the present invention includes electrodes such as a source electrode, a drain electrode, and a gate electrode.
Examples of the constituent material of the electrode include metal materials such as Cr, Al, Ta, Mo, Nb, Cu, Ag, Au, Pt, Pd, In, Ni, and Nd, alloy materials thereof, carbon materials, and conductivity. Any known conductive material such as a polymer can be used without particular limitation.

(thickness)
The thickness of the electrode is not particularly limited, but is preferably 10 to 50 nm.
There is no particular limitation on the gate width (or channel width) W and the gate length (or channel length) L, but the ratio W / L is preferably 10 or more, more preferably 20 or more.

<Insulating layer>
(material)
The material constituting the insulating layer is not particularly limited as long as the necessary insulating effect can be obtained. For example, fluorine polymer insulating materials such as silicon dioxide, silicon nitride, PTFE, CYTOP, polyester insulating materials, polycarbonate insulating materials, acrylic polymers Insulating material, epoxy resin insulating material, polyimide insulating material, polyvinylphenol resin insulating material, polyparaxylylene resin insulating material, and the like.
The upper surface of the insulating layer may be surface-treated. For example, an insulating layer whose surface is treated by applying hexamethyldisilazane (HMDS) or octadecyltrichlorosilane (OTS) to the silicon dioxide surface can be preferably used.

(thickness)
The thickness of the insulating layer is not particularly limited, but when thinning is required, the thickness is preferably 10 to 400 nm, more preferably 20 to 200 nm, and particularly preferably 50 to 200 nm. .

<Semiconductor active layer>
(material)
The organic transistor of the present invention includes an organic semiconductor material in which a semiconductor active layer is a condensed ring aromatic compound, and 0.1 to 10 ppm of an ionic substance, water, oxygen, and 0.5 to 4000 ppm of an organic semiconductor as component A Contains any of the compounds that have the same aromatic structure as the material.
The semiconductor active layer may be a layer composed of an organic semiconductor material that is a condensed ring aromatic compound and Component A, and further includes a polymer binder described below in addition to the organic semiconductor material that is a ring aromatic compound and Component A. It may be a layer. Moreover, the residual solvent at the time of film-forming may be contained.
The content of the polymer binder in the semiconductor active layer is not particularly limited, but is preferably used in the range of 0 to 95% by mass, more preferably in the range of 10 to 90% by mass, and still more preferably. It is used within a range of 20 to 80% by mass, and particularly preferably within a range of 30 to 70% by mass.

(thickness)
Although there is no restriction | limiting in particular in the thickness of a semiconductor active layer, When thinning is calculated | required, it is preferable to set thickness to 10-400 nm, It is more preferable to set it as 10-200 nm, It is especially preferable to set it as 10-100 nm. preferable.

Examples of the polymer binder include insulating polymers such as polystyrene, polycarbonate, polyarylate, polyester, polyamide, polyimide, polyurethane, polysiloxane, polysulfone, polymethyl methacrylate, polymethyl acrylate, cellulose, polyethylene, and polypropylene, and their co-polymers. Examples thereof include photoconductive polymers such as coalescence, polyvinyl carbazole, and polysilane, conductive polymers such as polythiophene, polypyrrole, polyaniline, and polyparaphenylene vinylene, and semiconductor polymers.
The polymer binder may be used alone or in combination.
In addition, the organic semiconductor material and the polymer binder may be uniformly mixed, or part or all of them may be phase-separated, but from the viewpoint of charge mobility, A structure in which the binder is phase-separated is most preferable because the binder does not hinder the charge transfer of the organic semiconductor.
In consideration of the mechanical strength of the film, a polymer binder having a high glass transition temperature is preferable, and in consideration of charge mobility, a polymer binder, a photoconductive polymer, or a conductive polymer having a structure containing no polar group is preferable.
Although there is no restriction | limiting in particular in the usage-amount of a polymer binder, In the organic-semiconductor film for nonluminous organic-semiconductor devices, Preferably it is used in the range of 0-95 mass%, More preferably, it exists in the range of 10-90 mass%. More preferably, it is used within the range of 20 to 80% by mass, and particularly preferably within the range of 30 to 70% by mass.

