KR102001624B1 - Nitrogen-containing aromatic compound, organic semiconductor material and organic electronic devices - Google Patents

Abstract

A nitrogen-containing heterocyclic compound having high charge transportability, solvent solubility, oxidation stability and good film-forming property, an organic semiconductor material containing the same, and an organic semiconductor device using the same are provided. The nitrogen-containing heterocyclic compound is represented by the following general formula (1), and the organic semiconductor material includes this nitrogen-containing heterocyclic compound. And an organic semiconductor device using the nitrogen-containing heterocyclic compound. The organic semiconductor device has an organic semiconductor material containing the nitrogen-containing heterocyclic compound as a thin film layer. Examples of organic electronic devices include organic field effect transistors, organic thin film solar cells, information tags, large area sensors such as electronic artificial skin sheets and sheet type scanners, liquid crystal displays, electronic paper, and organic EL panels.

Description

TECHNICAL FIELD [0001] The present invention relates to a nitrogen-containing aromatic compound, an organic semiconducting material, and an organic electronic device. BACKGROUND OF THE INVENTION < RTI ID =

The present invention relates to a novel nitrogen aromatic compound and an organic semiconductor material containing the same, an organic semiconductor film obtained using the organic semiconductor material, and an organic electronic device such as an organic thin film transistor.

Generally, in a semiconductor device using silicon of an inorganic semiconductor material, a high-temperature process and a high-vacuum process are required for forming the thin film. It is impossible to form a thin film on a plastic substrate or the like by requiring a high-temperature process, and it has been difficult to impart flexibility and lightness to a product including a semiconductor element. In addition, since a high-vacuum process is required, it is difficult to make a product including a semiconductor device large in size and low in cost.

Therefore, researches on organic electronic devices (for example, organic electroluminescence (organic EL) devices, organic thin film transistor devices, organic thin film photoelectric conversion devices, etc.) using organic semiconductor materials as organic electronic components have been studied. These organic semiconductor materials can be formed on a plastic substrate or the like because the temperature of the fabrication process can be remarkably reduced as compared with inorganic semiconductor materials. Further, by using an organic semiconductor material having a good film-forming property while being highly soluble in a solvent, it is possible to form a thin film by using a coating method which does not require a vacuum process, such as an inkjet apparatus As a result, it is expected that realization of large-sized and low-cost semiconductor devices using silicon as an inorganic semiconductor material is difficult. Since the organic semiconductor material is advantageous in terms of size, flexibility, weight, and cost as compared with an inorganic semiconductor material, applications to organic semiconductor products utilizing such characteristics, for example, information tags, Large-area sensors such as sheet and sheet type scanners, liquid crystal displays, electronic papers, displays such as organic EL panels, and the like.

Thus, a high charge mobility is required for an organic semiconductor material used in an organic electronic device in which a wide range of applications is expected. For example, since the organic thin film transistor directly affects the switching speed and the performance of the driving device, it is an essential task to improve the charge mobility for practical use. In addition, as described above, solvent solubility, oxidation stability, and good film formability (film formability) are required in order to enable the production of an organic semiconductor device by a coating method.

Particularly, a large amount of charge mobility can be regarded as a required characteristic for an organic semiconductor. From this point of view, recently, an organic semiconductor material having charge transportability comparable to amorphous silicon has been reported. For example, in an organic field effect transistor device (OFET) in which pentacene, which is a hydrocarbon-based acene type polycyclic aromatic molecule condensed in a linear form with five benzene rings, is used as an organic semiconductor material, an amorphous silicon Have been reported (Non-Patent Document 1). A method of forming pentacene crystals in a dilute solution of trichlorobenzene without using a vacuum evaporation method has also been proposed. However, the production method is difficult and a stable element has not been obtained (Patent Document 1). In the hydrocarbon-based polycyclic aromatic molecule such as pentacene, oxidation stability is also low.

Pentathienoacenes having a thiophene ring condensed therein have improved oxidation resistance as compared with pentacene. However, since the carrier mobility is low and multiple steps are required for its synthesis (see Non-Patent Document 2) it was not a material that is practically preferable.

Organic thin film solar cells formed by laminating organic semiconductor materials in a thin film form have been studied as a single layer film using merocyanine dye or the like as an organic semiconductor material at the beginning of development, Layer film having an n-type organic semiconductor layer for transporting electrons has been found to improve the conversion efficiency (photoelectric conversion efficiency) from an optical input to an electric output, a multilayer film has become mainstream. The organic semiconductor material used when the multilayered film began to be studied was copper phthalocyanine (CuPc) as the p-type organic semiconductor material layer and perylene imide (PTCBI) as the n-type organic semiconductor material layer. On the other hand, in an organic thin film solar cell using a polymer, a conductive polymer is used as a p-type organic semiconductor material, a fullerene (C60) derivative is used as an n-type organic semiconductor material, Called bulk heterostructure research has been carried out mainly to increase the heterointerface and improve the photoelectric conversion efficiency. The material system used here was mainly poly-3-hexylthiophene (P3HT) as the p-type organic semiconductor material and C60 derivative (PCBM) as the n-type organic semiconductor material.

In this organic thin-film solar cell, the materials of each layer have not progressed much since the beginning, and phthalocyanine derivatives, perylene imide derivatives and C60 derivatives are still used. However, the photoelectric conversion efficiency, which is the most important characteristic of the organic thin film solar cell, was not sufficient. In order to improve photoelectric conversion efficiency, an organic semiconductor material having a high charge mobility is required. In addition, in order to make a semiconductor device by the coating method as in the case of the above-described organic transistor, solvent availability, oxidation stability, and good film-forming property are required.

Therefore, in order to increase the photoelectric conversion efficiency, development of new materials replacing these conventional materials is being eagerly desired. For example, Patent Document 2 discloses an organic thin film solar cell using a compound having a fluoranthene skeleton, but does not give satisfactory photoelectric conversion efficiency.

WO2003 / 016599 Japanese Patent Application Laid-Open No. 2009-290091

Journal of Applied Physics, 92, 5259 (2002) Journal of the American Chemical Society, Vol. 127, 13281 (2005)

It is an object of the present invention to provide an organic electronic device obtained by using a novel nitrogen-containing aromatic compound, an organic semiconductor material containing the same, and an organic semiconductor material that can be used as an organic semiconductor material solving the problems of the above- .

