JP2011070774A - Film formation method, light-emitting element and light-emitting device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a film forming method with a material layer, containing two or more kinds of film formation materials having different sublimation temperatures, formed on a support substrate by heating treatment on a film-formed substrate, without generating concentration gradient of two or more kinds of film formation material having different sublimation temperatures. <P>SOLUTION: In the film formation method, with one of the surfaces of a first substrate having an absorption layer formed on a surface of the substrate, and a material layer formed on the absorption layer and containing a first film formation material, a second film formation material and a polymer compound satisfies the formula (1): Ta-100≤S≤400 (in the formula, S indicates the glass transition temperature (°C) of the polymer compound, and T<SB>a</SB>indicates a higher temperature (°C) of the sublimation temperatures (°C) of the first and the second film formation materials); and a film-formed surface of a second substrate are arranged mutually facing; and a layer including the first and the second film formation materials is formed on the film-formed surface of the second substrate, by carrying out heat treatment from the other surface side of the first substrate. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

The present invention relates to a film forming method for forming a film on a substrate. Further, the present invention relates to a light-emitting element manufactured by the film formation method. Further, the present invention relates to a light emitting device having the light emitting element.

A light-emitting element using an organic compound having characteristics such as thin and light weight, high-speed response, and direct current low-voltage driving as a light emitter is expected to be applied to a next-generation flat panel display. In particular, a display device in which light emitting elements are arranged in a matrix is considered to be superior to a conventional liquid crystal display device in that it has a wide viewing angle and excellent visibility.

The light-emitting mechanism of a light-emitting element is such that an electron injected from a cathode and a hole injected from an anode are EL by applying a voltage with an electroluminescence (hereinafter also referred to as EL) layer sandwiched between a pair of electrodes. It is said that a molecular exciton is formed by recombination at the emission center of the layer, and when the molecular exciton relaxes to the ground state, it emits energy and emits light. Singlet excitation and triplet excitation are known as excited states, and light emission is considered to be possible through either excited state.

The EL layer included in the light-emitting element has at least a light-emitting layer. In addition, the EL layer can have a stacked structure including a hole injection layer, a hole transport layer, an electron transport layer, an electron injection layer, and the like in addition to the light-emitting layer.

Further, EL materials for forming the EL layer are roughly classified into low molecular (monomer) materials and high molecular (polymer) materials. In general, a low molecular weight material is often formed using a vapor deposition method, and a high molecular weight material is often formed using an ink jet method or a spin coat method.

A vapor deposition apparatus used in the case of the vapor deposition method includes a substrate holder on which a substrate is installed, an EL material, that is, a crucible (or vapor deposition boat) enclosing the vapor deposition material, a heater for heating the EL material in the crucible, and an EL that sublimates A shutter for preventing diffusion of the material, and the EL material heated by the heater is sublimated to form a film on the substrate.

However, in practice, in order to uniformly form a film, it is necessary to rotate the deposition target substrate and to keep the distance between the substrate and the crucible more than a certain value. In addition, when performing painting through a shadow mask such as a metal mask using a plurality of EL materials, the interval between different pixels is designed wide, and the width of the partition made of an insulating material provided between the pixels is widened. It is necessary to do. For this reason, high definition (increase in the number of pixels) of a light emitting device including a light emitting element and miniaturization of each display pixel pitch accompanying downsizing are major issues. At the same time, it is required to improve productivity and reduce costs.

On the other hand, a method of forming an EL layer of a light emitting element by thermal transfer has been proposed (see Patent Document 1). Patent Document 1 describes an evaporation source substrate having a material layer composed of a mixture of an evaporation material and a binder material. By heat-treating such a deposition source substrate, a deposition material layer can be formed on the deposition target substrate.

JP 2008-291352 A

When a thermal transfer of a material layer containing two or more types of film forming materials having different sublimation temperatures is performed using a light source such as a halogen lamp or a flash lamp or a heat source such as a heater, the heating time by the light source or the heat source is long. A material having a higher sublimation temperature is transferred after a low material is transferred first, and is then formed on a film formation substrate. Therefore, many materials with a low sublimation temperature are contained in the vapor deposition material layer on the deposition target substrate, and many materials with a high sublimation temperature are contained in the surface portion of the vapor deposition material layer. That is, a plurality of film forming materials are not uniformly dispersed in the vapor deposition material layer, and a concentration gradient is generated.