  Furthermore, when the condensed aromatic compound has the above-described structure, an organic film with good film quality can be obtained. Specifically, since the condensed aromatic compound has good crystallinity, a sufficient film thickness can be obtained, and the obtained organic semiconductor film for a non-light-emitting organic semiconductor device has a good quality.

(Film formation method)
Any method may be used to form the condensed aromatic compound on the substrate.
During film formation, the substrate may be heated or cooled, and the film quality and molecular packing in the film can be controlled by changing the temperature of the substrate. Although there is no restriction | limiting in particular as temperature of a board | substrate, It is preferable that it is between 0 degreeC and 200 degreeC, It is more preferable that it is between 15 degreeC-100 degreeC, It is especially between 20 degreeC-95 degreeC. preferable.
When the condensed aromatic compound is formed on the substrate, it can be formed by a vacuum process or a solution process, both of which are preferable.

  Specific examples of film formation by a vacuum process include physical vapor deposition methods such as vacuum deposition, sputtering, ion plating, molecular beam epitaxy (MBE), and chemical vapor deposition (CVD) such as plasma polymerization. ) Method, and it is particularly preferable to use a vacuum deposition method.

Here, film formation by a solution process refers to a method in which an organic compound is dissolved in a solvent that can be dissolved and a film is formed using the solution. Specifically, coating methods such as casting method, dip coating method, die coater method, roll coater method, bar coater method, spin coating method, ink jet method, screen printing method, gravure printing method, flexographic printing method, offset printing Various printing methods such as micro contact printing, micro contact printing, and ordinary methods such as Langmuir-Blodgett (LB) can be used. Casting, spin coating, ink jet, gravure printing, flexographic printing, offset It is particularly preferable to use a printing method or a microcontact printing method.
The organic semiconductor film for non-luminescent organic semiconductor device is preferably produced by a solution coating method. Moreover, when the organic semiconductor film for non-light-emitting organic semiconductor devices contains a polymer binder, the material for forming the layer and the polymer binder are dissolved or dispersed in an appropriate solvent to form a coating solution, and various coating methods can be used. Preferably it is formed.
Hereinafter, a coating solution for a non-light-emitting organic semiconductor device that can be used for film formation by a solution process will be described.

  When a film is formed on a substrate using a solution process, a material for forming the layer is selected from hydrocarbons such as hexane, octane, decane, toluene, xylene, mesitylene, ethylbenzene, decalin, and 1-methylnaphthalene. Solvents such as acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone and other ketone solvents such as dichloromethane, chloroform, tetrachloromethane, dichloroethane, trichloroethane, tetrachloroethane, chlorobenzene, dichlorobenzene, chlorotoluene and the like Solvent, for example, ester solvent such as ethyl acetate, butyl acetate, amyl acetate, for example, methanol, propanol, butanol, pentanol, hexanol, cyclohexanol, methyl Alcohol solvents such as rosolve, ethyl cellosolve, ethylene glycol, for example, ether solvents such as dibutyl ether, tetrahydrofuran, dioxane, anisole, such as N, N-dimethylformamide, N, N-dimethylacetamide, 1-methyl-2- An amide / imide solvent such as pyrrolidone, 1-methyl-2-imidazolidinone, a sulfoxide solvent such as dimethyl sulfoxide, a nitrile solvent such as acetonitrile) and / or water is dissolved or dispersed into a coating solution. A film can be formed by various coating methods. A solvent may be used independently and may be used in combination of multiple. Among these, hydrocarbon solvents, halogenated hydrocarbon solvents or ether solvents are preferable, toluene, xylene, mesitylene, tetralin, dichlorobenzene or anisole are more preferable, and toluene, xylene, tetralin and anisole are particularly preferable. The concentration of the condensed aromatic compound in the coating solution is preferably 0.1 to 80% by mass, more preferably 0.1 to 10% by mass, and particularly preferably 0.5 to 10% by mass. A film having an arbitrary thickness can be formed.