The present inventors have intensively studied and found that a novel organic semiconductor material having high charge mobility, oxidation stability, and solvent solubility is found and used in an organic semiconductor device to find a high-performance organic electronic device device. The invention has arrived.

The present invention relates to a nitrogen-containing aromatic heterocyclic compound represented by the following general formula (1).

In formula (1), each R independently represents hydrogen, an aliphatic hydrocarbon group of 1 to 30 carbon atoms, an aromatic group of 3 to 50 carbon atoms, an aromatic substituted alkyl group of 4 to 60 carbon atoms, an aromatic substituted alkenyl group of 5 to 60 carbon atoms, And at least one of R represents an aromatic group having 3 to 50 carbon atoms, an aromatic substituted alkyl group having 4 to 60 carbon atoms, an aromatic substituted alkenyl group having 5 to 60 carbon atoms, or an aromatic substituted alkenyl group having 5 to 60 carbon atoms And a substituted alkynyl group. and n represents an integer of 0 to 4. n represents an integer of 1 to 4;

As the compound represented by the general formula (1), there is a compound represented by the following general formula (2).

In the formula (2), R has the same meaning as R in the general formula (1).

Another embodiment of the present invention is a nitrogen-containing aromatic heterocyclic compound represented by the following general formula (3).

Wherein X represents a halogen atom, a hydroxyl group, a boronic acid, a boronic acid ester, or a sulfonyl group. n has the same meaning as n in the general formula (1).

Another aspect of the present invention is a process for producing a nitrogen-containing aromatic heterocyclic compound represented by the above general formula (1), wherein the compound represented by the general formula (3) and the compound represented by the following general formula (4) to be.

In the formula (4), R is the same as R in the formula (1), and Y is a functional group which reacts with X to desorb.

Another embodiment of the present invention is an organic semiconductor material characterized by containing the compound represented by the above general formula (1).

Another aspect of the present invention is an organic semiconductor film characterized by containing the above organic semiconductor material. Another aspect of the present invention is an organic semiconductor film characterized by being formed by dissolving the organic semiconductor material in an organic solvent, and applying and drying the prepared solution.

Another aspect of the present invention is an organic electronic device characterized by using the above organic semiconductor material. The above organic electronic device is preferably any one of a light emitting element, an organic thin film transistor, and a photo electromotive force (electromotive force) element, and more preferably an organic thin film transistor.

1 is a schematic cross-sectional view showing an example of an organic field effect transistor element.
2 is a schematic cross-sectional view showing an example of an organic field effect transistor element.
3 is a schematic cross-sectional view showing an example of an organic field effect transistor element.
4 is a schematic cross-sectional view showing an example of an organic field effect transistor element.
5 is a schematic cross-sectional view showing an example of the structure of a photovoltaic power device.
6 is a schematic sectional view showing an example of the structure of a photovoltaic power device.

The nitrogen-containing aromatic heterocyclic compound of the present invention is represented by the general formula (1).

In the general formula (1), R is independently hydrogen, an aliphatic hydrocarbon group of 1 to 30 carbon atoms, an aromatic group of 3 to 50 carbon atoms, an aromatic substituted alkyl group of 4 to 60 carbon atoms, an aromatic substituted alkenyl group of 5 to 60 carbon atoms, At least one of R is an aromatic group having 3 to 50 carbon atoms, an aromatic substituted alkyl group having 4 to 60 carbon atoms, an aromatic substituted alkenyl group having 5 to 60 carbon atoms, or an aromatic substituted alkenyl group having 5 to 60 carbon atoms An aromatic substituted alkynyl group. These groups may also have substituents and, when having one or more substituents, include the number of carbon atoms of such substituents in the calculation of the number of carbon atoms. Here, the aromatic group means an aromatic hydrocarbon group and an aromatic heterocyclic group, and the aromatic group may be an aromatic hydrocarbon group or an aromatic heterocyclic group.

R represents an aliphatic hydrocarbon group having 1 to 30 carbon atoms, an aromatic group having 3 to 50 carbon atoms, an aromatic substituted alkyl group having 4 to 60 carbon atoms, an aromatic substituted alkenyl group having 5 to 60 carbon atoms, or an aromatic substituted alkynyl group having 5 to 60 carbon atoms These groups of cases will be described.

The aliphatic hydrocarbon group is preferably an alkyl group having from 1 to 16 carbon atoms and specific examples thereof include a methyl group, ethyl group, n-propyl group, i-propyl group, n-butyl group, n-pentyl group, n- , a straight chain saturated hydrocarbon group such as n-dodecyl group, n-tetradecyl group, n-octadecyl group, n-tocodecyl group and n-tetracosyl group, isobutyl group, neopentyl group, Branched saturated hydrocarbon groups such as a hexyloctyl group and a 4-decyldodecyl group, saturated alicyclic hydrocarbons such as an alkyl group, a cyclopentyl group, a cyclohexyl group, a cyclooctyl group, a 4-butylcyclohexyl group, An unsaturated alicyclic hydrocarbon group such as a cyclopentenyl group, a cyclopentadienyl group, and a cyclohexenyl group.

The alkenyl group is preferably an alkenyl group having 2 to 10 carbon atoms, and specific examples thereof include a vinyl group, an allyl group, and a butenyl group.

The alkynyl group is preferably an alkynyl group having 2 to 10 carbon atoms, and specific examples thereof include an ethynyl group, a propynyl group, and a butynyl group.