As described above, when a vapor deposition material layer having a concentration gradient is formed on a deposition target substrate due to a difference in sublimation temperature, there is a risk of adversely affecting the characteristics of the light-emitting element such as a luminescent color.

Thus, according to one embodiment of the present invention, in a method for forming a material layer including two or more film formation materials having different sublimation temperatures formed over a supporting substrate over a film formation substrate by heat treatment, the sublimation temperatures are different. One of the problems is that two or more kinds of film forming materials are formed without causing a concentration gradient. Another object of one embodiment of the present invention is to provide a light-emitting element manufactured using the film formation method. Another object of one embodiment of the present invention is to provide a light-emitting device including the light-emitting element.

The above object includes at least an absorption layer and a material layer, and the material layer includes at least a first film formation material, a second film formation material, and a polymer compound satisfying the following mathematical formula (1). The first film-forming material and the second film-forming material contained in the heated material layer are covered by heat treatment from the other surface side of the film-forming substrate on which the material layer is formed. This can be solved by a film formation method in which an EL layer is formed over a film formation substrate.

(In the formula (1), S represents the glass transition temperature of the polymer compound (℃), T _a is a temperature higher among sublimation temperature (℃) of the first film-forming material or the second film-forming material (Centigrade)

According to one embodiment of the present invention, an absorption layer formed over one surface of a substrate, and a high film that is formed over the absorption layer and satisfies the first deposition material, the second deposition material, and the above formula (1). One surface of the first substrate having a material layer containing a molecular compound and the deposition surface of the second substrate are arranged to face each other, and the material layer is heated from the other surface side of the first substrate. In this film formation method, a layer including the first film formation material and the second film formation material is formed on the film formation surface of the second substrate by performing the treatment.

Another embodiment of the present invention is a deposition method in which the absorption layer is formed in an island shape or a stripe shape in the above structure.

Another embodiment of the present invention is a deposition method in which the material layer is formed in an island shape or a stripe shape in the above structure.

Another embodiment of the present invention is a film formation method in which a reflective layer having an opening is formed between the first substrate and the absorption layer in the above structure.

Another embodiment of the present invention is a film formation method in which, in the above structure, a heat insulating layer having an opening in a position overlapping with the opening of the reflective layer is formed between the reflective layer and the absorption layer.

Another embodiment of the present invention is a deposition method in which a protective layer is formed between an absorption layer and a material layer in the above structure.

Another embodiment of the present invention is a film formation method using a cycloolefin polymer as the polymer compound in the above structure.

Another embodiment of the present invention is the above structure, in which the material layer is formed by a vapor deposition method, a sputtering method, a spin coating method, a printing method, a droplet discharge method, a spray method, a dropping method, an ink jet method, a nozzle printing method, or a dispensing method. Is a film forming method formed on the absorption layer.

Further, according to one embodiment of the present invention, in the above structure, the heat treatment is performed by irradiating light from the other surface side of the first substrate using a light source and heating the absorption layer by absorbing light. This is a film forming method to be used.

Another embodiment of the present invention is a film formation method using the laser oscillator, the flash lamp, or the halogen lamp as a light source in the above structure.

Another embodiment of the present invention is a light-emitting element manufactured using the film formation method having the above structure. In addition, a light-emitting device including the light-emitting element of one embodiment of the present invention is also included in the present invention.

According to one embodiment of the present invention, two or more kinds of film formation materials having different sublimation temperatures can be formed even when a material layer including two or more kinds of film formation materials having different sublimation temperatures is formed on the deposition target substrate by heat treatment. Can be formed without causing a concentration gradient. Further, according to one embodiment of the present invention, a light-emitting element having stable characteristics such as a light-emitting color can be provided using the film formation method. One embodiment of the present invention can provide a highly reliable light-emitting device including the light-emitting element.

