JP2007087847A - Manufacturing method of organic semiconductor element, organic semiconductor element, organic semiconductor device and electronic equipment - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a manufacturing method of an organic semiconductor element, which manufactures the organic semiconductor element having superior characteristics, an organic semiconductor element manufactured by such manufacturing method of the organic semiconductor element, and also to provide an organic semiconductor device and an electronic equipment, each having this organic semiconductor element, with high reliability. <P>SOLUTION: The organic EL element (organic semiconductor element) 1 comprises: a positive electrode 3, a hole transporting layer 5; a luminous layer 6; and a negative electrode 8. The hole transporting layer (first organic semiconductor layer) 5 and the luminous layer (second organic semiconductor layer) 6 are obtained by applying processes of: preparing a first liquid material containing a first organic semiconductor material and a second liquid material containing a second organic semiconductor material; forming the first liquid material is supplied to the positive electrode 3 and a first liquid film; supplying a second liquid material on top of the first liquid film and forming a second liquid film; and solidifying the first liquid film and the second liquid film and forming the hole transporting layer and the luminous layer in one lot. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a method for manufacturing an organic semiconductor element, an organic semiconductor element, an organic semiconductor device, and an electronic apparatus.

Examples of the organic semiconductor element including a plurality of organic semiconductor layers include an organic electroluminescence element (hereinafter simply referred to as “organic EL element”), an organic thin film transistor, and the like.
Among these, the organic EL element is considered to be promising for use as an inexpensive large-area full-color display element (semiconductor element) of a solid light emitting type, and many developments have been made.

In general, an organic EL device has a light emitting layer between a cathode and an anode. When an electric field is applied between the cathode and the anode, electrons are injected into the light emitting layer from the cathode side, and holes are formed from the anode side. Is injected.
Then, the injected electrons and holes are recombined in the light emitting layer, and the light emitting layer emits light by releasing the excitation energy when the energy level returns from the conduction band to the valence band as light energy.

In such an organic EL element, in order to increase the efficiency of the organic EL element, that is, to obtain high light emission, an organic semiconductor layer composed of organic semiconductor materials having different electron or hole carrier transport properties is used as a light emitting layer. It has been found that an element structure laminated between the cathode and / or the anode is effective.
Therefore, it is necessary to laminate a light emitting layer and an organic semiconductor layer having different carrier transport properties (hereinafter collectively referred to as “organic semiconductor layer”) on the electrode. In the manufacturing method using the conventional coating method, When laminating organic semiconductor layers, phase dissolution occurs between adjacent organic semiconductor layers, and the carrier transport ability of these organic semiconductor layers is reduced. There has been a problem that characteristics such as color purity or pattern accuracy are deteriorated.

Therefore, in the case of stacking organic semiconductor layers, the organic semiconductor material is limited to stacking by using a combination of organic semiconductor materials having different solubility.
As a method for solving such a problem, a method of improving durability of the lower layer, that is, solvent resistance by polymerizing organic semiconductor materials constituting the lower organic semiconductor layer is disclosed (for example, , See Patent Document 1).

Also disclosed is a method for improving the solvent resistance of the lower layer by adding a curable resin to the organic semiconductor material constituting the lower organic semiconductor layer and curing it together with the curable resin (for example, , See Patent Document 2).
However, even when these methods are used, the actual situation is that the improvement of the characteristics of the organic EL element has not been obtained as expected.
Such a problem similarly occurs in organic thin film transistors and the like.

Japanese Patent Laid-Open No. 9-255774 JP 2002-151269 A

  An object of the present invention is to provide an organic semiconductor element manufacturing method capable of manufacturing an organic semiconductor element exhibiting excellent characteristics, an organic semiconductor element manufactured by such an organic semiconductor element manufacturing method, the organic semiconductor element including the organic semiconductor element, and reliability It is to provide a highly reliable organic semiconductor device and a highly reliable electronic device.

Such an object is achieved by the present invention described below.
The method for producing an organic semiconductor element of the present invention includes a first organic semiconductor layer mainly composed of a first organic semiconductor material and a second organic semiconductor mainly composed of a second organic semiconductor material on a substrate. An organic semiconductor element manufacturing method for manufacturing an organic semiconductor element formed by laminating layers in this order,
Dissolving the second organic semiconductor material in a first liquid material in which the first organic semiconductor material is dissolved or dispersed in the first liquid and a second liquid that is substantially incompatible with the first liquid. Or a first step of preparing a dispersed second liquid material;
A second step of supplying a first liquid material on the substrate to form a first liquid film;
A third step of forming the second liquid film by supplying the second liquid material on the first liquid film in a state where the first liquid film does not solidify;
By removing the first liquid and the second liquid from the first liquid film and the second liquid film, these films are solidified so that the first organic semiconductor layer and the second liquid are solidified. And a fourth step of collectively forming the organic semiconductor layer.
Thereby, phase dissolution is prevented from occurring between the first organic semiconductor layer and the second organic semiconductor layer, and a uniform interface is formed. Therefore, carriers between these layers are formed. Can be delivered smoothly. As a result, an organic semiconductor element provided with these layers exhibits excellent characteristics.

In the method for manufacturing an organic semiconductor element of the present invention, in the third step, the second liquid material is preferably supplied as droplets onto the first liquid film.
As a result, the second liquid material can be selectively supplied into the target region, so that waste of the second liquid material can be omitted.
In the method for manufacturing an organic semiconductor element of the present invention, in the fourth step, the first liquid and the second liquid are removed by bringing a flat plate into contact with the second film, and then the second liquid. It is preferable that the separation be performed in a state in which the distance between the flat plate and the substrate is defined so that the coating film is layered.
As a result, the second liquid film and the first liquid film are formed because the second liquid and the first liquid are removed in a state where the thickness thereof is substantially uniform. The film thicknesses of the second organic semiconductor layer and the first organic semiconductor layer can also be made substantially uniform.

In the method for producing an organic semiconductor element of the present invention, it is preferable that the flat plate has liquid repellency on a surface with which the second liquid material is brought into contact.
Thereby, in this process, after forming the 1st organic semiconductor layer and the 2nd organic semiconductor layer collectively, a flat plate can be easily removed from the 2nd organic semiconductor layer.
In the method for manufacturing an organic semiconductor element of the present invention, in the fourth step, the first liquid and the second liquid are used to heat and / or depressurize the first liquid material and the second liquid material. It is preferable that it is removed by doing.
Accordingly, the first organic semiconductor material is preferably prevented or suppressed from unintentionally diffusing to the second liquid film side and the second organic semiconductor material to the first liquid material side. The liquid film and the second liquid film can be quickly solidified.

In the method for manufacturing an organic semiconductor element of the present invention, the heating is preferably performed from the second liquid film side.
Thereby, since the removal of the second liquid is performed slightly earlier than the removal of the first liquid, the first organic semiconductor layer is formed after the second organic semiconductor layer is formed. . As a result, it is possible to more reliably prevent the first organic semiconductor material from diffusing to the second organic semiconductor layer side.

In the method for producing an organic semiconductor element of the present invention, it is preferable that the first liquid is a polar solvent, and the second liquid is a solvent having a polarity lower than that of the polar solvent.
Thereby, it can prevent or suppress that a 1st liquid and a 2nd liquid are compatible.
In the method for manufacturing an organic semiconductor element of the present invention, it is preferable that the first liquid material contains a dispersant that improves dispersibility of the first organic semiconductor material in the first liquid.
Thereby, since the micelle obtained by surrounding the first organic semiconductor material with the dispersant is formed in the first liquid, the first organic semiconductor material is reliably dispersed in the first liquid. Can do.

In the method for manufacturing an organic semiconductor element of the present invention, a mixing ratio of the first organic semiconductor material and the dispersant in the first liquid material is 10: 1 to 50: 1 by weight. preferable.
Thereby, since the micelle of a more appropriate size is formed in the first liquid, the first organic semiconductor material can be more reliably dispersed in the first liquid.

In the method for producing an organic semiconductor element of the present invention, when the boiling point of the first liquid is A [° C.] and the boiling point of the second liquid is B [° C.], the absolute value of AB is 75 or less. It is preferable to satisfy the following relationship.
Accordingly, the first organic semiconductor material and the second organic semiconductor material are accurately prevented or suppressed from being mixed in the vicinity of the interface between the first organic semiconductor layer and the second organic semiconductor layer to be formed. Can do.

In the method for producing an organic semiconductor element of the present invention, it is preferable that the first organic semiconductor material and the second organic semiconductor material are different.
Thereby, the interface of the dissimilar layer (a 1st organic-semiconductor layer and a 2nd organic-semiconductor layer) formed can be made uniform.
In the method for producing an organic semiconductor element of the present invention, the organic semiconductor element is an organic electroluminescence element,
It is preferable that the first organic semiconductor layer is a hole transport layer and the second organic semiconductor layer is a light emitting layer.
Thereby, since the interface between the formed hole transport layer and the light emitting layer becomes uniform, it is possible to smoothly transfer holes between these layers. As a result, the organic electroluminescence device including these layers has excellent characteristics such as luminous efficiency.