The aromatic group is preferably an aromatic group having 3 to 36 carbon atoms, and specific examples thereof include benzene, pentalene, indene, naphthalene, azulene, heptalene, octalene, indacene, acenaphthylene, phenalene, phenanthrene, And examples thereof include aromatic hydrocarbons such as benzene, toluene, xylene, benzene, toluene, xylene, xylene, lanthanum, linden, fluoranthene, But are not limited to, pentacene, tetraphenylene, helicene, hexaphene, rubisene, coronene, trinaphthylene, heptapene, pyranthrene, ovalene, corannulene, fulminene, (S), anthanthrene, zethrene, terrylene, naphthacenonaphthacene, truxene, furan, benzofuran, isobenzofuran, xanthene, oxanthrene, dibenzofuran, Thiophene, thienothiophene, dithienothiophene, thioxanthene, thianthrene, phenothiine (phe noxathiin, thionaphthene, isothianaphthene, thioctene, thiopantrene, dibenzothiophene, pyrrole, pyrazole, tellurazole, selenazole, thiazole, isothiazole, oxa A furazan, a pyridine, pyrazine, pyrimidine, pyridazine, triazine, indolizine, indole, isoindole, indazole, purine, quinolizine, isoquinoline, carbazole, imidazole, Naphthyridine, phthalazine, quinazoline, benzodiazepine, quinoxaline, cinnoline, quinoline, pteridine, phenanthridine, acridine, perimidine, phenanthroline, phenazine Phenothiazine, phenoselenazine, phenothiazine, phenoxazone, antithyridine, thebenidine, quadrone, quinin doline, acridone, phthalopherin, Phenanthridine, phenanthraquinone, anthracene, benzothiazole, benzoimidazole, benzooxane, Benzoisooxazole, benzoisothiazole, indolocarbazole or a group formed by removing hydrogen from an aromatic compound having plural aromatic rings linked thereto. And more preferably from aromatic compounds having multiple aromatic rings linked thereto, such as benzene, naphthalene, phenanthrene, anthracene, chrysene, furan, thiophene, thienothiophene, dithienothiophene, pyrrole, carbazole, indolocarbazole, And the like. On the other hand, when the aromatic ring is a group derived from aromatic compounds having plural aromatic rings, the number of the aromatic rings to be connected is preferably 2 to 10, more preferably 2 to 7, and the connected aromatic rings may be the same or different.

In the case of a condensed ring, it is preferably a condensed ring condensed with 2 to 5 rings.

Here, the group in which a plurality of aromatic rings are connected is represented by the following formula, for example.

Here, Ar ¹ to Ar ⁶ represent a substituted or unsubstituted aromatic ring. Provided that in this case, the aromatic group which is branched and connected is not treated as a substituent.

Specific examples of groups in which a plurality of the aromatic rings are connected include, for example, biphenyl, terphenyl, bipyridine, bipyrimidine, phenylnaphthalene, diphenylnaphthalene, phenylphenanthrene, pyridylbenzene, pyridylphenanthrene, A group formed by excluding hydrogen from bithiophene, thothiophene, vithienothiophene, phenylindolocarbazole, and the like.

The aromatic substituted alkyl group is preferably an aromatic substituted alkyl group having 4 to 44 carbon atoms, and the aromatic substituted alkenyl group is preferably an aromatic substituted alkenyl group having 5 to 44 carbon atoms, and the aromatic substituted alkynyl group is preferably an aromatic substituted alkynyl group having 5 to 44 carbon atoms Do. The aromatic substitution group is interpreted as a group in which the aromatic group is substituted with the alkyl group, the alkenyl group and the alkynyl group.

The above alkyl group or aromatic group, aromatic substituted alkyl group, aromatic substituted alkenyl group or aromatic substituted alkynyl group may have a substituent. The substituent is not limited unless the performance of the semiconductor material is impaired. The total number of substituents is 1 to 4, Is 1 to 2. On the other hand, an aromatic ring derived from a plurality of aromatic rings may have a substituent as well. Preferred examples of the substituent include an alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, an alkylthio group having 1 to 20 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, an alkynyl group having 2 to 10 carbon atoms, An aromatic substituted alkenyl group having 5 to 60 carbon atoms, an alkoxycarbonyl group having 2 to 10 carbon atoms, an alkoxycarbonyloxy group having 2 to 10 carbon atoms, an alkylsulfonyl group having 1 to 10 carbon atoms, a halo having 1 to 10 carbon atoms An alkyl group having 2 to 10 carbon atoms, a trialkylsilyl group having 3 to 20 carbon atoms, a trialkylsilylalkyl group having 4 to 20 carbon atoms, a trialkylsilylalkenyl group having 5 to 20 carbon atoms, a trialkylsilyl An alkynyl group, and a trialkylsilylethynyl group having 5 to 20 carbon atoms. More preferably an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, an alkylthio group having 1 to 12 carbon atoms, an alkenyl group having 2 to 8 carbon atoms, an alkynyl group having 2 to 8 carbon atoms, An n-propyl group, an n-butyl group, an n-pentyl group, an n-hexyl group, a n-hexyl group, a n-hexyl group and a n-hexyl group. A straight chain saturated hydrocarbon group such as an octyl group, an n-dodecyl group, a n-tetradecyl group, an n-octadecyl group, an n-tocodecyl group and an n-tetracosyl group, an isobutyl group, a neopentyl group, Branched saturated hydrocarbon groups such as cyclopentyl group, cyclohexyl group, cyclooctyl group, 4-butylcyclohexyl group and 4-dodecylclohexyl group; branched saturated hydrocarbon groups such as acyl group, 2-hexyloctyl group and 4-decyldodecyl group; Propyl group, 2-propyl group, 2-propenyl group, 2-propenyl group, 2-propenyl group, Butynyl group, 3-butynyl group, ethynyl group, 1-propynyl group, 2-propynyl group, 1-butynyl group, 2-butynyl group, 2-butynyl group, A methoxycarbonyl group, an ethoxycarbonyl group, a methoxycarbonyloxy group, an ethoxycarbonyloxy group and the like. When two or more substituents are present, they may be the same or different.

In the general formula (1), n independently represents an integer of 1 to 4. However, at least one of R is a group selected from an aromatic group having 3 to 50 carbon atoms, an aromatic substituted alkyl group having 4 to 60 carbon atoms, an aromatic substituted alkenyl group having 5 to 60 carbon atoms, or an aromatic substituted alkynyl group having 5 to 60 carbon atoms. There may be 4n R, but a group other than H is preferably in the range of 1 to 4.

Among the compounds represented by the general formula (1), the compounds represented by the general formula (2) are preferred. In the general formula (2), R has the same meaning as R in the general formula (1). In the general formula (2), there are eight Rs, and among them, a group other than H is preferably in the range of 1 to 4.