4A and 4B illustrate a film formation method of one embodiment of the present invention. 4A and 4B illustrate a film formation method of one embodiment of the present invention. 4A and 4B illustrate a film formation method of one embodiment of the present invention. FIG. 9 illustrates an example of a light-emitting element. FIG. 11 illustrates an example of a passive matrix light-emitting device. FIG. 11 illustrates an example of a passive matrix light-emitting device. FIG. 11 illustrates an example of an active matrix light-emitting device. FIG. 14 illustrates an example of an electronic device. The figure which shows a photoluminescence spectrum. The figure which shows the result of ToF-SIMS. The figure which shows the result of ToF-SIMS. The figure which shows the result of ToF-SIMS. The figure which shows a photoluminescence spectrum. The figure which shows a photoluminescence spectrum. The figure which shows a photoluminescence spectrum. The figure which shows a photoluminescence spectrum.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. However, the present invention is not limited to the following description, and it will be easily understood by those skilled in the art that modes and details can be variously changed without departing from the spirit and scope of the present invention. Therefore, the present invention should not be construed as being limited to the description of the embodiments below.

(Embodiment 1)
In this embodiment, a film formation method of one embodiment of the present invention will be described. Note that in this embodiment, the case where an EL layer of a light-emitting element is formed using the film formation method of one embodiment of the present invention will be described. In this embodiment, a case where heat treatment is performed using a light source will be described. 1A is a perspective view illustrating a film formation substrate of one embodiment of the present invention, and FIGS. 1B and 1C are perspective views illustrating a concept of a film formation method of one embodiment of the present invention. FIG.

In FIG. 1A, an absorption layer 103 is formed on one surface of a first substrate 101 which is a support substrate. In addition, a first material layer 105 including a first film formation material 105 a, a second film formation material 105 b, and a polymer compound 105 c is formed over the absorption layer 103.

A method for manufacturing the deposition substrate illustrated in FIG. 1A will be described.

First, the absorption layer 103 is formed on one surface of the first substrate 101. The first substrate 101 is a support substrate such as an absorption layer or a material layer, and is a substrate that transmits light used for forming the material layer on the deposition target substrate. Therefore, the first substrate 101 is preferably a substrate with high light transmittance. Specifically, when lamp light or laser light is used to form the second material layer, it is preferable to use a substrate that transmits the light as the first substrate 101. As the first substrate 101, for example, a glass substrate, a quartz substrate, a plastic substrate containing an inorganic material, or the like can be used.

The absorption layer 103 is a layer that absorbs light irradiated to heat the first material layer 105 and converts it into heat. The absorption layer 103 is preferably formed of a material having a low reflectance of 70% or less with respect to the irradiated light and a high absorption rate. Moreover, it is preferable that the absorption layer 103 is formed of a material having excellent heat resistance so that the absorption layer 103 does not change by heat. As a material that can be used for the absorption layer 103, for example, metal nitride such as titanium nitride, tantalum nitride, molybdenum nitride, tungsten nitride, chromium nitride, or manganese nitride, molybdenum, titanium, tungsten, or carbon can be used. preferable.

The absorption layer 103 can be formed using various methods. For example, the absorption layer 103 can be formed by a sputtering method using a target such as molybdenum, tantalum, titanium, or tungsten, or a target using an alloy thereof. The absorbing layer 103 is not limited to a single layer, and may be composed of a plurality of layers.

The thickness of the absorption layer 103 is preferably a thickness that does not transmit irradiated light. Although it varies depending on the material, the film thickness is preferably 100 nm or more and 2 μm or less. In particular, by setting the thickness of the absorption layer 103 to 100 nm or more and 600 nm or less, it is possible to efficiently absorb irradiated light and generate heat.

Note that when the first film formation material 105a and the second film formation material 105b included in the first material layer 105 are heated to the sublimation temperature, the absorption layer 103 transmits part of the light to be irradiated. You may do it. However, in the case where part of the light is transmitted, a material that does not decompose even when irradiated with light is preferably used for the first material layer 105.