  In order to form a film by a solution process, it is necessary that the material is dissolved in the above-described solvent or the like, but it is not sufficient to simply dissolve the material. Usually, even a material for forming a film by a vacuum process can be dissolved in a solvent to some extent. However, in the solution process, there is a process in which a film is formed by evaporating the solvent after coating the material in a solvent, and many materials that are not suitable for solution process film formation have high crystallinity. It is difficult to form a good film due to inappropriate crystallization (aggregation) in the process. The condensed aromatic compound is also excellent in that such crystallization (aggregation) hardly occurs.

The coating solution for non-light-emitting organic semiconductor devices preferably contains a condensed ring aromatic compound and does not contain a polymer binder.
Moreover, the coating solution for nonluminous organic semiconductor devices may contain a condensed ring aromatic compound and a polymer binder. In this case, the material for forming the layer and the polymer binder can be dissolved or dispersed in the above-mentioned appropriate solvent to form a coating solution, and a film can be formed by various coating methods. The polymer binder can be selected from those described above.

  The features of the present invention will be described more specifically with reference to examples and comparative examples. The materials, amounts used, ratios, processing details, processing procedures, and the like shown in the following examples can be changed as appropriate without departing from the spirit of the present invention. Therefore, the scope of the present invention should not be construed as being limited by the specific examples shown below.

[Comparative Example 1]
(Synthesis)
Compound No. 4 in Synthesis Example 2 of Japanese Patent No. 4581062. With reference to the synthesis of 16, a comparative sample 1 containing the following compound 1 as a main component was synthesized according to the following procedure.

[Comparative Example 2]
To 1 g of the following raw material 2-1, 30 ml of THF / water mixed solvent, Organic Synthesis. 1993, No. 71, Item 89, 1-decene 9-BBN (9-borabiccyclo [3.3.1] nonane) adduct excess, PdCl ₂ (dppf) methylene chloride complex 0.02 equivalent, 1 equivalent of NaOH was added and stirred at 75 ° C. for 20 hours. The reaction solution was washed with water, concentrated, and purified by silica gel column chromatography (methylene chloride-hexane mixed solvent) to obtain a solid. Of these, 500 mg was added to 100 mg of Pd / C and 20 mL of a toluene-acetic acid mixed solvent, and the mixture was stirred for 14 hours under a hydrogen atmosphere. The reaction solution was filtered, concentrated, and purified by silica gel column chromatography (methylene chloride-hexane mixed solvent) to obtain a comparative sample 2 containing the following compound 2 as a main component.

[Comparative Example 3]
Organic Letters, 2005, Vol. 7, pp. 5301 synthesized with reference to the following raw material 3-1 100 g of methylene chloride was added to 3 g of the following material, BF ₃ ether complex solution was added, and the mixture was stirred at room temperature for 14 hours. As a result, a solid substance was obtained. This was washed with methanol, vacuum-dried, and then purified with a sublimation purification apparatus ALS-160H manufactured by ALS Technology to obtain a corresponding demethylated product. 100 ml of methylene chloride was added to 2 g of this demethylated product and cooled with ice water. An excess amount of trifluoromethanesulfonic acid and pyridine were added thereto, and the mixture was stirred for 14 hours. The reaction solution was washed with water and concentrated to obtain a solid. This was dissolved in methylene chloride, ethanol was added to precipitate crystals, and the corresponding triflate was obtained by filtration, washing, and drying. The obtained triflate body was reacted with a 9-BBN adduct of 1-hexyne in the same manner as in Comparative Sample 2 to obtain Comparative Sample 3 containing the following Compound 3 as a main component.

[Comparative Example 4]
The following raw material 4-1 was synthesized with reference to the description of WO2012 / 090462, and this was used as a raw material to convert the methoxy group to a heptyl group in the same manner as in Comparative Sample 3, and the corresponding following compound 4 was the main component. Comparative sample 4 was obtained.

[Comparative Example 5]
With reference to Organic Letters, 2002, Vol. 4, p. 15, a comparative sample 5 containing the following compound 5 as a main component was obtained.

[Comparative Example 6]
A comparative sample 6 containing the following compound 6 as a main component was obtained with reference to Journal OF THE American Chemical Society, 2005, 127, 4986.