The nitrogen-containing aromatic heterocyclic compound represented by the general formula (3) is useful as an intermediate of the compound represented by the general formula (1). In the general formula (3), X represents a halogen atom, a hydroxyl group, a boronic acid, a boronic acid ester, or a sulfonyl group. The nitrogen-containing aromatic heterocyclic compound represented by the general formula (3) is also a novel compound.

The nitrogen-containing aromatic heterocyclic compound represented by the general formula (1) can be prepared by reacting the nitrogen-containing aromatic heterocyclic compound represented by the general formula (3) with the compound represented by the general formula (4).

In the formula (4), R is the same as R in formula (1), and Y is a functional group which reacts with X to desorb.

The compounds represented by the general formula (1) of the present invention can be synthesized by the following reaction formulas (A), (B) and B), and (C). The compound represented by the general formula (3) is obtained as an intermediate thereof.

Namely, by carrying out a cyclization reaction and a substitution reaction as shown in Reaction Scheme (A), (B) or (C) by using indole having a desired substituent and 2-chlorobenzaldehyde as raw materials, Compound can be obtained. Alternatively, 2-bromobenzaldehyde or 2-iodobenzaldehyde may be used instead of 2-chlorobenzaldehyde.

Specific examples of the compound represented by the general formula (1) are shown below, but the compounds of the present invention are not limited thereto.

The organic semiconductor material of the present invention includes the compound of the general formula (1), but it preferably contains 50 wt% or more of the compound, more preferably 90 wt% or more. It is also preferable that the compound of the general formula (1) itself is an organic semiconductor material. The component contained in the organic semiconductor material together with the compound of the general formula (1) is not particularly limited as far as the performance as the organic semiconductor material is not impaired, but it is preferable that the organic semiconductor material is a charge transporting compound.

The organic semiconductor film of the present invention is formed of the organic semiconductor material. Advantageously, the organic semiconductor material is dissolved in an organic solvent, and the prepared solution is applied and dried. This organic semiconductor film is useful as an organic semiconductor layer in an organic electronic device.

Next, an organic electronic device including an organic semiconductor material which is formed by the organic semiconductor material of the present invention will be described with reference to Figs. 1 to 4, taking an organic thin film transistor element (OTFT element) as an example. The organic electronic device of the present invention is preferably an organic semiconductor device comprising an organic semiconductor material.

1, 2, 3, and 4 are schematic cross-sectional views illustrating the structure of an OTFT device according to an embodiment of the present invention.

The OTFT device shown in Fig. 1 has a gate electrode 2 on a surface of a substrate 1, an insulating film layer 3 on a gate electrode 2, and a source electrode 5 And a drain electrode 6 are formed, and an organic semiconductor layer 4 is formed.

The OTFT device shown in Fig. 2 has a gate electrode 2 on the surface of a substrate 1, an insulating film layer 3 on the gate electrode 2, and an organic semiconductor layer 4 on the gate electrode 2 A source electrode 5 and a drain electrode 6 are provided on the organic semiconductor layer 4.

The OTFT device shown in Fig. 3 has a structure in which a source electrode 5 and a drain electrode 6 are provided on the surface of a substrate 1, and a gate electrode (not shown) is formed on the outermost surface through the organic semiconductor layer 4 and the insulating film layer 3 2 are formed.

4, the organic semiconductor device according to the present invention is characterized in that the organic semiconductor layer 4, the source electrode 5 and the drain electrode 6 are provided on the surface of the substrate 1, 3, the gate electrode 2 is formed on the outermost surface.

Examples of the substrate used for the substrate 1 include ceramics substrates such as glass, quartz, aluminum oxide, sapphire, silicon nitride and silicon carbide; semiconductor substrates such as silicon, germanium, gallium arsenide, gallium phosphorus and gallium nitride; , Polyesters such as polynaphthalene terephthalate, and resin substrates such as polyethylene, polypropylene, polyvinyl alcohol, ethylene vinyl alcohol copolymer, cyclic polyolefin, polyimide, polyamide and polystyrene. The substrate may have a thickness of about 10 탆 to about 2 탆. In the case of a flexible plastic substrate, for example, about 50 to about 100 탆 may be used. For a rigid substrate such as a glass plate or a silicon wafer, About 2 mm.

The gate electrode 2 may be a metal thin film, a conductive polymer film, a conductive film made of a conductive ink or paste, or may be a gate electrode, for example, a substrate doped with moderate severity . Examples of the gate electrode material include aluminum, copper, stainless steel, gold, chromium, n-doped or p-doped silicon, indium tin oxide, conductive polymers such as poly (3,4- ), A conductive ink / paste containing carbon black / graphite, or a dispersion of colloidal silver in a polymer binder.

The gate electrode 2 may be formed by vacuum deposition, sputtering of metal or conductive metal oxide, spin coating of conductive polymer solution or conductive ink, inkjet, spraying, coating, casting or the like. The thickness of the gate electrode 2 is preferably in the range of, for example, about 10 nm to 10 mu m.

The insulating film layer 3 can be generally formed of an inorganic material film or an organic polymer film. Examples of the inorganic material preferable as the insulating film layer 3 include silicon oxide, silicon nitride, aluminum oxide, barium titanate, and barium zirconium titanate. Examples of the organic compound that is preferable as the insulating film layer 3 include polyesters, polycarbonates, poly (vinylphenol), polyimides, polystyrene, poly (methacrylate) . An inorganic material may be dispersed in the organic polymer and used as an insulating layer film. The thickness of the insulating film layer depends on the dielectric constant of the insulating material to be used, and is, for example, about 10 nm to 10 탆.

Examples of the means for forming the insulating film layer include a dry film forming method such as a vacuum evaporation method, a CVD method, a sputtering method and a laser deposition method, a wet film forming method such as a spin coating method, a blade coating method, a screen printing method, A film forming method can be used, and it can be used depending on the material.

The source electrode 5 and the drain electrode 6 may be made of a material which gives a low resistance ohmic contact to the organic semiconductor layer 4 to be described later. As a preferable material for the source electrode 5 and the drain electrode 6, those exemplified as preferable materials for the gate electrode 2 can be used. For example, gold, nickel, aluminum, platinum, a conductive polymer and a conductive ink . The thickness of the source electrode 5 and the drain electrode 6 is typically about 40 nm to about 10 mu m, and more preferably about 10 nm to 1 mu m in thickness.