The organic semiconductor element of the present invention is manufactured by the method for manufacturing an organic semiconductor element of the present invention.
Thereby, an organic semiconductor element having excellent characteristics can be obtained.
The organic semiconductor device of the present invention includes the organic semiconductor element of the present invention.
Thereby, an organic semiconductor device with high reliability is obtained.
An electronic apparatus according to the present invention includes the organic semiconductor device according to the present invention.
Thereby, a highly reliable electronic device can be obtained.

Hereinafter, a method for manufacturing an organic semiconductor element, an organic semiconductor element, an organic semiconductor device, and an electronic apparatus according to the present invention will be described in detail with reference to the accompanying drawings.
First, an example of an active matrix display device to which the organic semiconductor device of the present invention is applied will be described.
<Active matrix display device>
FIG. 1 is a longitudinal sectional view showing an example of an active matrix display device to which an organic semiconductor device of the present invention is applied. FIGS. 2 to 3 are diagrams for explaining a method of manufacturing the active matrix display device shown in FIG. FIG. 2 is a longitudinal sectional view, and FIG. 3 is a schematic diagram. In the following description, the upper side in FIGS. 1 to 3 is referred to as “upper” and the lower side is referred to as “lower”.

An active matrix display device (hereinafter simply referred to as “display device”) 10 shown in FIG. 1 includes a TFT circuit substrate (counter substrate) 20 and an organic EL element (organic semiconductor element) provided on the substrate 20. 1 and an upper substrate 9 facing the TFT circuit substrate 20.
The TFT circuit substrate 20 includes a substrate 21 and a circuit unit 22 formed on the substrate 21.

The substrate 21 serves as a support for each part constituting the display device 10, and the upper substrate 9 functions as a protective layer for protecting the organic EL element 1, for example.
In addition, since the display device 10 according to the present embodiment has a configuration for extracting light from the substrate 21 side (bottom emission type), the substrate 21 is substantially transparent (colorless transparent, colored transparent, translucent). The upper substrate 9 is not particularly required to be transparent.

Various glass material substrates are suitable for the substrate 21, but various high-hardness resin substrates can also be used.
On the other hand, the upper substrate 9 is made of, for example, a polyether resin such as a polyimide resin, a polyester resin, a polyamide resin, a polyether ether ketone, or a polyether sulfone other than those listed as the constituent materials of the substrate 21. A substrate configured as a main material can be used. Especially, since the polyimide resin has a small coefficient of thermal expansion and thermal contraction, a substrate mainly made of polyimide resin can keep the thermal contraction rate low. Moreover, the board | substrate comprised using a polyester-type resin as a main material has the advantage that dimensional stability is good.

Furthermore, the shrinkage rate of the upper substrate 9 can be reduced and the dimensional stability can be improved by laminating fillers and fibers in such a resin material, or by adjusting the pre-heat treatment and the degree of crosslinking. .
As the constituent material of the upper substrate 9, in addition to the materials described above, for example, a carbon-based material such as a ceramic material, a metal material, carbon fiber, or the like can be used.

Although the average thickness of the board | substrate 21 is not specifically limited, It is preferable that it is about 1-30 mm, and it is more preferable that it is about 5-20 mm. On the other hand, the average thickness of the upper substrate 9 is not particularly limited, but is preferably about 0.1 to 30 mm, and more preferably about 0.1 to 10 mm.
The circuit unit 22 includes a base protective layer 23 formed on the substrate 21, a driving TFT (switching element) 24 formed on the base protective layer 23, a first interlayer insulating layer 25, and a second interlayer insulating layer. 26.

The driving TFT 24 includes a semiconductor layer 241, a gate insulating layer 242 formed on the semiconductor layer 241, a gate electrode 243 formed on the gate insulating layer 242, a source electrode 244, and a drain electrode 245. ing.
On such a circuit portion 22, the organic EL elements 1 are provided corresponding to the respective driving TFTs 24. Adjacent organic EL elements 1 are partitioned by a partition wall (bank) 31.

In the present embodiment, the anode 3 of each organic EL element 1 constitutes a pixel electrode and is electrically connected to the drain electrode 245 of each driving TFT 24 by the wiring 27. The hole transport layer 5 and the light emitting layer 6 are individually formed for each organic EL element 1, and the cathode 8 is a common electrode.
The display device 10 may be monochromatic display, and color display is also possible by selecting a light emitting material used for each organic EL element 1.

Hereinafter, the organic EL element 1 will be described in detail.
As shown in FIG. 1, the organic EL element 1 includes a positive electrode 3, a negative electrode 8, and a positive hole transport layer 5 and a light emitting layer 6 interposed between the positive electrode 3 and the negative electrode 8 in this order from the positive electrode 3 side. ing.
The anode 3 is an electrode that injects holes into the hole transport layer 5.
As a constituent material (anode material) of the anode 3, it is preferable to use a material having a large work function, excellent conductivity, and translucency.

Examples of such an anode material include ITO (composite of indium oxide and zinc oxide), oxides such as SnO ₂ , Sb-containing SnO ₂ , and Al-containing ZnO, Au, Pt, Ag, Cu, or these. An alloy etc. are mentioned, At least 1 sort (s) of these can be used.
The average thickness of the anode 3 is not particularly limited, but is preferably about 10 to 200 nm, and more preferably about 50 to 150 nm. If the thickness of the anode 3 is too thin, the function as the anode 3 may not be sufficiently exhibited. On the other hand, if the anode 3 is too thick, the light transmittance may be remarkably lowered depending on the type of anode material. When the structure of the organic EL element 1 is a bottom emission type, it may not be suitable for practical use.

As the anode material, for example, a conductive resin material such as polythiophene or polypyrrole can be used.
On the other hand, the cathode 8 is an electrode for injecting electrons into the light emitting layer 6.
As a constituent material (cathode material) of the cathode 8, it is preferable to use a material having a small work function.

Examples of such cathode materials include Li, Mg, Ca, Sr, La, Ce, Er, Eu, Sc, Y, Yb, Ag, Cu, Al, Cs, Rb, and alloys containing these, and the like. At least one of them can be used.
In particular, when an alloy is used as the cathode material, an alloy containing a stable metal element such as Ag, Al, or Cu, specifically, an alloy such as MgAg, AlLi, or CuLi is preferably used. By using such an alloy as a cathode material, the electron injection efficiency and stability of the cathode 8 can be improved.

The average thickness of the cathode 8 is not particularly limited, but is preferably about 100 nm to 3000 nm, and more preferably about 500 to 2000 nm. If the thickness of the cathode 8 is too thin, the function of the cathode 8 may not be sufficiently exhibited. On the other hand, if the cathode 8 is too thick, characteristics such as the light emission efficiency of the organic EL element 1 may be deteriorated.
The hole transport layer 5 has a function of transporting holes injected from the anode 3 to the light emitting layer 6.
As the constituent material (hole transport material) of the hole transport layer 5, various polymer materials and various low molecular materials can be used alone or in combination.

  Examples of the polymer hole transport material include those having an arylamine skeleton such as polyarylamine, those having a fluorene skeleton such as a fluorene-bithiophene copolymer, and fluorene-arylamine copolymers. Those having both arylamine skeleton and fluorene skeleton, poly (N-vinylcarbazole), polyvinylpyrene, polyvinylanthracene, polythiophene, polyalkylthiophene, polyhexylthiophene, poly (p-phenylenevinylene), polytinylenevinylene, pyrene Examples include formaldehyde resin, ethylcarbazole formaldehyde resin, and derivatives thereof.

Moreover, the said compound can also be used as a mixture with another compound. As an example, the polythiophene-containing mixture includes poly (3,4-ethylenedioxythiophene / styrene sulfonic acid) (PEDOT / PSS).
On the other hand, examples of low molecular hole transport materials include 1,1-bis (4-di-para-triaminophenyl) cyclohexane and 1,1′-bis (4-di-para-tolylaminophenyl). ) Arylcycloalkane compounds such as 4-phenyl-cyclohexane, 4,4 ′, 4 ″ -trimethyltriphenylamine, N, N, N ′, N′-tetraphenyl-1,1′-biphenyl- 4,4′-diamine, N, N′-diphenyl-N, N′-bis (3-methylphenyl) -1,1′-biphenyl-4,4′-diamine (TPD1), N, N′-diphenyl -N, N'-bis (3-methoxyphenyl) -1,1'-biphenyl-4,4'-diamine (TPD2), N, N, N ', N'-tetrakis (4-methoxyphenyl) -1 , 1′-biphenyl-4,4′-diamine (TPD3 N, N′-di (1-naphthyl) -N, N′-diphenyl-1,1′-biphenyl-4,4′-diamine (α-NPD), TPTE, 4,4 ′, 4 ″ − An arylamine compound such as tris (1-naphthylphenylamino) triphenylamine (1-TNATA), N, N, N ′, N′-tetraphenyl-para-phenylenediamine, N, N, N ′, N Phenylenediamine compounds such as '-tetra (para-tolyl) -para-phenylenediamine, N, N, N', N'-tetra (meta-tolyl) -meta-phenylenediamine (PDA), carbazole, N- Carbazole compounds such as isopropylcarbazole, N-phenylcarbazole, stilbene, stilbene compounds such as 4-di-para-tolylaminostilbene, oxa compounds such as O _x Z Azole compounds, triphenylmethane, triphenylmethane compounds such as m-MTDATA, pyrazoline compounds such as 1-phenyl-3- (para-dimethylaminophenyl) pyrazoline, benzine (cyclohexadiene) compounds, triazole Such as triazole-based compounds, imidazole-based compounds such as imidazole, 1,3,4-oxadiazole, 2,5-di (4-dimethylaminophenyl) -1,3,4, -oxadiazole Oxadiazole compounds, anthracene, anthracene compounds such as 9- (4-diethylaminostyryl) anthracene, fluorenone, 2,4,7, -trinitro-9-fluorenone, 2,7-bis (2-hydroxy-) 3- (2-Chlorophenylcarbamoyl) -1-naphthyl Zo) fluorenone compounds such as fluorenone, aniline compounds such as polyaniline, silane compounds, pyrrole compounds such as 1,4-dithioketo-3,6-diphenyl-pyrrolo- (3,4-c) pyrrolopyrrole Compounds, fluorene compounds such as fluorene, porphyrins, porphyrin compounds such as metal tetraphenylporphyrin, quinacridone compounds such as quinacridone, phthalocyanine, copper phthalocyanine, tetra (t-butyl) copper phthalocyanine, iron phthalocyanine Metal or metal-free phthalocyanine compounds, copper naphthalocyanine, vanadyl naphthalocyanine, metal or metal-free naphthalocyanine compounds such as monochlorogallium naphthalocyanine, N, N′-di (naphthalen-1-yl) -N N'- diphenyl - benzidine, N, N, N ', benzidine-based compounds such as N'- tetraphenyl benzidine, and the like.