[Production of organic transistors]
Comparative Samples 1 to 6 (1 mg each) and toluene (1 mL) were mixed and heated to 100 ° C. to obtain a coating solution for a non-luminescent organic semiconductor device. By casting this coating solution on a substrate for FET characteristic measurement heated to 90 ° C. in a nitrogen atmosphere, an organic semiconductor film for a non-light-emitting organic semiconductor device is formed, and Comparative Examples 1 to 6 for measuring FET characteristics are used. An organic transistor element was obtained. As a substrate for FET characteristic measurement, a silicon substrate having a bottom gate / bottom contact structure with chromium / gold arranged in a comb shape as source and drain electrodes and SiO ₂ (film thickness 180 nm) as an insulator layer (see FIG. 2). A schematic diagram of the structure was used). Each substrate has two sets of 9 elements each consisting of a 3 × 3 combination of a gate width W = 100 μm, 200 μm, 400 μm, and a gate length L = 100 μm, 75 μm, 50 μm, and each substrate has 18 elements.
The obtained organic transistor element was made into the organic transistor of Comparative Examples 1-6.

(Evaluation)
The FET characteristics of the organic transistor elements of Comparative Examples 1 to 6 and each of the examples described later were measured at normal pressure and nitrogen using a semiconductor parameter analyzer (Agilent, 4156C) connected to a semi-auto prober (Vector Semicon, AX-2000). Under the atmosphere, the following characteristics were measured.
The results obtained are shown in the table below.

(A) Carrier mobility, carrier mobility variation A voltage of -70 V is applied between the source electrode and the drain electrode of each organic transistor element (FET element), and the gate voltage is changed in the range of 20 V to -100 V, thereby drain current The carrier mobility μ was calculated using the following formula representing I _d .
I _d = (w / 2L) μC _i (V _g −V _th ) ²
In the formula, L is the gate length, W is the gate width, C _i is the capacitance per unit area of the insulating layer, V _g is the gate voltage, and V _th is the threshold voltage. The average value of all elements on the substrate was defined as the average carrier mobility.
For each substrate, the difference between the 10th carrier mobility value from the top and the 10th carrier mobility value from the bottom of the values (total of 50) obtained for each element is taken as the data width, and the average of the data width The relative value with respect to the carrier mobility value was defined as carrier mobility variation.

(B) Threshold voltage change after repeated driving, threshold voltage variation variation after repeated driving A voltage of -70 V is applied between the source electrode and the drain electrode of each organic transistor element (FET element), and the gate voltage is +20 V to -100 V Sweep 100 times within the range of the threshold voltage _before and after the threshold voltage V (difference before the threshold voltage V _before repeated driving and after the threshold voltage V _after repeated driving, | _after V− _before V |) on the substrate. The average value of the average values of all elements was obtained. The smaller this value, the better.
For each substrate, the threshold voltage change value after the 10th repeated driving from the top of the values (50 total) obtained for each element and the threshold voltage change difference after the 10th repeated driving from the bottom are data. The average value of the data width and the relative value with respect to the threshold voltage change after repeated driving were defined as the variation in threshold voltage change after repeated driving.

[Example 1-1]
Comparative sample 1 was purified using a preparative chromatograph apparatus FR-360 manufactured by Yamazen Co., Ltd. using a hexane-methylene chloride mixed solvent as an eluent. Since fractions having different degrees of purification were obtained, each fraction was used as a sample of 1-1a, 1-1b, 1-1c, and 1-1d. Example 1-1a, Example 1-1b, and Example 1-1 for FET characteristics measurement were performed in the same manner as Comparative Sample 1 except that these 1-1a, 1-1b, 1-1c, and 1-1d samples were used. Organic transistor elements of Example 1-1c and Example 1-1d were obtained. The transistor characteristics of the organic transistor elements of these examples were evaluated in the same manner as in Comparative Example 1.
As a result, as shown in the table below, a large difference was observed regarding carrier mobility variation and threshold voltage variation variation after repeated driving. As a result of component analysis and identification of impurities in each fraction, it was found that the following specific compound 1A was included. Moreover, it turned out that a more favorable result is obtained when the content rate of the following specific compound 1A is below a fixed amount.
The content of the following specific compound 1A was determined by dissolving the organic semiconductor film for non-luminescent organic semiconductor devices used in each example in tetrahydrofuran for HPLC and using a high performance liquid chromatography prominence system manufactured by Shimadzu Corporation. The measurement was performed under the following measurement conditions.
Eluent: Tetrahydrofuran-water gradient, detection wavelength 254 nm, liquid feed rate 1.0 ml / min, analytical column: TSKel ODS-100Z manufactured by Tosoh Corporation.