Examples of means for forming the source electrode 5 and the drain electrode 6 include a vacuum deposition method, a spattering method, a coating method, a thermal transfer method, a printing method, and a sol-gel method. At the time of film formation or after film formation, it is preferable to perform patterning as required. As the patterning method, for example, a photolithography method in which patterning and etching of a photoresist are combined, and the like can be given. It is also possible to perform patterning using a combination of a plurality of these techniques such as inkjet printing, screen printing, offset printing, and soft lithography such as micro contact printing.

Examples of the means for forming the organic semiconductor layer 4 include a dry film forming method such as a vacuum vapor deposition method, a CVD method, a sputtering method and a laser vapor deposition method, or a method in which a solvent or a dispersion medium is removed after applying a solution or dispersion onto a substrate A wet film-forming method in which a thin film is formed, and it is preferable to use a wet film-forming method. Examples of the wet film forming method include a spin coating method, a blade coating method, a screen printing method, an inkjet printing method, a stamping method, and the like. For example, when spin coating is used, the organic semiconductor material of the present invention is dissolved in a suitable solvent having solubility to prepare a solution having a concentration of 0.01 wt% to 10 wt%, and then the insulating film layer 3 ), And then rotating the organic semiconductor material solution for 5 to 120 seconds at 500 to 6000 rpm. The solvent is selected depending on the solubility of the organic semiconductor material in each solvent and the film quality after film formation. Examples of the solvent include alcohols such as water and methanol, aromatic hydrocarbons such as toluene, and aromatic hydrocarbons such as hexane and cyclohexane , Organic nitric compounds such as nitromethane and nitrobenzene, cyclic ether compounds such as tetrahydrofuran and dioxane, nitrile compounds such as acetonitrile and benzonitrile, ketones such as acetone and methyl ethyl ketone , Ethyl acetate and the like, and aprotic polar solvents such as dimethylsulfoxide, dimethylacetamide, sulfolane, N-methylpyrrolidone, dimethylimidazolidinone, etc. . These solvents may be used in combination of two or more kinds.

With the above-described method, an organic field effect transistor device using the organic semiconductor material of the present invention can be produced. In the obtained organic field effect transistor device, the organic semiconductor layer forms a channel region, and the current flowing between the source electrode and the drain electrode is controlled by a voltage applied to the gate electrode, thereby performing on / off operation.

One of the other suitable embodiments of the organic semiconductor device obtained from the organic semiconductor material of the present invention is a photovoltaic device. Specifically, the present invention is an organic electroluminescent device having an anode, an organic semiconductor layer, and a cathode on a substrate, wherein the organic semiconductor layer includes the organic semiconductor material of the present invention described above.

The structure of the opto-electromotive force element of the present invention will be described with reference to the drawings, but the structure of the opto-electromotive force element of the present invention is not limited to what is shown.

5 is a cross-sectional view showing an example of the structure of a general photovoltaic device used in the present invention, in which 7 is a substrate, 8 is an anode, 9 is an organic semiconductor layer, and 10 is a cathode. 6 is a cross-sectional view showing an example of the structure in which the organic semiconductor layers are laminated. 9-a is a p-type organic semiconductor layer and 9-b is an n-type organic semiconductor layer.

The substrate is not particularly limited, and for example, a conventionally known structure can be used. It is preferable to use a glass substrate or a transparent resin film having mechanical and thermal strength and transparency. Examples of the transparent resin film include polyethylene, ethylene-vinyl acetate copolymer, ethylene-vinyl alcohol copolymer, polypropylene, polystyrene, polymethylmethacrylate, polyvinyl chloride, polyvinyl alcohol, polyvinyl butyral, nylon, polyether ether Ketone, polysulfone, polyethersulfone, tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer, polyvinyl fluoride, tetrafluoroethylene-ethylene copolymer, tetrafluoroethylene-hexafluoropropylene copolymer, polychloro Polytetrafluoroethylene, trifluoroethylene, polyvinylidene fluoride, polyester, polycarbonate, polyurethane, polyimide, polyetherimide, polyimide, polypropylene and the like.

As the electrode material, it is preferable to use a conductive material having a large work function for one electrode and a conductive material having a small work function for the other electrode. An electrode using a conductive material having a large work function becomes an anode. In addition to metals such as gold, platinum, chromium and nickel, metal oxides such as indium and tin, complex metal oxides (indium tin oxide (ITO), indium zinc oxide (IZO), etc.) ) Is preferably used. Here, it is preferable that the conductive material used for the anode is ohmic-bonded to the organic semiconductor layer. In the case of using a hole transporting layer described below, it is preferable that the conductive material used for the anode is ohmic-bonded to the hole transporting layer.

An electrode using a conductive material having a small work function becomes a negative electrode. As the conductive material having a small work function, an alkali metal or an alkaline earth metal, specifically, lithium, magnesium or calcium is used. Also, tin, silver and aluminum are preferably used. An electrode made of the metal or a laminate of the metal is also preferably used. It is also possible to improve the extraction current by introducing a metal fluoride such as lithium fluoride or cesium fluoride to the interface between the cathode and the electron transport layer. Here, the conductive material used for the cathode preferably is an ohmic contact with the organic semiconductor layer. In the case of using an electron transporting layer to be described later, it is preferable that the conductive material used for the cathode is an ohmic contact with the electron transporting layer.

- Organic semiconductor layer -

The organic semiconductor layer includes the compound of the present invention. That is, it is formed using the organic semiconductor material of the present invention including the compound represented by the formula (1). The organic semiconductor material of the present invention is used for a p-type organic semiconductor material (hereinafter referred to as a p-type organic material), an n-type organic semiconductor material (hereinafter referred to as an n-type organic material) At least one of the compounds represented by the formula (1) may be used as a p-type organic material component and at least one other may be used as an n-type organic material component. In addition, one of the p-type organic material or the n-type organic material may be a compound not containing the compound represented by the formula (1).

The organic semiconductor layer is formed using an organic semiconductor material containing at least one compound represented by the formula (1). The compound represented by the formula (1) functions as a p-type organic material or an n-type organic material.