Next, the first material layer 105 including at least the first film formation material 105 a, the second film formation material 105 b, and the polymer compound 105 c is formed over the absorption layer 103. The first material layer 105 is a layer formed including a first film-forming material 105 a and a second film-forming material 105 b which are formed over a deposition target substrate. In this embodiment mode, two kinds of the first film formation material 105 a and the second film formation material 105 b are used for the first material layer 105, but three or more kinds of film formation materials are used as the first material layer 105. It can also be used. Further, the first material layer 105 may be a single layer or a plurality of layers may be stacked.

The first material layer 105 is formed by various methods. For example, a wet coating method such as spin coating, spray coating, ink jet, dip coating, casting, die coating, roll coating, blade coating, bar coating, gravure coating, nozzle printing or printing Can be used. Alternatively, a dry method such as a vacuum evaporation method or a sputtering method can be used.

In the case where the first material layer 105 is formed by a wet method, a desired first film-forming material, second film-forming material, and polymer compound are dissolved or dispersed in a solvent, and the solution or the dispersion liquid is Adjust it. The solvent can dissolve or disperse the first film forming material, the second film forming material, and the polymer compound, and does not react with the first film forming material, the second film forming material, and the polymer compound. If it is a thing, it will not specifically limit. For example, halogen solvents such as chloroform, tetrachloromethane, dichloromethane, 1,2-dichloroethane, or chlorobenzene, ketone solvents such as acetone, methyl ethyl ketone, diethyl ketone, n-propyl methyl ketone, or cyclohexanone, benzene, toluene, or Aromatic solvents such as xylene, ethyl acetate, n-propyl acetate, n-butyl acetate, ethyl propionate, γ-butyrolactone, ester solvents such as diethyl carbonate, ether solvents such as tetrahydrofuran or dioxane, dimethylformamide Alternatively, an amide solvent such as dimethylacetamide, dimethyl sulfoxide, hexane, water, or the like can be used. Moreover, you may mix and use multiple types of these solvents. By using the wet method, the utilization efficiency of the material can be increased, and the manufacturing cost can be reduced.

Note that the thickness of the second material layer 109 formed over the second substrate 107 which is a deposition target substrate in a later step is the same as that of the first material formed over the first substrate which is a supporting substrate. Depends on layer 105. Therefore, by controlling the thickness of the first material layer, the thickness of the second material layer 109 formed over the second substrate 107 which is a deposition target substrate can be easily controlled. Note that the first material layer 105 is not necessarily a uniform layer as long as the thickness and uniformity of the second material layer are maintained. For example, it may be formed in a fine island shape, or may be formed in a layered structure.

In this embodiment, in order to form the EL layer of the light-emitting element over the deposition target substrate, a light-emitting substance is used as the first film-formation material 105 a included in the first material layer 105, and the second layer As the film formation material 105b, an organic compound in which a light-emitting substance is dispersed is used.

As the light-emitting substance, for example, a fluorescent compound that emits fluorescence or a phosphorescent compound that emits phosphorescence can be used.