The average thickness of the hole transport layer 5 is not particularly limited, but is preferably about 10 to 150 nm, and more preferably about 50 to 100 nm.
A hole injection layer that improves the efficiency of hole injection from the anode 3 may be provided between the anode 3 and the hole transport layer 5, for example.
As a constituent material (hole injection material) of this hole injection layer, for example, copper phthalocyanine, 4,4 ′, 4 ″ -tris (N, N-phenyl-3-methylphenylamino) triphenylamine ( m-MTDATA) and the like.

  Here, when a current is applied between the anode 3 and the cathode 8 (voltage is applied), holes that have moved through the hole transport layer 5 are injected into the light emitting layer 6, and electrons from the cathode 8 enter the light emitting layer 6. When injected, holes and electrons are recombined in the light emitting layer 6. And in the light emitting layer 6, an exciton (exciton) produces | generates, and when this exciton returns to a ground state, energy (fluorescence and phosphorescence) is discharge | released (light emission).

As a constituent material (light emitting material) of the light emitting layer 6, various polymer materials and various low molecular materials can be used alone or in combination.
Examples of the polymer light-emitting material include polyacetylene compounds such as trans-type polyacetylene, cis-type polyacetylene, poly (di-phenylacetylene) (PDPA), poly (alkyl, phenylacetylene) (PAPA), and poly (para-para-). Fenvinylene) (PPV), poly (2,5-dialkoxy-para-phenylenevinylene) (RO-PPV), cyano-substituted-poly (para-phenvinylene) (CN-PPV), poly (2-dimethyloctyl) Polyparaphenylene vinylene compounds such as silyl-para-phenylene vinylene (DMOS-PPV), poly (2-methoxy, 5- (2′-ethylhexoxy) -para-phenylene vinylene) (MEH-PPV), poly ( 3-alkylthiophene) (PAT), poly (oxypropylene) Polythiophene compounds such as riol (POPT), poly (9,9-dialkylfluorene) (PDAF), α, ω-bis [N, N′-di (methylphenyl) aminophenyl] -poly [9,9- Bis (2-ethylhexyl) fluorene-2,7-diyl] (PF2 / 6am4), poly (9,9-dioctyl-2,7-divinylenefluorenyl-ortho-co (anthracene-9,10-diyl) Polyfluorene compounds such as poly (para-phenylene) (PPP), polyparaphenylene compounds such as poly (1,5-dialkoxy-para-phenylene) (RO-PPP), poly (N-vinyl) Polycarbazole compounds such as carbazole (PVK), poly (methylphenylsilane) (PMPS), poly (naphthylphenylsilane) ( NPS), polysilane-based compounds such as poly (biphenylyl phenyl silane) (pBPS), and the like.

On the other hand, examples of low-molecular light emitting materials include benzene compounds such as distyrylbenzene (DSB) and diaminodistyrylbenzene (DADSB), naphthalene compounds such as naphthalene and nile red, and phenanthrene compounds such as phenanthrene. Compound, chrysene, chrysene compounds such as 6-nitrochrysene, perylene, N, N'-bis (2,5-di-t-butylphenyl) -3,4,9,10-perylene-di-carboximide Perylene compounds such as (BPPC), coronene compounds such as coronene, anthracene compounds such as anthracene and bisstyrylanthracene, pyrene compounds such as pyrene, 4- (di-cyanomethylene) -2-methyl Of 6- (para-dimethylaminostyryl) -4H-pyran (DCM) Such as pyran compounds, acridine compounds such as acridine, stilbene compounds such as stilbene, thiophene compounds such as 2,5-dibenzoxazole thiophene, benzoxazole compounds such as benzoxazole, and benzimidazole Benzoimidazole compounds, benzothiazole compounds such as 2,2 ′-(para-phenylenedivinylene) -bisbenzothiazole, bistyryl (1,4-diphenyl-1,3-butadiene), tetraphenylbutadiene, etc. Butadiene compounds, naphthalimide compounds such as naphthalimide, coumarin compounds such as coumarin, perinone compounds such as perinone, oxadiazole compounds such as oxadiazole, aldazine compounds, 1, 2 , 3 , 4,5-pentaphenyl-1,3-cyclopentadiene (PPCP), a cyclopentadiene compound such as quinacridone and quinacridone red, a pyridine compound such as pyrrolopyridine and thiadiazolopyridine, Spiro compounds such as 2,2 ′, 7,7′-tetraphenyl-9,9′-spirobifluorene, metal or metal-free phthalocyanine compounds such as phthalocyanine (H ₂ Pc), copper phthalocyanine, fluorene Such a fluorene-based compound, 8-hydroxyquinoline aluminum (Alq ₃ ), tris (4-methyl-8 quinolinolate) aluminum (III) (Almq ₃ ), 8-hydroxyquinoline zinc (Znq ₂ ), (1,10-phenanthroline) ) -Tris- (4,4,4-Trif Oro-1- (2-thienyl) - butane-1,3-Jioneto) europium _{(III) (Eu (TTA)} 3 (phen)), factory scan (2-phenylpyridine) iridium (Ir _(ppy) 3), Examples include various metal complexes such as 2,3,7,8,12,13,17,18-octaethyl-21H, 23H-porphine platinum (II).

Although the average thickness of the light emitting layer 6 is not specifically limited, It is preferable that it is about 10-150 nm, and it is more preferable that it is about 50-100 nm.
An electron transport layer having a function of transporting electrons injected from the cathode 8 to the light emitting layer 6 may be provided between the cathode 8 and the light emitting layer 6. Furthermore, an electron injection layer for improving the injection efficiency of electrons from the cathode 8 to the electron transport layer may be provided between the electron transport layer and the cathode 8.

As a constituent material (electron transport material) of the electron transport layer, for example, 1,3,5-tris [(3-phenyl-6-tri-fluoromethyl) quinoxalin-2-yl] benzene (TPQ1), 1,3 , 5-tris [{3- (4-t-butylphenyl) -6-trisfluoromethyl} quinoxalin-2-yl] benzene (TPQ2), a benzene compound (starburst compound), naphthalene, etc. Naphthalene compounds, phenanthrene compounds such as phenanthrene, chrysene compounds such as chrysene, perylene compounds such as perylene, anthracene compounds such as anthracene, pyrene compounds such as pyrene, acridine compounds such as acridine Compounds, stilbene compounds such as stilbene, thiophene compounds such as BBOT Compounds, butadiene compounds such as butadiene, coumarin compounds such as coumarin, quinoline compounds such as quinoline, bistyryl compounds such as bistyryl, pyrazine compounds such as pyrazine and distyrylpyrazine, quinoxaline Quinoxaline compounds, benzoquinone, benzoquinone compounds such as 2,5-diphenyl-para-benzoquinone, naphthoquinone compounds such as naphthoquinone, anthraquinone compounds such as anthraquinone, oxadiazole, 2- (4-biphenylyl) -5- (4-t-butylphenyl) -1,3,4-oxadiazole (PBD), oxadiazole compounds such as BMD, BND, BDD, BAPD, triazole, 3,4,5-tri Of phenyl-1,2,4-triazole Such triazole compounds, oxazole compounds, anthrone compounds such as anthrone, fluorenone, fluorenone compounds such as 1,3,8-trinitro-fluorenone (TNF), diphenoquinone, diphenoquinone compounds such as MBDQ, stilbenequinone , Stilbenequinone compounds such as MBSQ, anthraquinodimethane compounds, thiopyran dioxide compounds, fluorenylidenemethane compounds, diphenyldicyanoethylene compounds, fluorene compounds such as fluorene, phthalocyanine, copper phthalocyanine, Metal or metal-free phthalocyanine compounds such as iron phthalocyanine, 8-hydroxyquinoline aluminum (Alq ₃ ), complexes with benzoxazole and benzothiazole as ligands And various metal complexes.