The notation of relative carrier mobility in the above table is as follows.
A: 1.2 times the standard value (improvement)
B: 0.5 times or more and less than 1.2 times the reference value C: Less than 0.5 times the reference value

About the result of the said table | surface, it thinks as follows. Compound 1A, which is a specific impurity having the same aromatic structure as compound 1 which is the main component, is produced in the final step of the synthesis with respect to the reaction intermediate produced by oxidative addition of the reaction catalyst to the starting halogenated compound. It is thought that hydrogenation occurred as a side reaction. Other by-products in the coupling reaction are also formed at the same time, but other by-products are removed in the compound purification step. However, it is considered that the specific compound 1A having properties similar to those of the main component compound 1 and having the same aromatic structure remains.
The effect of the specific compound 1A on variation in carrier mobility and variation in threshold voltage after repeated driving is very similar in structure and properties to the main component, and therefore adsorbs on the crystal surface during crystal formation of the semiconductor layer. It is thought that there was an effect as.

[Example 1-2]
In Example 1-1, the same experiment as in Example 1-1 was performed except that comparative sample 1 was replaced with comparative sample 2, and fractions 1-2a, 1-2b, 1-2c and 1- Samples 2d were obtained, and organic transistor elements of Example 1-2a, Example 1-2b, Example 1-2c, and Example 1-2d for FET characteristic measurement using these samples were obtained. The transistor characteristics of the organic transistor elements of these examples were evaluated in the same manner as in Comparative Example 1. The results are shown below.
From the table below, there was a large difference regarding carrier mobility variation and threshold voltage variation variation after repeated driving. As a result of component analysis of each fraction and identification of impurities, it was found that the following specific compound 2A having the same aromatic structure as that of the main component compound 2 was included. Moreover, it turned out that a more favorable result is obtained when the content rate of the following specific compound 2A is below a fixed amount.
The content of the following specific compound 2A was measured in the same manner as the specific compound 1A.

The notation of relative carrier mobility in the above table is as follows.
A: 1.2 times the standard value (improvement)
B: 0.5 times or more and less than 1.2 times the reference value C: Less than 0.5 times the reference value

[Example 1-3]
In Example 1-1, the same experiment as in Example 1-1 was performed except that comparative sample 1 was replaced with comparative sample 3, and fractions 1-3a, 1-3b, 1-3c, and 1- 3d samples were obtained, and organic transistor elements of Example 1-3a, Example 1-3b, Example 1-3c, and Example 1-3d for FET characteristic measurement using these were obtained. The transistor characteristics of the organic transistor elements of these examples were evaluated in the same manner as in Comparative Example 1. The results are shown below.
From the table below, there was a large difference regarding carrier mobility variation and threshold voltage variation variation after repeated driving. As a result of component analysis and identification of impurities in each fraction, it was found that the following specific compound 3A having the same aromatic structure as that of the main component compound 3 was included. Moreover, it turned out that a more favorable result is obtained when the content rate of the following specific compound 3A is below a fixed amount.
The content of the following specific compound 3A was measured in the same manner as the specific compound 1A.

The notation of relative carrier mobility in the above table is as follows.
A: 1.2 times the standard value (improvement)
B: 0.5 times or more and less than 1.2 times the reference value C: Less than 0.5 times the reference value

[Example 1-4]
In Example 1-1, the same experiment as in Example 1-1 was performed except that Comparative Sample 1 was replaced with Comparative Sample 4, and fractions 1-4a, 1-4b, 1-4c, and 1- Samples 4d were obtained, and organic transistor elements of Examples 1-4a, 1-4b, 1-4c, and 1-4d for measuring FET characteristics using these samples were obtained. The transistor characteristics of the organic transistor elements of these examples were evaluated in the same manner as in Comparative Example 1. The results are shown below.
From the table below, there was a large difference regarding carrier mobility variation and threshold voltage variation variation after repeated driving. As a result of component analysis of each fraction and identification of impurities, it was found that the following specific compound 4A having the same aromatic structure as that of the main component compound 4 was included. Moreover, it turned out that a more favorable result is obtained when the content rate of the following specific compound 4A is below a fixed amount.
The content of the following specific compound 4A was measured in the same manner as the specific compound 1A.