As the light-emitting substance, the following phosphorescent compounds can be used. Bis [2- (4 ′, 6′-difluorophenyl) pyridinato-N, C ^{2 ′} ] iridium (III) tetrakis (1-pyrazolyl) borate (abbreviation: FIr6), bis [2- (4 ′, 6′- Difluorophenyl) pyridinato-N, C ^{2 ′} ] iridium (III) picolinate (abbreviation: FIrpic), bis [2- (3 ′, 5′-bistrifluoromethylphenyl) pyridinato-N, C ^{2 ′} ] iridium (III) Picolinate (abbreviation: Ir (CF ₃ ppy) ₂ (pic)), bis [2- (4 ′, 6′-difluorophenyl) pyridinato-N, C ^{2 ′} ] iridium (III) acetylacetonate (abbreviation: FIracac) , tris (2-phenylpyridinato) iridium (III) (abbreviation: Ir _(ppy) 3), bis (2-phenylpyridinato-) Ili Um (III) acetylacetonate _{(abbreviation: Ir (ppy) 2 (acac} )), bis (benzo [h] quinolinato) iridium (III) acetylacetonate _{(abbreviation: Ir (bzq) 2 (acac} )), bis ( 2,4-diphenyl-1,3-oxazolate-N, C ^{2 ′} ) iridium (III) acetylacetonate (abbreviation: Ir (dpo) ₂ (acac)), bis [2- (4′-perfluorophenylphenyl) ) Pyridinato] iridium (III) acetylacetonate (abbreviation: Ir (p-PF-ph) ₂ (acac)), bis (2-phenylbenzothiazolate-N, C ^{2 ′} ) iridium (III) acetylacetonate _{(abbreviation: Ir (bt) 2 (acac} )), bis [2- (2'-benzo [4, 5-alpha] thienyl) pyridinato -N, ^{3 ']} iridium (III) acetylacetonate _{(abbreviation: Ir (btp) 2 (acac} )), bis (1-phenylisoquinolinato--N, C ^2') iridium (III) acetylacetonate (abbreviation: Ir ( piq) ₂ (acac)), (acetylacetonato) bis [2,3-bis (4-fluorophenyl) quinoxalinato] iridium (III) (abbreviation: Ir (Fdpq) ₂ (acac)), (acetylacetonato) Bis (2,3,5-triphenylpyrazinato) iridium (III) (abbreviation: Ir (tppr) ₂ (acac)), 2,3,7,8,12,13,17,18-octaethyl-21H , 23H-porphyrin platinum (II) (abbreviation: PtOEP), tris (acetylacetonato) (monophenanthroline) terbium ( III) (abbreviation: Tb (acac) ₃ (Phen)), tris (1,3-diphenyl-1,3-propanedionate) (monophenanthroline) europium (III) (abbreviation: Eu (DBM) ₃ (Phen) ), Tris [1- (2-thenoyl) -3,3,3-trifluoroacetonato] (monophenanthroline) europium (III) (abbreviation: Eu (TTA) ₃ (Phen)), and the like.