In addition, as a constituent material (electron transport material) of the electron transport layer, for example, a polymer material such as an oxadiazole polymer (polyoxadiazole) or a triazole polymer (polytriazole) may be used. it can.
Although the average thickness of an electron carrying layer is not specifically limited, It is preferable that it is about 1-100 nm, and it is more preferable that it is about 20-50 nm.

  Examples of the constituent material (electron injection material) of the electron injection layer include 8-hydroxyquinoline, oxadiazole, or derivatives thereof (for example, metal chelate oxinoid compounds containing 8-hydroxyquinoline). In addition, one or more of these can be used in combination (for example, as a multi-layer laminate), and various inorganic insulating materials, various inorganic semiconductor materials, and the like can be used.

By configuring the electron injection layer using an inorganic insulating material or an inorganic semiconductor material as a main material, current leakage can be effectively prevented, electron injection performance can be improved, and durability can be improved.
Examples of such inorganic insulating materials include alkali metal chalcogenides (oxides, sulfides, selenides, tellurides), alkaline earth metal chalcogenides, alkali metal halides, and alkaline earth metal halides. Of these, one or two or more of these can be used in combination. By forming the electron injection layer using these as main materials, the electron injection property can be further improved.

Examples of the alkali metal chalcogenide include Li ₂ O, LiO, Na ₂ S, Na ₂ Se, and NaO.

Examples of the alkaline earth metal chalcogenide include CaO, BaO, SrO, BeO, BaS, MgO, and CaSe.
Examples of the alkali metal halide include CsF, LiF, NaF, KF, LiCl, KCl, and NaCl.
Examples of the alkaline earth metal halide include CaF ₂ , BaF ₂ , SrF ₂ , MgF ₂ , and BeF ₂ .

Examples of the inorganic semiconductor material include an oxide containing at least one element of Ba, Ca, Sr, Yb, Al, Ga, In, Li, Na, Cd, Mg, Si, Ta, Sb, and Zn. , Nitrides, oxynitrides, and the like, and one or more of these can be used in combination.
Moreover, when an electron injection layer is comprised with such an inorganic material, it is preferable that this inorganic material is a microcrystal or an amorphous | non-crystalline substance. Thereby, since the electron injection layer becomes more uniform, pixel defects such as dark spots can be reduced.

In the display device 10 of the present embodiment, after forming a plurality of organic EL elements 1 on the TFT circuit substrate 20, the TFT circuit substrate 20 and the upper substrate 9 are bonded via the organic EL elements 1. However, the organic semiconductor element manufacturing method of the present invention is applied to the formation of the organic EL element 1.
Hereinafter, a method for manufacturing the display device 10 will be described.

[1] First, the TFT circuit substrate 20 is prepared.
[1-A] First, a substrate 21 is prepared, and an average thickness of about 200 to 500 nm is formed on the substrate 21 by, for example, plasma CVD using TEOS (tetraethoxysilane) or oxygen gas as a source gas. A base protective layer 23 composed of silicon oxide as a main material is formed.

[1-B] Next, the driving TFT 24 is formed on the base protective layer 23.
[1-Ba] First, amorphous silicon having an average thickness of about 30 to 70 nm is mainly formed on the base protective layer 23 by the plasma CVD method or the like with the substrate 21 heated to about 350 ° C. A semiconductor film is formed.
[1-Bb] Next, the semiconductor film is crystallized by laser annealing, solid phase growth, or the like to change the amorphous silicon into polysilicon.
Here, in the laser annealing method, for example, a line beam with a beam length of 400 mm is used with an excimer laser, and the output intensity is set to about 200 mJ / cm ² , for example. As for the line beam, the line beam is scanned so that a portion corresponding to 90% of the peak value of the laser intensity in the short dimension direction overlaps each region.

[1-Bc] Next, the semiconductor film is patterned to form islands, and for example, a plasma CVD method using TEOS (tetraethoxysilane) or oxygen gas as a source gas so as to cover each island-shaped semiconductor film 241. Thus, a gate insulating layer 242 composed mainly of silicon oxide or silicon nitride having an average thickness of about 60 to 150 nm is formed.
[1-Bd] Next, a conductive film composed mainly of a metal such as aluminum, tantalum, molybdenum, titanium, or tungsten is formed on the gate insulating layer by, for example, sputtering, and then patterned to form a gate. An electrode 243 is formed.
[1-Be] Next, in this state, high concentration phosphorus ions are implanted to form source / drain regions in a self-aligned manner with respect to the gate electrode 243. Note that a portion where no impurity is introduced becomes a channel region.

[1-C] Next, the source electrode 244 and the drain electrode 245 electrically connected to the driving TFT 24 are formed.
[1-Ca] First, the first interlayer insulating layer 25 is formed so as to cover the gate electrode 243, and then a contact hole is formed.
[1-Cb] Next, the source electrode 244 and the drain electrode 245 are formed in the contact hole.

[1-D] Next, a wiring (relay electrode) 27 that electrically connects the drain electrode 245 and the anode 3 is formed.
[1-Da] First, the second interlayer insulating layer 26 is formed on the first interlayer insulating layer 25, and then contact holes are formed.
[1-Db] Next, a wiring 27 is formed in the contact hole.
As described above, the TFT circuit substrate 20 is obtained.

[2] Next, the organic EL element 1 is formed on the TFT circuit substrate 20.
As described above, the method of manufacturing an organic semiconductor element of the present invention is applied to the formation of the organic EL element 1, and in this embodiment, the first organic semiconductor layer and the first organic semiconductor layer are stacked on the first organic semiconductor layer. As the second organic semiconductor layer to be formed, the hole transport layer 5 and the light emitting layer 6 are formed, respectively.

By applying the method for producing an organic semiconductor element of the present invention to form the hole transport layer 5 and the light emitting layer 6, these constituent materials are formed in the vicinity of the interface between the hole transport layer 5 and the light emitting layer 6. Can be surely prevented from mixing, so that the interface between the hole transport layer 5 and the light emitting layer 6 can be made uniform.
Hereinafter, a method for producing the organic EL element (organic semiconductor element) 1 will be described.

[2-A] First, as shown in FIG. 2A, the anode (pixel electrode) 3 is formed on the second interlayer insulating layer 26 provided in the TFT circuit substrate 20 so as to be in contact with the wiring 27.
The anode 3 can be formed in the same manner as the gate electrode 243.
[2-B] Next, as shown in FIG. 2B, the partition wall 31 is formed on the second interlayer insulating layer 26 so as to partition each anode 3.
The partition wall portion 31 can be formed by forming an insulating film so as to cover the anode 3 and the second interlayer insulating film 26 and then patterning using a photolithography method or the like.

The constituent material of the insulating film (partition wall 31) is selected in consideration of heat resistance, liquid repellency, ink solvent resistance, adhesion to the underlayer, and the like.
Examples of such materials include organic materials such as acrylic resins and polyimide resins, and inorganic materials such as SiO ₂ .
In particular, when the anode 3 is composed of an oxide material as a main material, it is preferable to use SiO ₂ as a constituent material of the partition wall 31. Thereby, the adhesiveness of the anode 3 and the partition part 31 can be improved.

Moreover, the partition part 31 which shows liquid repellency can be obtained, for example by forming using a fluorine-type resin, or performing the fluorine plasma process to the surface of the partition part 31.
Further, the shape of the opening of the partition wall 31 may be any shape such as, for example, a circle, an ellipse, a quadrangle, or a polygon such as a hexagon.
In addition, when making the shape of opening of the partition part 31 into a polygon, it is preferable that the corner | angular part is roundish. Thus, when the hole transport layer 5 and the light emitting layer 6 are formed using the first liquid material and the second liquid material as described later, these liquid materials are placed inside the partition wall portion 31. It can be reliably supplied to every corner of the space.
The height of the partition wall 31 is appropriately set according to the total thickness of the anode 3, the hole transport layer 5, and the light emitting layer 6, and is not particularly limited, but is preferably about 30 to 500 nm. By having such a height, the function as a partition (bank) is sufficiently exhibited.

[2-C] Next, as shown in FIG. 2C, the hole transport layer 5 and the light emitting layer 6 are formed on the respective anodes 3 so as to be laminated in this order.
Hereinafter, this process will be described with reference to FIG.
[2-Ca] First, a hole transport layer forming material (first liquid material) in which the hole transport material (first organic semiconductor material) described above is dissolved or dispersed in the first liquid, and the first liquid. A light emitting layer forming material (second liquid material) in which the light emitting material (second organic semiconductor material) is dissolved or dispersed in a second liquid that is substantially incompatible with the liquid is prepared (second liquid material). Step 1).
Here, the first liquid and the second liquid are selected so as not to be substantially compatible with each other. The combination of the first liquid and the second liquid is not particularly limited. For example, when a polar solvent is used as the first liquid, the first liquid (polarity) is used as the second liquid. A solvent having a polarity lower than that of the solvent may be selected. By making such a combination of the first liquid and the second liquid, it is possible to accurately prevent or suppress the compatibility of the first liquid and the second liquid.

  Examples of polar solvents include various inorganic solvents such as water, carbon disulfide, and ethylene carbonate, alcohol solvents such as methanol, ethanol, isopropanol, ethylene glycol, diethylene glycol (DEG), and glycerin, methyl cellosolve, ethyl cellosolve, and phenyl. Examples include cellosolve solvents such as cellosolve, carbonyl solvents such as acetone and formaldehyde, and amine solvents such as ethylamine, diethylamine, pyridine, and piperidine. One or more of these can be used in combination. .