It is preferable that the p-type organic material and the n-type organic material are mixed with each other, and the p-type organic material and the n-type organic material are preferably used at the molecular level or phase-separated. The domain size of the phase separation structure is not particularly limited, but is usually 1 nm or more and 50 nm or less in size. When the p-type organic material and the n-type organic material are stacked, the layer having the p-type organic material exhibiting the p-type semiconductor characteristic is on the anode side, and the layer having the n-type organic material exhibiting the n- . The thickness of the organic semiconductor layer is preferably 5 nm to 500 nm, more preferably 30 nm to 300 nm. When stacked, the layer having a p-type organic material of the present invention preferably has a thickness of 1 nm to 400 nm, more preferably 15 nm to 150 nm, of the above thickness.

Among the compounds represented by the formula (1), the p-type organic material may be used singly or in combination with other p-type organic materials. Examples of other p-type organic materials include polythiophene polymers, benzothiadiazole-thiophene derivatives, benzothiadiazole-thiophene copolymers, poly-p-phenylene vinylene- (H2Pc), copper phthalocyanine (CuPc), copper phthalocyanine (CuPc), and copper phthalocyanine (Pb), or a conjugated polymer such as a p-phenylene type polymer, a polyfluorene type polymer, a polypyrrole type polymer, a polyaniline type polymer, a polyacetylene type polymer and a polythienylene vinylene type polymer. N, N'-di (3-methylphenyl) -4,4'-diphenyl-1,1'-diamine (TPD), zinc phthalocyanine , Triarylamine derivatives such as N, N'-dinaphthyl-N, N'-diphenyl-4,4'-diphenyl-1,1'-diamine (NPD) Carbazol derivatives such as benzothiophene-9-yl) biphenyl (CBP), and low molecular weight compounds such as oligothiophen derivatives (terthiophene, quaterthiophene, sexithiophene, octithiophene etc.) Based compounds.

Among the compounds represented by the formula (1), the n-type organic material may be used singly or in combination with other n-type organic materials. Other n-type organic materials include, for example, 1,4,5,8-naphthalene tetracarboxylic dianhydride (NTCDA), 3,4,9,10-perylene tetracarboxylic dianhydride (PTCDA ), 3,4,9,10-perylene tetracarboxylic bisbenzimidazole (PTCBI), N, N'-dioctyl-3,4,9,10-naphthyltetracarboxydimide (PTCDI-C8H ), 2- (4-biphenylyl) -5- (4-t-butylphenyl) -1,3,4-oxadiazole (PBD) An oxazole derivative such as 3,4-oxadiazole (BND), an oxazole derivative such as 3- (4-biphenyl) -4-phenyl-5- (4-t-butylphenyl) (6,6] -Phenyl C61 (C60, C70, C76, C78, C82, C84, C90, C94 and the like) and a triazine derivative such as a triazine derivative such as a phenanthroline derivative, a phosphine oxide derivative, Phenyl] C61 butyric acid methyl ester ([6,6] -PCBM), [6,6] -phenyl C61 butyric acid hexyl ester ([6,6] ] -PCBH), [6,6] -phenyl C61 butyrate dodecyl ester ([6,6] (CNT), a derivative in which a cyano group is introduced into a poly-p-phenylenevinylene-based polymer (CN-COOH), a C7 butyric acid methyl ester (PC70BM), a phenyl C85 butyric acid methyl ester PPV).

In the photo-electromotive force device of the present invention, a hole transporting layer may be provided between the anode and the organic semiconductor layer. Examples of the material for forming the hole transport layer include conductive polymers such as polythiophene type polymers, poly-p-phenylenevinylene type polymers and polyfluorene type polymers, phthalocyanine derivatives (H2Pc, CuPc, ZnPc and the like) A low-molecular organic compound exhibiting a p-type semiconductor property is preferably used. In particular, polythiophene-based polymers such as polyethylene dioxythiophene (PEDOT) and PEDOT to which polystyrene sulfonate (PSS) is added are preferably used. The thickness of the hole transporting layer is preferably from 5 nm to 600 nm, more preferably from 30 nm to 200 nm.

In the photo-electromotive force device of the present invention, an electron transporting layer may be provided between the organic semiconductor layer and the cathode. The material for forming the electron transporting layer is not particularly limited. The n-type organic material (NTCDA, PTCDA, PTCDI-C8H, oxazole derivative, triazole derivative, phenanthroline derivative, phosphine oxide derivative, fullerene compound, CNT , CN-PPV, and the like), an organic material exhibiting n-type semiconductor characteristics is preferably used. The thickness of the electron transporting layer is preferably 5 nm to 600 nm, more preferably 30 nm to 200 nm.

In the photo-electromotive force element of the present invention, two or more organic semiconductor layers may be laminated (tandemized) through one or more intermediate electrodes to form a series junction. For example, a stacked structure of substrate / anode / first organic semiconductor layer / intermediate electrode / second organic semiconductor layer / cathode. By stacking in this way, the open-circuit voltage can be improved. On the other hand, the above-described hole transporting layer may be provided between the anode and the first organic semiconductor layer and between the intermediate electrode and the second organic semiconductor layer, and between the first organic semiconductor layer and the intermediate electrode, The above-described hole transporting layer may be provided between the anode and the cathode.

In the case of such a laminated structure, at least one layer of the organic semiconductor layer contains the compound of the present invention represented by the formula (1), and in order not to lower the short-circuit current in the other layer, It is preferable to include other p-type organic materials. Examples of the p-type organic material include a polythiophene-based polymer, a poly-p-phenylenevinylene-based polymer, a poly-p-phenylene-based polymer, a polyfluorene-based polymer, a polypyrrole- , Polyacetylene-based polymers and polythienylene-vinylene-based polymers, phthalocyanine derivatives such as H2 phthalocyanine (H2Pc), copper phthalocyanine (CuPc) and zinc phthalocyanine (ZnPc), porphyrin derivatives, N, Phenyl-N, N'-di (3-methylphenyl) -4,4'-diphenyl-1,1'-diamine (TPD), N, N'-dinaphthyl- , Triarylamine derivatives such as 4'-diphenyl-1,1'-diamine (NPD), carbazole derivatives such as 4,4'-di (carbazol-9-yl) biphenyl (CBP) And low-molecular organic compounds such as an opene derivative (terthiophene, quaterthiophene, sexy thiophene, octthiophene, etc.).