The notation of relative carrier mobility in the above table is as follows.
A: 1.2 times the standard value (improvement)
B: 0.5 times or more and less than 1.2 times the reference value C: Less than 0.5 times the reference value

[Example 1-5]
In Example 1-1, the same experiment as in Example 1-1 was performed except that comparative sample 1 was replaced with comparative sample 5, and fractions 1-5a, 1-5b, 1-5c and 1- Samples 5d were obtained, and organic transistor elements of Examples 1-5a, 1-5b, 1-5c, and 1-5d for measuring FET characteristics using these samples were obtained. The transistor characteristics of the organic transistor elements of these examples were evaluated in the same manner as in Comparative Example 1. The results are shown below.
From the table below, there was a large difference regarding carrier mobility variation and threshold voltage variation variation after repeated driving. As a result of component analysis of each fraction and identification of impurities, it was found that the following specific compound 5A having the same aromatic structure as that of the main component compound 5 was included. Moreover, it turned out that a more favorable result is obtained when the content rate of the following specific compound 5A is below a fixed amount.
The content of the following specific compound 5A was measured in the same manner as the specific compound 1A.

The notation of relative carrier mobility in the above table is as follows.
A: 1.2 times the standard value (improvement)
B: 0.5 times or more and less than 1.2 times the reference value C: Less than 0.5 times the reference value

  In Example 1-5, the structure of the specific compound 5A was different from that of the specific compounds 1A to 4A included as specific impurities in Examples 1-1 to 1-4. This specific compound 5A can be presumed to be a compound formed by cleaving a C—Si bond, which is a relatively weak bond, during the reaction or purification.

[Example 1-6]
In Example 1-1, the same experiment as in Example 1-1 was performed except that comparative sample 1 was replaced with comparative sample 6, and fractions 1-6a, 1-6b, 1-6c and 1- Samples 6d were obtained, and organic transistor elements of Examples 1-6a, 1-6b, 1-6c, and 1-6d for measuring FET characteristics using these samples were obtained. The transistor characteristics of the organic transistor elements of these examples were evaluated in the same manner as in Comparative Example 1. The results are shown below.
From the table below, there was a large difference regarding carrier mobility variation and threshold voltage variation variation after repeated driving. As a result of component analysis and identification of impurities in each fraction, it was found that the following specific compound 6A having the same aromatic structure as that of the main component compound 6 was included. Moreover, it turned out that a more favorable result is obtained when the content rate of the following specific compound 6A is below a fixed amount.
The content of the following specific compound 6A was measured in the same manner as the specific compound 1A.

The notation of relative carrier mobility in the above table is as follows.
A: 1.2 times the standard value (improvement)
B: 0.5 times or more and less than 1.2 times the reference value C: Less than 0.5 times the reference value

[Example 2-1]
In order to investigate the influence of an ionic substance, the comparative sample 1 uses a commercially available column for glass chromatography, and the degree of purification is different using column chromatography using a chloroform-tetrahydrofuran-n-hexane gradient as an eluent. A sample was obtained. In particular, after the second round of purification, all instruments used were washed with dilute hydrochloric acid in advance and then washed with ultrapure.
The amount of the ionic substance in the comparative sample 1 and the sample of each purification number is obtained by ashing / dissolving the organic semiconductor film for the non-luminescent organic semiconductor device used in each example, and using ICP-MS HP7700 manufactured by Agilent. And quantified. Specifically, the total of sodium ions, potassium ions, and magnesium ions was determined in ppm.
An organic transistor element of Example 2-1 for measuring FET characteristics was obtained in the same manner as Comparative Examples 1 to 6 using Comparative Sample 1 except that these samples were used for purification. The transistor characteristics of the organic transistor elements of these examples were evaluated in the same manner as Comparative Sample 1.
In Example 2-1 and Examples 2-2 to 2-6, which will be described later, the carrier mobility itself varies depending on the compound that is the main component. Therefore, an unpurified comparative sample containing the corresponding compound that is the main component was used. The carrier mobility of the organic transistor element of Comparative Examples 1-6 was made into the reference value of the carrier mobility of the organic transistor element of each Example.