In addition, when water is selected as the first liquid among such polar solvents, examples of the second liquid include dichloromethane, trichloromethane, carbon tetrachloride, 1,1-dichloroethane, 1, Halogen compound solvents such as 2-dichloroethane, 1,1,1-trichloroethane and pentachloroethane, aromatic hydrocarbon solvents such as toluene, xylene and benzene, ether solvents such as diethyl ether, diisopropyl ether and anisole, hexane, Aliphatic solvents such as cyclohexane, cyclohexanol and cyclohexanone, ester solvents such as ethyl acetate, n-propyl acetate and iso-propyl acetate, and alcohol solvents such as 1-pentanol and phenol can be used. Thereby, it can prevent or suppress that a 1st liquid and a 2nd liquid are compatible.
In the following, water is used as the first liquid, and any of the halogen compound solvents, aromatic hydrocarbon solvents, ether solvents, aliphatic solvents and ester solvents as described above is used as the second liquid. A case where these are used will be described as a representative.

<< first liquid material >>
Here, when water is used as the first liquid, the hole transport layer forming material (first liquid material) is usually the hole transport material (first organic semiconductor material) as described above. It is obtained by dispersing 51 in the first liquid.
Such a material for forming a hole transport layer contains a dispersant 52 that improves the dispersibility of the hole transport material in water (first liquid) as in this embodiment. Is preferred. As a result, as shown in FIG. 3A, since the micelle 55 obtained by surrounding the hole transport material 51 with the dispersant 52 is formed in water, the hole transport material 51 is reliably dispersed in water. Can be made.

In addition, as a dispersion liquid (1st liquid) obtained by including such a dispersing agent 52, suspension (suspension), an emulsion (emulsion, emulsion, emulsion-like liquid) etc. are mentioned, for example. However, any of these may be used.
Examples of such a dispersant 52 include nonionic (nonionic) dispersants, anionic dispersants, cationic dispersants, and amphoteric dispersants.

Examples of nonionic (nonionic) dispersants include ether dispersants, ester dispersants, ether ester dispersants, alkylamine dispersants, nitrogen-containing dispersants, and the like.
Examples of the anionic dispersant include various rosins, various carboxylates, various sulfates, various sulfonates, and various phosphates.

Examples of the cationic dispersant include various ammonium salts such as primary ammonium salt, secondary ammonium salt, tertiary ammonium salt, and quaternary ammonium salt.
Examples of the amphoteric dispersant include various betaines such as carboxybetaine and sulfobetaine, various aminocarboxylic acids, and various phosphate ester salts.
Among these, as the dispersant 52, it is preferable to use a cationic dispersant or a nonionic dispersant. Thereby, in the post-process [2-Cd], when the hole transport layer 5 and the light emitting layer 6 are collectively formed, even if the dispersant 52 remains in the hole transport layer 5, It is possible to reliably prevent holes from being trapped, and to transport holes in the hole transport layer 5 to the light emitting layer 6 with certainty.

The mixing ratio of the hole transport material 51 and the dispersant 52 in the hole transport layer forming material is preferably about 10: 1 to 50: 1 by weight, and about 20: 1 to 40: 1. More preferably. Thereby, since the micelle 55 having a more appropriate size is formed in water, the hole transport material 51 can be more reliably dispersed in water (first liquid).
The total content of the hole transport material 51 and the dispersant 52 in the hole transport layer forming material is preferably about 20 to 1 wt% / vol, and about 8 to 2 wt% / vol. Is more preferable. If the total content of the hole transport material 51 and the dispersant 52 is too small, the proportion of water (first liquid) increases accordingly, which is long for removing water in the post-process [2-Cd]. Time is required, and the production efficiency may be reduced. On the other hand, if the total content of the hole transport material 51 and the dispersant 52 is too large, the micelle 55 cannot be formed, and the hole transport material 51 is uniformly dispersed in the first liquid. May be difficult.

<< second liquid material >>
Next, as the second liquid, any one of the halogen compound solvent, the aromatic hydrocarbon solvent, the ether solvent, the aliphatic solvent and the ester solvent as described above is selected. A material having a high solubility of the light emitting material (second organic semiconductor material) is preferably used.

  Further, the second liquid is preferably selected so that the difference in boiling point from the first liquid is as small as possible. The boiling point of the first liquid (water) is A [° C.] When the boiling point of the liquid 2 is B [° C.], it is preferable that | A−B | is 75 or less, more preferably | A−B | is 50 ° C. or less. . By setting the difference between the boiling point of the first liquid (water) and the boiling point of the second liquid as small as possible, the first liquid and the second liquid are removed almost simultaneously in the post-process [2-Cd]. Therefore, the effect of performing the two-layer separation is reliably obtained, and the hole transport material 51 and the light emitting material 61 are mixed in the vicinity of the interface between the hole transport layer 5 and the light emitting layer 6 to be formed. Can be prevented or suppressed accurately. On the other hand, if the difference between the boiling point of the first liquid (water) and the boiling point of the second liquid is too large, it takes a long time to remove the liquid having the higher boiling point in the post-process [2-Cd], and the production efficiency There is a risk of lowering.

  In addition, the content of the light emitting material 61 in the light emitting layer forming material is preferably about 20 to 1 wt% / vol, and more preferably about 8 to 2 wt% / vol. If the content ratio of the light emitting material 61 is too small, the proportion of the second liquid increases accordingly, so that it takes a long time to remove the second liquid in the post-process [2-Cd], resulting in a decrease in manufacturing efficiency. May be incurred. On the other hand, if the content of the light emitting material 61 is too large, it may be difficult to uniformly dissolve the light emitting material 61 in the second liquid.

[2-Cb] Next, as shown in FIG. 3A, on the anode 3 formed on the TFT circuit substrate 20 exposed in the partition wall 31, the hole transport layer forming material (first The liquid material is supplied to form the first liquid film 5 ′ (second step).
As a method for supplying the hole transport layer forming material (first liquid material), for example, an inkjet method (droplet discharge method), a spin coating method, a casting method, a micro gravure coating method, a gravure coating method, a bar coating Examples include various coating methods such as a coating method, a roll coating method, a wire bar coating method, a dip coating method, a spray coating method, a screen printing method, a flexographic printing method, an offset printing method, and a micro contact printing method.

Among these, it is preferable to select a method capable of supplying the hole transport layer forming material as droplets on the anode 3. Thereby, since the hole transport layer forming material can be selectively supplied into the partition wall 31, waste of the hole transport layer forming material can be omitted.
Specifically, as a method of supplying the hole transport layer forming material as droplets, for example, an inkjet method (droplet discharge method) can be given. By using the inkjet method, the amount of the hole transport layer forming material supplied into the partition wall portion 31 can be controlled relatively easily. Therefore, the hole transport layer formed in the post-process [2-Cd] 5 can be made thinner and the pixel size can be reduced.

[2-Cc] Next, as shown in FIG. 3B, the first liquid coating 5 ′ exposed in the partition wall 31 in a state where the first liquid coating 5 ′ does not solidify, A light emitting layer forming material (second liquid material) is supplied to form a second liquid film 6 '(third step).
As described above, since the first liquid and the second liquid are selected to be substantially incompatible, the first liquid film 5 'and the second liquid film 6' are mixed. Thus, the first liquid coating 5 ′ and the second liquid coating 6 ′ can be reliably formed.

  Furthermore, in this embodiment, since the dispersant 52 is contained in the hole transport layer forming material (first liquid material), as shown in FIG. The first liquid coating 5 ′ and the second liquid coating 6 ′ are arranged at the interface. As a result, it is possible to reliably prevent the hole transport layer forming material and the light emitting layer forming material from repelling each other at this interface, and the first liquid coating 5 ′ and the second liquid coating 6 ′. The interface can be made uniform.

Further, the dispersant 52 has a function as a barrier layer that prevents the micelle 55, that is, the hole transport material 51 from moving to the light emitting layer forming material side and the light emitting material 61 from moving to the hole transport layer forming material side. Therefore, the interface between the hole transport layer 5 and the light emitting layer 6 formed in the next step [2-Cd] can be made more uniform.
As a method of supplying the second liquid material, various coating methods can be used. For the same reason as described above, the light emitting layer forming material is formed as droplets on the first liquid film 5 ′. It is preferable to select a method that can be supplied. In addition, when the light emitting layer forming material of plural colors is provided by supplying the light emitting layer forming material as droplets, there is an advantage that the pattern can be easily applied for each color.

  In the present specification, “the state in which the first liquid coating 5 ′ does not solidify” means that the first liquid contained in the first liquid coating 5 ′ has not been completely removed. That is, it means a state that is not completely solidified, and includes a semi-solidified state. However, after the first liquid film 5 ′ is formed by supplying the first liquid material, the concentration of the hole transport material (first organic semiconductor material) is reduced by volatilization of water (first liquid). The light emitting layer forming material (second liquid material) may be supplied until it rises preferably 50%, more preferably 20%. Thereby, the effect acquired when forming the positive hole transport layer 5 and the light emitting layer 6 collectively will be exhibited notably.