As the material for the intermediate electrode used herein, it is preferable to have a high conductivity, and for example, a metal such as gold, platinum, chromium, nickel, lithium, magnesium, calcium, tin, (Indium tin oxide (ITO), indium zinc oxide (IZO), etc.), an alloy of the above metals, a laminate of the above metals, a polyethylene dioxythiophene (PEDOT ) Or polystyrene sulfonate (PSS) added to PEDOT. Although the intermediate electrode preferably has light transmittance, it is often the case that even a material such as a metal having low light transmittance can secure sufficient light transmittance by making the film thickness thin.

The formation of the organic semiconductor layer may be carried out by a spin coating method, a blade coating method, a slit die coating method, a screen printing application method, a bar coater application method, a mold type application method, a printing transfer method, Method, a vacuum evaporation method, or the like may be used. The formation method may be selected according to the properties of the organic semiconductor layer to be obtained, such as film thickness control and orientation control.

The organic semiconductor device of the present invention uses the organic semiconductor material of the present invention. Such an organic semiconductor device includes a light emitting element, a thin film transistor, or a photovoltaic power element, preferably a thin film transistor or a photovoltaic power element, more preferably an organic thin film transistor.

The organic semiconductor material of the present invention has high mobility, solvent solubility, oxidation stability, and good film forming property, and organic semiconductor devices using the organic semiconductor material exhibit high characteristics. Specific organic semiconductor devices capable of taking advantage of the characteristics of the organic semiconductor material of the present invention include, for example, organic field effect transistors and organic thin film solar cells. By including these organic semiconductor devices, A large area sensor such as a sheet or sheet type scanner, a liquid crystal display, an electronic paper, and an organic EL panel.

Example

Hereinafter, the present invention will be described in more detail by way of examples, but the present invention is of course not limited to these embodiments, and can be carried out in various forms without departing from the gist of the present invention. On the other hand, the compound number corresponds to the number attached to the above formula.

Synthesis Example 1

Synthesis of Compound (100)

5-bromoindole (25 g, 130 mmol), 2-bromobenzaldehyde (9.2 g, 65 mmol) and methanol (180 ml) were added to a 300 ml three-necked flask equipped with a reflux condenser, And stirred for 22 hours. After cooling to room temperature, the solvent was removed by distillation. The residue was purified by silica gel column chromatography, and the obtained solid was dried in vacuo (50 DEG C) overnight to obtain a red solid (A-1, 29.4 g, yield 81%).

Intermediate (A-1) (29 g, 51.9 mmol), iodine (5.3 g, 2.1 mmol) and acetonitrile (87 ml) were added to a 200 ml three-necked flask equipped with a reflux tube, . After cooling to room temperature, the mixture was filtered. Thereafter, the slurry was subjected to acetonitrile slurry, and then dried overnight at 50 ° C to obtain a white solid (A-2, 4.0 g, yield: 11%).

In a 200 ml three-necked flask equipped with a reflux tube, dehydrated DMF (110 ml), 38% tetrabutylammonium hydroxide methanol solution (8.9 g, 12.7 mmol) and intermediate (A-2) 5.52 mmol), which was stirred for 48 hours at 120 deg. After cooling to room temperature, the mixture was filtered. Thereafter, a methanol-heated slurry and THF / MeOH crystallization were carried out to obtain a greenish yellow compound (A-3, 0.8 g).

(A-3, 1.0 g, 1.78 mmol), phenylboronic acid (441 mg, 3.56 mmol, 2.0 eq.), Tetrakis (triphenylphosphine) palladium (103 mg, 0.089 mmol, 0.05 eq.), Toluene (7.0 ml) and ethanol (3.0 ml) were added thereto, followed by stirring at room temperature. 2.5M aqueous sodium carbonate solution (985 mg, 9.29 mmol / H ₂ O 3.72 ml) was added, and the mixture was stirred at 90 ° C for 14 hours. After the reaction solution was cooled to room temperature, the organic layer was washed with water, dried over anhydrous magnesium sulfate, filtered, and the filtrate was concentrated. The resulting yellowish green solid (1.0 g) was dissolved in THF (25 g) and methanol (125 g) was poured with stirring at room temperature (0.73 g recovery). Thereafter, the mixture was stirred at room temperature for 2 hours to precipitate the precipitate by filtration. This operation was repeated four times to obtain 0.28 g of a solid. Thereafter, a solid, THF (7 g) and activated carbon (0.07 g) were added to a 25 ml Nasflask, stirred at room temperature for 30 minutes, and filtered. The filtrate was concentrated and dried to obtain 0.1 g of compound (100) as a yellowish green solid. FDMS, m / z 556

Example 1

A compound (100) synthesized in Synthesis Example 1 was vapor-deposited on an ITO substrate having a film thickness of 150 nm by vapor deposition to form an organic semiconductor film having a thickness of about 2.5 mm. Then, silver was vapor- I made it. The obtained device was evaluated for charge mobility by the TOF method. As a result, the hole mobility was 3.9 × 10 ^-2 cm ² / Vs at an electric field intensity of 51.0 MV / cm.

Example 2

The characteristics of the organic semiconductor material of the present invention were evaluated by preparing and evaluating the organic field effect transistor having the structure shown in Fig. First, a silicon wafer (n-dope) having a thermally grown silicon oxide layer having a thickness of about 300 nm was washed with an aqueous sulfuric acid-hydrogen peroxide solution, boiled with isopropyl alcohol and dried. The obtained silicon wafer was spin-coated with a photoresist, and then exposed through a photomask using an exposure machine. Next, development was carried out with a developing solution, followed by washing with ion-exchanged water and air drying. On the silicon wafer coated with the patterned photoresist, 3 nm thick chromium and 50 nm gold were deposited thereon by a vacuum deposition method. The silicon wafer was immersed in a remover solution to prepare a source electrode and a drain electrode on a silicon wafer. A silicon wafer on which a source electrode and a drain electrode were formed was cleaned with acetone and further boiled with isopropyl alcohol to dryness, thereby preparing an organic field effect transistor substrate. The channel length was L = 25 mu m, and the channel width was W = 15.6 cm.