[Examples 2-2 to 2-6]
In Example 2-1, organic compounds of Examples 2-2 to 2-6 were used in the same manner as in Example 2-1, except that Comparative Samples 2 to 6 were used instead of Comparative Sample 1 and purification was performed twice. A transistor element was obtained.
The amount of the ionic substance in the samples with the number of purification times of 2 used in Comparative Samples 2 to 6 and Examples 2-2 to 2-6 was measured in the same manner as in Example 2-1.
The transistor characteristics of the organic transistor elements of these examples were evaluated in the same manner as Comparative Sample 1.
The obtained results are shown in the following table.

  From the above table, improvement in relative carrier movement is recognized with respect to the corresponding comparative examples in any of the examples. It can be seen that the content of the ionic substance is good around 1 ppm.

[Example 3-1]
In order to investigate the influence of water and oxygen, the organic transistor was stored for 24 hours and evaluated in a gas atmosphere as shown in the following table. The oxygen content is the relative amount (%) of oxygen in the gas atmosphere. The atmosphere gas was prepared by preparing a nitrogen-oxygen mixed gas using a gas cylinder and humidifying a certain amount thereof. The transistor was stored for 24 hours in a gas atmosphere.
Example 3-1a, Example 3-1b, and Example 3-1c for measuring FET characteristics were performed in the same manner as Comparative Examples 1 to 6 using Comparative Sample 1 except that these samples were used for each number of purification times. Thus, organic transistor elements of Example 3-1d, Example 3-1e, and Example 3-1f were obtained. The transistor characteristics of the organic transistor elements of these examples were evaluated in the same manner as Comparative Sample 1.
In Example 3-1 and Examples 3-2 to 3-6, which will be described later, the threshold voltage change itself after repeated driving varies depending on the compound that is the main component. The threshold voltage change after the repeated driving of the organic transistor elements of Comparative Examples 1 to 6 using the sample was used as a reference value for the threshold voltage change after the repeated driving of the organic transistor of each example.

[Examples 3-2 to 3-6]
In Example 3-1f, Comparative Samples 2 to 6 were used instead of Comparative Sample 1, and the others were the same as Example 3-1f, and the organic transistor elements of Examples 3-2 to 3-6 were obtained.
The transistor characteristics of the organic transistor elements of these examples were evaluated in the same manner as Comparative Sample 1.
The obtained results are shown in the following table.

From the above table, improvement in the threshold voltage change after repeated driving is recognized with respect to the corresponding comparative example in any of the examples.
It can be seen that the oxygen content in the gas atmosphere during storage of the organic transistor element is preferably lower.
It can be seen that a lower relative humidity in the gas atmosphere during storage of the organic transistor element is preferable.

  In addition, although quantification of the oxygen content and water content in the transistor active layer was examined, it was difficult to separate it from environmental factors and could not be carried out.

11 Substrate 12 Gate electrode 13 Insulator layer 14 Semiconductor active layer (organic material layer, organic semiconductor layer)
15a, 15b Source electrode and drain electrode 31 Substrate 32 Gate electrode 33 Insulator layer 34a, 34b Source electrode and drain electrode 35 Semiconductor active layer (organic material layer, organic semiconductor layer)

Claims (11)