[2-Cd] Next, the first liquid (water) and the second liquid are removed from the first liquid film 5 ′ and the second liquid film 6 ′ to solidify these films. The hole transport layer (first organic semiconductor layer) 5 and the light emitting layer (second organic semiconductor layer) 6 are collectively formed (fourth step).
As shown in FIG. 3C, the first liquid and the second liquid are removed by bringing the flat plate 65 into contact with the second liquid film 6 ′, and then the first liquid film 5 ′ and It is preferable to carry out in a state where the distance between the flat plate 65 and the TFT circuit substrate 20 is defined (approached) so that the second liquid film 6 ′ is layered. As a result, the second liquid film 6 ′ and the first liquid film 5 ′ are removed from the second liquid and the first liquid in a state where the thickness thereof is substantially uniform. As shown in FIG. 3D, the film thicknesses of the light emitting layer 6 and the hole transport layer 5 to be formed are substantially uniform.

As the constituent material of the flat plate 65, the same material as described in the constituent material of the upper substrate 9 can be used.
The flat plate 65 preferably has liquid repellency on the second liquid film 6 ′, that is, the surface to be brought into contact with the light emitting layer forming material. Thereby, in this process, after forming the hole transport layer 5 and the light emitting layer 6 collectively, the flat plate 65 can be easily removed from the light emitting layer 6 as shown in FIG.3 (e).

As a method for imparting liquid repellency to the flat plate 65, various methods can be used. For example, a fluorine resin material such as polytetrafluoroethylene (PTFE) on the surface to be brought into contact with the light emitting layer forming material. And a method of forming a liquid repellent film composed of a silane coupling agent having liquid repellency and the like.
In this way, the first liquid and the second liquid are removed from the respective films in a state where the film thickness of the first liquid film 5 ′ and the film thickness of the second liquid film 6 ′ are substantially uniform. Here, as described above, the first liquid and the second liquid are selected so that they are not substantially compatible with each other. Therefore, while maintaining this state, the hole transport layer 5 and The light emitting layer 6 is formed. That is, since the interface between the first liquid coating 5 ′ and the second liquid coating 6 ′ is uniformly formed, the hole transport layer obtained by removing the solvent or the dispersion medium from these liquid coatings 5 and the light emitting layer 6 are also uniform. As a result, the transfer of holes from the hole transport layer 5 to the light emitting layer 6 is performed smoothly, and the resulting organic EL element 1 exhibits excellent characteristics such as luminous efficiency.

  Furthermore, in this embodiment, a dispersion liquid in which micelles 55 composed of a hole transport material 51 and a dispersant 52 are dispersed in water is used as a hole transport layer forming material, and water is used as a light emitting layer forming material. Also, a solution in which the light emitting material 61 is dissolved in the second liquid having low polarity is used. In this case, the micelle 55 exists with the polar group contained in the dispersant 52 facing outward. Therefore, it is possible to favorably inhibit the micelle 55 from moving to the second liquid film 6 ′ configured using the second liquid having a polarity lower than that of water as a solvent.

  The light emitting material 61 is present in a dissolved state in the second liquid. In order to shift from such a stable state to a more unstable state in which the light emitting material 61 is dispersed in water, more energy is required. Therefore, it is possible to suitably inhibit the light emitting material 61 from moving to the first liquid film 5 ′ configured using water (polar solvent) as a dispersion medium.

  The method for removing the first liquid (water) and the second liquid is not particularly limited, and may be performed by natural drying, but the first liquid film (first liquid material) may be used. It is preferable to carry out by heating and / or depressurizing 5 ′ and the second liquid coating (second liquid material) 6 ′. Thus, the hole transport material 51 is prevented or suppressed from unintentionally diffusing to the second liquid film 6 ′ side and the light emitting material 61 to the first liquid material 5 ′ side. The liquid coating 5 ′ and the second liquid coating 6 ′ can be quickly solidified. In addition, the manufacturing process time can be shortened, and the dispersant 52 can be suitably prevented or suppressed from remaining in the first liquid film 5 ′.

  The heating temperature should be the lower one of the glass transition temperature (Tg) of the first organic semiconductor material and the second organic semiconductor material, or a temperature lower than the glass transition temperature. Preferably, it varies slightly depending on the first organic semiconductor material and the second organic semiconductor material, and is not particularly limited, but is preferably about 60 to 200 ° C, more preferably about 90 to 150 ° C.

Moreover, the pressure of the atmosphere at the time of depressurization is not particularly limited, but is preferably about 10 to 10 ⁵ Pa, and more preferably about 10 ³ to 10 ⁴ Pa.
Furthermore, the time for heating and / or depressurizing the first liquid coating 5 ′ and the second liquid coating 6 ′ varies slightly depending on the type of the second liquid selected, but is about 10 to 120 minutes. Preferably, it is about 30 to 90 minutes.

  By setting the conditions for heating and / or depressurizing the first liquid film 5 ′ and the second liquid film 6 ′ within such ranges, the first organic semiconductor material and the second organic semiconductor material are altered. -Preventing or suppressing the hole transport material 51 from unintentionally diffusing to the second liquid film 6 'side and the light emitting material 61 unintentionally diffusing to the first liquid material 5' side while reliably preventing deterioration. Thus, the first liquid coating 5 ′ and the second liquid coating 6 ′ can be rapidly solidified.

When the first liquid, the second liquid, the first organic semiconductor material and the second organic semiconductor material, and the first liquid film 5 ′ and the second liquid film 6 ′ are heated and / or decompressed. The relationship with these conditions can be obtained experimentally in advance.
In addition, when removing the first liquid (water) and the second liquid by heating, the heating is preferably performed from the second liquid film 6 ′ (flat plate 65) side. As a result, the removal of the second liquid is performed at a slightly shorter interval (time lag) than the removal of the first liquid (water), so that the hole transport layer 5 is formed after the light emitting layer 6 is formed. Will be formed. Here, generally, when the dispersion and the solution are brought into contact with each other, the probability a that the dispersion in the dispersion moves into the solution and the probability b that the solution in the solution moves into the dispersion. Are compared, the probability a is considered to be higher. Therefore, when the configuration of the first liquid coating 5 ′ and the second liquid coating 6 ′ is as in the present embodiment, the hole transport layer 5 is formed after the light emitting layer 6 is formed. This can more reliably prevent the hole transport material 51 from diffusing (transferring) into the light emitting layer 6.

[2-D] Next, as shown in FIG. 2D, each common layer is formed on each light emitting layer 6 and each partition wall 31, that is, so as to cover each light emitting layer 6 and each partition wall 31. A cathode 8 is formed.
The cathode 8 is formed by, for example, a vapor phase process using a sputtering method, a vacuum deposition method, a CVD method, a spin coating method (pyrosol method), a casting method, a micro gravure coating method, a gravure coating method, a bar coating method, a roll. It can be formed by a liquid phase process using a coating method, a wire bar coating method, a dip coating method, a spray coating method, a screen printing method, a flexographic printing method, an offset printing method, an inkjet printing method, or the like.

These methods are selected in consideration of the physical stability and / or chemical characteristics such as thermal stability of the constituent material of the cathode 8 and solubility in a solvent.
In the present embodiment, since the cathode 8 is formed on the entire surface of the light emitting layer 6 and the partition wall portion 31, it is not necessary to use a mask. For this formation, a vapor phase process using a vacuum evaporation method or the like is used. Are preferably used.
As described above, the organic EL element 1 is manufactured.

  In addition, although this embodiment demonstrated the case where the hole transport layer 5 and the light emitting layer 6 with which the organic EL element 1 was equipped were formed with the manufacturing method of the organic-semiconductor element of this invention, it is limited to such a case. For example, when the organic EL element 1 includes the electron transport layer as described above, the method for producing an organic semiconductor element of the present invention can be applied to the formation of the electron transport layer and the light emitting layer 6.

[3] Next, an upper substrate 9 is prepared, and the cathode 8 and the upper substrate 9 are bonded so that the upper substrate 9 covers the cathode 8 as shown in FIG.
The cathode 8 and the upper substrate 9 can be joined by drying the adhesive in a state where an epoxy adhesive is interposed between the cathode 8 and the upper substrate 9.
The upper substrate 9 has a function as a protective substrate for protecting the organic EL element 1. By providing such an upper substrate 9 on the cathode 8, it is possible to prevent or reduce the contact of the organic EL element 1 with oxygen or moisture, so that the reliability of the organic EL element 1 can be improved and the deterioration and deterioration of the organic EL element 1 can be prevented. Effects such as prevention can be obtained.
The display device 10 can be manufactured through the steps as described above.

  As described above, in the method for manufacturing an organic semiconductor element of the present invention, the first organic semiconductor layer and the second organic semiconductor layer that are collectively formed are both an organic semiconductor layer and an organic insulator layer. A combination in which either one is an organic semiconductor layer and the other is an organic insulator layer is particularly suitable for application to the case where both are organic semiconductor layers. In this case, the effect of the present invention is more remarkably exhibited.

  In addition, as a case where all are organic-semiconductor layers, it can apply to a photoelectric conversion element like a solar cell other than a light emitting element like the organic EL element 1 demonstrated in this embodiment, for example. In addition, when either one is an organic semiconductor layer and the other is an organic insulator layer, it can be applied to a switching element such as an organic thin film transistor (organic TFT).