Next, the compound (100) obtained in Example 1 was vapor-deposited by vacuum evaporation to form an organic semiconductor film having a film thickness of 50 nm on the substrate. Thus, an organic field effect transistor having the structure shown in Fig. 1 was obtained. As a result of evaluating the characteristics of the obtained organic field effect transistor, mobility; 4.0 × 10 ^-1 cm ² / Vs.

Comparative Example 1

An organic field effect transistor device was fabricated in the same manner as in Example 2, except that pentacene was used instead of the compound (100). The obtained device was evaluated in the same manner as in Example 2, and as a result, mobility was measured. 1.0 × 10 ^-1 cm ² / Vs.

As described above, by comparing Example 2 and Comparative Example 1, it became clear that the structure represented by Formula (1) has high characteristics as an organic semiconductor.

Since the nitrogen-containing aromatic heterocyclic compound of the present invention has a conjugated structure spread throughout the molecular structure, its electron orbit is also distributed throughout the molecular structure. Further, since the three-dimensional structure has a high planarity, the packing between the molecules becomes dense, and as a result, the nitrogen-containing aromatic heterocyclic compound of the present invention exhibits high charge transfer characteristics. Accordingly, the organic electronic device of the present invention is capable of exhibiting high characteristics and can be applied to a large-area sensor such as an organic field effect transistor, an organic thin film solar cell, an information tag, an electronic artificial skin sheet or a sheet type scanner, An electronic paper, and an organic EL panel, and the like, and thus its technical value is large.

1 substrate, 2 gate electrode, 3 insulating layer, 4 organic semiconductor, 5 source electrode, 6 drain electrode, 7 substrate, 8 anode, 9 organic semiconductor layer, 9-a electron donating organic semiconductor layer, 9 -b electron-accepting organic semiconductor layer, 10 cathode.

Claims (11)

A nitrogen-containing aromatic heterocyclic compound represented by the following general formula (1).

In formula (1), each R independently represents hydrogen, an aliphatic hydrocarbon group of 1 to 30 carbon atoms, an aromatic hydrocarbon group of 6 to 50 carbon atoms, an aromatic heterocyclic group of 2 to 50 carbon atoms, an aromatic hydrocarbon- An aromatic hydrocarbon-substituted alkenyl group having 8 to 60 carbon atoms, an aromatic heterocyclic-substituted alkenyl group having 4 to 60 carbon atoms, an aromatic hydrocarbon-substituted alkynyl group having 8 to 60 carbon atoms, or an aromatic hydrocarbon-substituted alkenyl group having 4 to 60 carbon atoms An aromatic heterocyclic substituted alkynyl group,
At least one of R is an aromatic hydrocarbon group having 6 to 50 carbon atoms, an aromatic heterocyclic group having 2 to 50 carbon atoms, an aromatic hydrocarbon-substituted alkyl group having 7 to 60 carbon atoms, an aromatic heterocyclic substituted alkyl group having 3 to 60 carbon atoms, An aromatic hydrocarbon-substituted alkenyl group, an aromatic heterocyclic-substituted alkenyl group having 4 to 60 carbon atoms, an aromatic hydrocarbon-substituted alkynyl group having 8 to 60 carbon atoms, or an aromatic heterocyclic-substituted alkynyl group having 4 to 60 carbon atoms. n represents an integer of 1 to 4; The method according to claim 1,
A nitrogen-containing aromatic heterocyclic compound characterized by comprising a compound represented by the following general formula (2).

Wherein R is the same as R in the general formula (1) described in claim 1. A nitrogen-containing aromatic heterocyclic compound represented by the following general formula (3).

Wherein X represents a halogen atom, a hydroxyl group, a boronic acid, a boronic acid ester, or a sulfonyl group. n is the same as n in the general formula (1) described in claim 1. A nitrogen-containing aromatic heterocyclic compound represented by the following general formula (1), which is characterized by reacting a nitrogen-containing aromatic heterocyclic compound represented by the following general formula (3) with a compound represented by the following general formula (4) Gt;

In formula (1), each R independently represents hydrogen, an aliphatic hydrocarbon group of 1 to 30 carbon atoms, an aromatic hydrocarbon group of 6 to 50 carbon atoms, an aromatic heterocyclic group of 2 to 50 carbon atoms, an aromatic hydrocarbon- An aromatic hydrocarbon-substituted alkenyl group having 8 to 60 carbon atoms, an aromatic heterocyclic-substituted alkenyl group having 4 to 60 carbon atoms, an aromatic hydrocarbon-substituted alkynyl group having 8 to 60 carbon atoms, or an aromatic hydrocarbon-substituted alkenyl group having 4 to 60 carbon atoms An aromatic heterocyclic substituted alkynyl group,
At least one of R is an aromatic hydrocarbon group having 6 to 50 carbon atoms, an aromatic heterocyclic group having 2 to 50 carbon atoms, an aromatic hydrocarbon-substituted alkyl group having 7 to 60 carbon atoms, an aromatic heterocyclic substituted alkyl group having 3 to 60 carbon atoms, An aromatic hydrocarbon-substituted alkenyl group, an aromatic heterocyclic-substituted alkenyl group having 4 to 60 carbon atoms, an aromatic hydrocarbon-substituted alkynyl group having 8 to 60 carbon atoms, or an aromatic heterocyclic-substituted alkynyl group having 4 to 60 carbon atoms. n represents an integer of 1 to 4;
In the formula (3), X represents a halogen atom, a hydroxyl group, a boronic acid, a boronic acid ester, or a sulfonyl group. n has the same meaning as n in the general formula (1).
In the formula (4), R is the same as R in the formula (1), and Y is a functional group which reacts with X to desorb. An organic semiconductor material characterized by containing the nitrogen-containing aromatic heterocyclic compound according to claim 1. An organic semiconductor film formed of the organic semiconductor material according to claim 5. An organic semiconductor film formed by dissolving the organic semiconductor material according to claim 5 in an organic solvent, and applying and drying the prepared solution. An organic electronic device characterized by using the organic semiconductor material according to claim 5. 9. The method of claim 8,
Wherein the organic electronic device is one of a light emitting element, a thin film transistor, or a photo electromotive force (electromotive force) element. 9. The method of claim 8,
An organic electronic device, characterized in that the organic electronic device is one of a thin film transistor or a photovoltaic power device 9. The method of claim 8,
Wherein the organic electronic device is an organic thin film transistor.

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