Having an insulator layer on the substrate,
Having a source electrode and a drain electrode spaced from each other on one side of the insulator layer;
A gate electrode on the other side of the insulator layer;
A semiconductor active layer in contact with the source electrode, the drain electrode and the insulator layer;
The substrate, the gate electrode, the insulator layer and the semiconductor active layer are organic transistors having a laminated structure,
An organic semiconductor material in which the semiconductor active layer is a condensed ring aromatic compound, and
As the component A, an organic transistor containing 0.1 to 10 ppm of an ionic substance, water, oxygen, and 0.5 to 4000 ppm of the organic semiconductor material and any compound having the same aromatic structure.   The organic transistor according to claim 1, wherein the component A contains a condensed aromatic compound having the same aromatic structure as that of the organic semiconductor material in an amount of 0.5 to 4000 ppm.   The organic transistor according to claim 1, wherein the organic semiconductor material is a condensed aromatic compound containing a thiophene ring in the condensed ring. The organic transistor according to any one of claims 1 to 3, wherein the organic semiconductor material is a condensed aromatic compound represented by the following general formula 1:
General formula 1

In general formula 1,
A ¹ , B ¹ and C ¹ are each independently a benzene ring, an azole ring, a furan ring or a thiophene ring, and a plurality of B ¹ may be the same or different;
R ¹¹ and R ¹² are each independently an alkyl group, alkenyl group, alkynyl group, aryl group or heteroaryl group;
R ¹¹ and A ¹ , or R ¹² and C ¹ are each independently bonded via any one of oxygen atom, sulfur atom, divalent substituted amino group, carbonyl group, sulfoxide group, sulfone group and combinations thereof You may;
n1 is an integer from 1 to 5;
n11 and n12 are each independently an integer of 1 to 3. The organic transistor according to claim 4, wherein the component A is a compound represented by the following general formula 3;
General formula 3

In general formula 3,
A ³ , B ³ and C ³ are each independently a benzene ring, an azole ring, a furan ring or a thiophene ring, and a plurality of B ³ may be the same or different;
R ³¹ is an alkyl group, an alkenyl group, an alkynyl group, an aryl group or a heteroaryl group;
R ³² is a hydrogen atom, a halogen atom, a substituted phosphorus atom or a substituted oxygen atom;
R ³¹ and A ³ may be bonded via any one of an oxygen atom, a sulfur atom, a divalent substituted amino group, a carbonyl group, a sulfoxide group, a sulfone group, and combinations thereof;
n3 is an integer from 1 to 5;
n31 and n32 are each independently an integer of 1 to 3. The organic transistor according to any one of claims 1 to 3, wherein the organic semiconductor material is a condensed aromatic compound represented by the following general formula 2:
General formula 2

In general formula 2,
A ² and B ² are each independently an aromatic hydrocarbon ring having 6 to 14 carbon atoms or an aromatic heterocyclic ring having 4 to 12 carbon atoms;
R ²¹ and R ²² are each independently an alkyl group, alkenyl group, alkynyl group, aryl group or heteroaryl group;
R ²¹ and the benzene ring, or R ²² and the benzene ring may be bonded independently via an oxygen atom, a sulfur atom, a divalent substituted amino group, a carbonyl group, a sulfoxide group, a sulfone group, or a combination thereof. Good. The organic transistor according to claim 6, wherein the component A is a compound represented by the following general formula 4;
Formula 4

In general formula 4,
A ⁴ and B ⁴ are each independently an aromatic hydrocarbon ring having 6 to 14 carbon atoms or an aromatic heterocyclic ring having 4 to 12 carbon atoms;
R ⁴¹ is an alkyl group, an alkenyl group, an alkynyl group, an aryl group or a heteroaryl group;
R ⁴¹ and the benzene ring may be bonded via an oxygen atom, a sulfur atom, a divalent substituted amino group, a carbonyl group, a sulfoxide group, a sulfone group, and combinations thereof;
R ⁴² is a hydrogen atom, a halogen atom, a substituted phosphorus atom, a substituted oxygen atom, or an alkynyl group that does not have the same structure as R ^{22 of the} organic semiconductor material.   The organic transistor according to claim 2, wherein the component A is contained in the organic semiconductor layer in an amount of 0.5 to 50 ppm.   The organic transistor according to claim 1, wherein the component A contains 0.1 to 10 ppm of the ionic substance.   The organic transistor according to claim 1, wherein the component A contains water or oxygen.   The organic transistor according to claim 10, which is stored in a gas atmosphere having an oxygen content of 25% or less and a relative humidity of 10% or less for at least 1 hour or more.

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