<Electronic equipment>
Such a display device (organic semiconductor device of the present invention) 10 can be incorporated into various electronic devices.
FIG. 4 is a perspective view showing a configuration of a mobile (or notebook) personal computer to which the electronic apparatus of the present invention is applied.

In this figure, a personal computer 1100 includes a main body 1104 provided with a keyboard 1102 and a display unit 1106 provided with a display. The display unit 1106 is rotatable with respect to the main body 1104 via a hinge structure. It is supported by.
In the personal computer 1100, the display unit included in the display unit 1106 is configured by the display device 10 described above.

FIG. 5 is a perspective view showing a configuration of a mobile phone (including PHS) to which the electronic apparatus of the present invention is applied.
In this figure, a cellular phone 1200 includes a plurality of operation buttons 1202, an earpiece 1204 and a mouthpiece 1206, and a display unit.
In the mobile phone 1200, the display unit is configured by the display device 10 described above.

FIG. 6 is a perspective view showing the configuration of a digital still camera to which the electronic apparatus of the present invention is applied. In this figure, connection with an external device is also simply shown.
Here, an ordinary camera sensitizes a silver halide photographic film with a light image of a subject, whereas a digital still camera 1300 photoelectrically converts a light image of a subject with an imaging device such as a CCD (Charge Coupled Device). An imaging signal (image signal) is generated.

A display unit is provided on the back of a case (body) 1302 in the digital still camera 1300, and is configured to display based on an imaging signal from the CCD, and functions as a finder that displays an object as an electronic image.
In the digital still camera 1300, the display unit is configured by the display device 10 described above.

A circuit board 1308 is installed inside the case. The circuit board 1308 is provided with a memory that can store (store) an imaging signal.
A light receiving unit 1304 including an optical lens (imaging optical system), a CCD, and the like is provided on the front side of the case 1302 (on the back side in the illustrated configuration).
When the photographer confirms the subject image displayed on the display unit and presses the shutter button 1306, the CCD image pickup signal at that time is transferred and stored in the memory of the circuit board 1308.

  In the digital still camera 1300, a video signal output terminal 1312 and an input / output terminal 1314 for data communication are provided on the side surface of the case 1302. As shown in the figure, a television monitor 1430 is connected to the video signal output terminal 1312 and a personal computer 1440 is connected to the data communication input / output terminal 1314 as necessary. Further, the imaging signal stored in the memory of the circuit board 1308 is output to the television monitor 1430 or the personal computer 1440 by a predetermined operation.

  In addition to the personal computer (mobile personal computer) in FIG. 4, the mobile phone in FIG. 5, and the digital still camera in FIG. 6, the electronic apparatus of the present invention includes, for example, a television, a video camera, a viewfinder type, Monitor direct-view video tape recorder, laptop personal computer, car navigation system, pager, electronic notebook (including communication function), electronic dictionary, calculator, electronic game device, word processor, workstation, video phone, security TV Monitors, electronic binoculars, POS terminals, devices equipped with touch panels (for example, cash dispensers and automatic ticket vending machines for financial institutions), medical devices (for example, electronic thermometers, blood pressure monitors, blood glucose meters, electrocardiographs, ultrasound diagnostic devices, internal Endoscope display device), fish finder, various measuring instruments, Vessels such (e.g., gages for vehicles, aircraft, and ships), a flight simulator, various monitors, and a projection display such as a projector.

As mentioned above, although the manufacturing method of the organic-semiconductor element, organic-semiconductor element, organic-semiconductor apparatus, and electronic device of this invention were demonstrated based on embodiment of illustration, this invention is not limited to these.
Moreover, the manufacturing method of the organic-semiconductor element of this invention may add the process of the arbitrary objective 1 or 2 or more.

Next, specific examples of the present invention will be described.
1. Manufacture of Display Devices In each of the following examples and comparative examples, 10 display devices were manufactured.
Example 1
[Preparation of material for forming hole transport layer]
First, as a hole transport material, N, N′-diphenyl-N, N′-bis (3-methoxyphenyl) -1,1′-biphenyl-4,4′-diamine (TPD2) (molecular weight: 488) is used. Used, TPD2 was dissolved in xylene to prepare a 5.0 wt% xylene solution of TPD2.

  Next, pure water was added to the 5.0 wt% xylene solution of TPD2 so that the volume ratio was 1: 2, and the resulting mixture was stirred and used as a dispersant so as to be 5.0 wt% with respect to TPD2. Alkylamine-based dispersant (manufactured by Lion, “Esomine S / 25”) was added dropwise. Then, the hole transport layer forming material (emulsion) was prepared by stirring the mixture obtained here at 100 degreeC for 30 minute (s).

[Preparation of light emitting layer forming material]
As the luminescent material, poly (9,9-dioctyl-2,7-divinylenefluorenyl-ortho-co (anthracene-9,10-diyl) (weight average molecular weight 200000) was used, and this was xylene (boiling point: And dissolved in a 0.1 wt% xylene solution of poly (9,9-dioctyl-2,7-divinylenefluorenyl-ortho-co (anthracene-9,10-diyl). A layer forming material was obtained.

[Manufacture of display devices]
<1A> First, a transparent glass substrate having an average thickness of 5 mm was prepared, and a circuit portion was formed on the glass substrate as described above.
<2A> Next, an ITO film having an average thickness of 100 nm was formed on the circuit portion by vacuum deposition, and then an anode (pixel electrode) was obtained by photolithography and etching.

<3A> Next, after applying polyimide (insulating photosensitive resin) so as to cover the edge of each anode, a partition wall portion was formed by exposure.
<4A> Next, the hole transport layer forming material prepared here is supplied to the inside of the partition wall by an ink jet method, and the liquid film is formed on the anode with the hole transport layer forming material. Formed.

<5A> Next, the electron transport layer forming material prepared here is supplied to the inner side of the partition wall by an ink jet method, and the light emitting layer is formed on the liquid film composed of the hole transport layer forming material. A liquid film composed of the material for use was formed.
<6A> Next, after a glass flat plate subjected to surface treatment with polytetrafluoroethylene is brought into contact with a liquid film composed of the light emitting layer forming material, the film thickness of these liquid films is constant. Then, a glass flat plate was moved closer to the glass substrate side.

<7A> Next, a liquid film and a light emitting layer forming material composed of a hole transport layer forming material by heating from a glass flat plate side with a heater at 140 ° C. for 60 minutes under atmospheric pressure. The liquid film comprised of was solidified. As a result, a hole transport layer having an average thickness of 70 nm and a light emitting layer having an average thickness of 60 nm were collectively formed on the anode.
<8A> Next, Al was supplied by a vacuum deposition method so as to cover the partition wall and the light emitting layer, thereby forming a cathode (common electrode) having an average thickness of 1500 nm.
<9A> Also, a polyimide substrate having an average thickness of 0.5 mm is prepared, and this polyimide substrate is bonded onto the cathode via an epoxy adhesive, whereby a display device similar to that shown in FIG. 1 is obtained. Obtained.

(Example 2)
A display device was manufactured in the same manner as in Example 1 except that the heating in the step <7A> was performed in an atmosphere of 10 ³ Pa.
(Example 3)
A display device was manufactured in the same manner as in Example 1 except that the heating in the step <7A> was changed to 60 ° C. × 120 minutes under conditions of atmospheric pressure.

Example 4
Instead of TPD2, poly (3,4-ethylenedioxythiophene / styrene sulfonic acid) (PEDOT / PSS) (weight average molecular weight 120,000) is used as the hole transport material used for the preparation of the hole transport layer forming material. A display device was manufactured in the same manner as in Example 1 except that was used.

(Example 5)
A display device was produced in the same manner as in Example 1 except that diethyl ether (boiling point: 34.5 ° C.) was used instead of xylene as the second liquid used for preparing the light emitting layer forming material. .
(Example 6)
As a dispersant used for the preparation of the hole transport layer forming material, instead of the alkylamine-based dispersant, polyethylene glycol which is one kind of nonionic dispersant (manufactured by Wako Pure Chemical Industries, average polymerization degree n = 10-50) A display device was manufactured in the same manner as in Example 1 except that.

(Comparative Example 1)
[Preparation of material for forming hole transport layer]
First, as a hole transport material, N, N′-diphenyl-N, N′-bis (3-methoxyphenyl) -1,1′-biphenyl-4,4′-diamine (TPD2) (molecular weight: 488) is used. Used, TPD2 was dissolved in xylene to prepare a 5.0 wt% xylene solution of TPD2 to obtain a hole transport layer forming material.

[Preparation of light emitting layer forming material]
As the luminescent material, poly (9,9-dioctyl-2,7-divinylenefluorenyl-ortho-co (anthracene-9,10-diyl) (weight average molecular weight 200000) was dissolved in xylene. To prepare a light emitting layer forming material by preparing a 0.1 wt% xylene solution of poly (9,9-dioctyl-2,7-divinylenefluorenyl-ortho-co (anthracene-9,10-diyl). It was.

[Manufacture of display devices]
<1B> First, a transparent glass substrate having an average thickness of 5 mm was prepared, and a circuit portion was formed on the glass substrate as described above.
<2B> Next, an ITO film having an average thickness of 100 nm was formed on the circuit portion by vacuum deposition, and then an anode (pixel electrode) was obtained by photolithography and etching.

<3B> Next, after applying polyimide (insulating photosensitive resin) so as to cover the edge of each anode, a partition wall portion was formed by exposure.
<4B> Next, after the hole transport layer forming material prepared here is supplied to the inside of the partition wall by an inkjet method, the material is dried to form a hole transport layer having an average thickness of 70 nm on the anode. Formed.

<5B> Next, the electron transport layer forming material prepared here is supplied to the inside of the partition wall portion by an inkjet method, and then dried, and the electron transport layer having an average thickness of 60 nm is formed on the hole transport layer. Formed.
<6B> Next, Al was supplied by a vacuum deposition method so as to cover the partition wall and the light emitting layer, thereby forming a cathode (common electrode) having an average thickness of 1500 nm.
<7B> Also, a polyimide substrate having an average thickness of 0.5 mm is prepared, and this polyimide substrate is bonded to the cathode via an epoxy adhesive, whereby a display device similar to that shown in FIG. 1 is obtained. Obtained.

(Comparative Example 2)
[Preparation of material for forming hole transport layer]
First, TPD2 (molecular weight: 488) is used as a hole transport material, polyester acrylate compound (“Aronix M-8030” manufactured by Toagosei Co., Ltd.) is used as a photocrosslinking agent, TPD2, polyester acrylate compound, and light A radical polymerization initiator (“Irgacure 651” manufactured by Nagase Sangyo Co., Ltd.) was mixed with dichloroethane at a weight ratio of 30: 65: 5 to obtain a material for forming a hole transport layer.

[Manufacture of display devices]
A display device was manufactured in the same manner as in Comparative Example 1 except that the step <4B> was changed as follows.
<4B ′> Next, the hole transport layer forming material prepared here was supplied to the inside of the partition wall by an inkjet method, and then dried.
Then, the polyester acrylate compound is crosslinked by irradiating ultraviolet rays having a wavelength of 185 nm and an irradiation intensity of 3 mW / cm ^{2 in} the atmosphere for 400 seconds using a filter in a mercury lamp (USHIO Corporation, “UM-452 type”). Thus, a hole transport layer having an average thickness of 70 nm was formed.

(Comparative Example 3)
[Preparation of material for forming hole transport layer]
First, the following compound (A) is used as a hole transport material, and the compound (A) and a photo radical polymerization initiator (“Irgacure 651” manufactured by Nagase Sangyo Co., Ltd.) are converted into dichloroethane at a weight ratio of 95: 5. By dissolving, a material for forming a hole transport layer was obtained.
[Manufacture of display devices]
Except that a hole transport layer having an average thickness of 70 nm was formed by polymerizing the compound (A) using the hole transport layer forming material prepared here, the same as in Comparative Example 2, A display device was manufactured.

2. Evaluation Regarding the organic EL elements included in the display devices of the examples and comparative examples, the light emission luminance (cd / m ² ) and the maximum light emission efficiency (lm / W) are measured, and the light emission luminance is reduced to half of the initial value. The time (half-life) was measured.
The measurement of light emission luminance was performed by applying a voltage of 6 V between the ITO electrode and the AlLi electrode.
Then, with each measurement value (emission luminance, maximum luminous efficiency, half-life) measured in Comparative Example 1 as a reference value, each measurement value measured in each Example and each Comparative Example is divided into the following four stages. Evaluation was performed according to the criteria.

A: The measurement value of Comparative Example 1 is 1.50 times or more. O: The measurement value of Comparative Example 1 is 1.25 times or more and less than 1.50 times. Δ: The measurement value of Comparative Example 1 In contrast, 1.00 times or more and less than 1.25 times x: 0.75 times or more and less than 1.00 times with respect to the measured value of Comparative Example 1 Table 1 shows.

As shown in Table 1, all of the organic EL elements included in the display devices of the respective examples are compared with the organic EL elements included in the display devices of the comparative examples. Excellent results were obtained.
Thereby, in the organic semiconductor element of the present invention, it became clear that the phase dissolution in the vicinity of the interface between the hole transport layer and the light emitting layer was suitably prevented, and a uniform interface was formed.
In addition, it is presumed that the occurrence of interaction between the hole transport materials, which occurs when the hole transport materials are subjected to a polymerization reaction or by fixing the hole transport material with a crosslinking agent, is also preferably suppressed. It was.

It is a longitudinal cross-sectional view which shows an example of the active matrix type display apparatus to which the organic semiconductor device of this invention is applied. It is a figure (longitudinal sectional drawing) for demonstrating the manufacturing method of the active matrix type display apparatus shown in FIG. It is a figure (schematic diagram) for demonstrating the manufacturing method of the active matrix type display apparatus shown in FIG. 1 is a perspective view showing a configuration of a mobile (or notebook) personal computer to which an electronic apparatus of the present invention is applied. It is a perspective view which shows the structure of the mobile telephone (PHS is also included) to which the electronic device of this invention is applied. It is a perspective view which shows the structure of the digital still camera to which the electronic device of this invention is applied.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Organic EL element 3 ... Anode 5 ... Hole transport layer 5 '... 1st liquid film 51 ... Hole transport material 52 ... Dispersant 55 ... Micelle 6 ... Light emitting layer 6' ... ... Second liquid coating 61 ... Luminescent material 65 ... Flat plate 8 ... Cathode 9 ... Upper substrate 10 ... Display device 20 ... TFT circuit board 21 ... Substrate 22 ... Circuit part 23 ... Underlayer protection layer 24 …… Drive TFT 241 …… Semiconductor layer 242 …… Gate insulating layer 243 …… Gate electrode 244 …… Source electrode 245 …… Drain electrode 25 …… First interlayer insulating layer 26 …… Second interlayer insulating layer 27 ... ... Wiring 31 ... Bulkhead 1100 ... Personal computer 1102 ... Keyboard 1104 ... Main body 1106 ... Display unit 1200 ... Mobile phone 1202 ... Operation buttons 1204 ... Earpiece 1206 ... Sending 1300 …… Digital still camera 1302 …… Case (body) 1304 …… Light receiving unit 1306 ………… Shutter button 1308 …… Circuit board 1312 …… Video signal output terminal 1314 …… I / O terminal for data communication 1430 …… TV monitor 1440 …… Personal computer

Claims (15)

An organic layer in which a first organic semiconductor layer mainly composed of a first organic semiconductor material and a second organic semiconductor layer mainly composed of a second organic semiconductor material are laminated in this order on a substrate. A method of manufacturing an organic semiconductor element for manufacturing a semiconductor element,
Dissolving the second organic semiconductor material in a first liquid material in which the first organic semiconductor material is dissolved or dispersed in the first liquid and a second liquid that is substantially incompatible with the first liquid. Or a first step of preparing a dispersed second liquid material;
A second step of supplying a first liquid material on the substrate to form a first liquid film;
A third step of forming the second liquid film by supplying the second liquid material on the first liquid film in a state where the first liquid film does not solidify;
By removing the first liquid and the second liquid from the first liquid film and the second liquid film, these films are solidified so that the first organic semiconductor layer and the second liquid are solidified. And a fourth step of forming the organic semiconductor layer in a lump.   2. The method of manufacturing an organic semiconductor element according to claim 1, wherein in the third step, the second liquid material is supplied as droplets onto the first liquid film.   In the fourth step, the first liquid and the second liquid are removed by bringing the flat plate into contact with the second coating, and then the second coating is layered. The manufacturing method of the organic-semiconductor element of Claim 1 or 2 performed in the state which prescribed | regulated the separation distance with the said board | substrate.   The said flat plate is a manufacturing method of the organic-semiconductor element of Claim 3 which has liquid repellency in the surface which contacts the said 2nd liquid material.   In the fourth step, the first liquid and the second liquid are removed by heating and / or depressurizing the first liquid material and the second liquid material. The manufacturing method of the organic-semiconductor element in any one of.   The method of manufacturing an organic semiconductor element according to claim 5, wherein the heating is performed from the second liquid film side.   The method of manufacturing an organic semiconductor element according to claim 1, wherein the first liquid is a polar solvent, and the second liquid is a solvent having a polarity lower than that of the polar solvent.   The method of manufacturing an organic semiconductor element according to claim 7, wherein the first liquid material includes a dispersant that improves dispersibility of the first organic semiconductor material in the first liquid.   The method for manufacturing an organic semiconductor element according to claim 8, wherein a mixing ratio of the first organic semiconductor material and the dispersant in the first liquid material is 10: 1 to 50: 1 by weight.   10. The relationship according to claim 1, wherein when the boiling point of the first liquid is A [° C.] and the boiling point of the second liquid is B [° C.], the absolute value of AB is 75 or less. The manufacturing method of the organic-semiconductor element in any one.   The method of manufacturing an organic semiconductor element according to claim 1, wherein the first organic semiconductor material and the second organic semiconductor material are different from each other. The organic semiconductor element is an organic electroluminescence element,
The method of manufacturing an organic semiconductor element according to claim 11, wherein the first organic semiconductor layer is a hole transport layer, and the second organic semiconductor layer is a light emitting layer.   An organic semiconductor element manufactured by the method for manufacturing an organic semiconductor element according to claim 1.   An organic semiconductor device comprising the organic semiconductor element according to claim 13. An electronic apparatus comprising the organic semiconductor device according to claim 14.

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