Further, as the luminescent substance, the following fluorescent compounds can be used. For example, N, N′-bis [4- (9H-carbazol-9-yl) phenyl] -N, N′-diphenylstilbene-4,4′-diamine (abbreviation: YGA2S), 4- (9H-carbazole- 9-yl) -4 '-(10-phenyl-9-anthryl) triphenylamine (abbreviation: YGAPA), 4- (9H-carbazol-9-yl) -4'-(9,10-diphenyl-2- Anthryl) triphenylamine (abbreviation: 2YGAPPA), N, 9-diphenyl-N- [4- (10-phenyl-9-anthryl) phenyl] -9H-carbazol-3-amine (abbreviation: PCAPA), perylene, 2 , 5,8,11-tetra-tert-butylperylene (abbreviation: TBP), 4- (10-phenyl-9-anthryl) -4 '-(9-phenyl-9H-ca Basol-3-yl) triphenylamine (abbreviation: PCBAPA), N, N ″-(2-tert-butylanthracene-9,10-diyldi-4,1-phenylene) bis [N, N ′, N ′ -Triphenyl-1,4-phenylenediamine] (abbreviation: DPABPA), N, 9-diphenyl-N- [4- (9,10-diphenyl-2-anthryl) phenyl] -9H-carbazol-3-amine ( Abbreviation: 2PCAPPA), N- [4- (9,10-diphenyl-2-anthryl) phenyl] -N, N ′, N′-triphenyl-1,4-phenylenediamine (abbreviation: 2DPAPPA), N, N , N ′, N ′, N ″, N ″, N ′ ″, N ′ ″-octaphenyldibenzo [g, p] chrysene-2,7,10,15-tetraamine (abbreviation: DBC) ), Coumarin 30,9,10-diphenyl-2- [N-phenyl-N- (9-phenyl-9H-carbazol-3-yl) amino] anthracene (abbreviation: 2PCAPA), N- [9,10-bis (1,1′-biphenyl-2-yl) -2-anthryl] -N, 9-diphenyl-9H-carbazol-3-amine (abbreviation: 2PCABPhA), N- (9,10-diphenyl-2-anthryl) -N, N ', N'-triphenyl-1,4-phenylenediamine (abbreviation: 2DPAPA), N- [9,10-bis (1,1'-biphenyl-2-yl) -2-anthryl]- N, N ′, N′-triphenyl-1,4-phenylenediamine (abbreviation: 2DPABPhA), 9,10-bis (1,1′-biphenyl-2-yl) -N- [4- (9H-carbazo -9-yl) phenyl] -N-phenylanthracen-2-amine (abbreviation: 2YGABPhA), N, N, 9-triphenylanthracen-9-amine (abbreviation: DPhAPhA) coumarin 545T, N, N'- Diphenylquinacridone, (abbreviation: DPQd), rubrene, 5,12-bis (1,1′-biphenyl-4-yl) -6,11-diphenyltetracene (abbreviation: BPT), 2- (2- {2- [ 4- (dimethylamino) phenyl] ethenyl} -6-methyl-4H-pyran-4-ylidene) propanedinitrile (abbreviation: DCM1), 2- {2-methyl-6- [2- (2,3,6) , 7-Tetrahydro-1H, 5H-benzo [ij] quinolizin-9-yl) ethenyl] -4H-pyran-4-ylidene} propanedinitrile (abbreviation: DCM2 N, N, N ′, N′-tetrakis (4-methylphenyl) tetracene-5,11-diamine (abbreviation: p-mPhTD), 7,13-diphenyl-N, N, N ′, N′-tetrakis (4-Methylphenyl) acenaphtho [1,2-a] fluoranthene-3,10-diamine (abbreviation: p-mPhAFD), 2- {2-isopropyl-6- [2- (1,1,7,7- Tetramethyl-2,3,6,7-tetrahydro-1H, 5H-benzo [ij] quinolizin-9-yl) ethenyl] -4H-pyran-4-ylidene} propanedinitrile (abbreviation: DCJTI), 2- { 2-tert-butyl-6- [2- (1,1,7,7-tetramethyl-2,3,6,7-tetrahydro-1H, 5H-benzo [ij] quinolizin-9-yl) ethenyl]- 4H-Pyra -4-ylidene} propanedinitrile (abbreviation: DCJTB), 2- (2,6-bis {2- [4- (dimethylamino) phenyl] ethenyl} -4H-pyran-4-ylidene) propanedinitrile (abbreviation) : BisDCM), 2- {2,6-bis [2- (8-methoxy-1,1,7,7-tetramethyl-2,3,6,7-tetrahydro-1H, 5H-benzo [ij] quinolidine -9-yl) ethenyl] -4H-pyran-4-ylidene} propanedinitrile (abbreviation: BisDCJTM).

As the organic compound that disperses the light-emitting substance, when the light-emitting substance is a fluorescent compound, a substance having a singlet excitation energy (energy difference between the ground state and the singlet excited state) larger than that of the fluorescent compound is used. preferable. In the case where the light-emitting substance is a phosphorescent compound, a substance having a triplet excitation energy (energy difference between a ground state and a triplet excited state) larger than that of the phosphorescent compound is preferably used.

Examples of the organic compound in which the light-emitting substance is dispersed include tris (8-quinolinolato) aluminum (III) (abbreviation: Alq), tris (4-methyl-8-quinolinolato) aluminum (III) (abbreviation: Almq ₃ ), bis ( 10-hydroxybenzo [h] quinolinato) beryllium (II) (abbreviation: BeBq ₂ ), bis (2-methyl-8-quinolinolato) (4-phenylphenolato) aluminum (III) (abbreviation: BAlq), bis (8 -Quinolinolato) zinc (II) (abbreviation: Znq), bis [2- (2-benzoxazolyl) phenolato] zinc (II) (abbreviation: ZnPBO), bis [2- (2-benzothiazolyl) phenolato] zinc ( II) Metal complexes such as (abbreviation: ZnBTZ), 2- (4-biphenylyl) -5- (4-tert-butyl) Phenyl) -1,3,4-oxadiazole (abbreviation: PBD), 1,3-bis [5- (p-tert-butylphenyl) -1,3,4-oxadiazol-2-yl] benzene (Abbreviation: OXD-7), 3- (4-biphenylyl) -4-phenyl-5- (4-tert-butylphenyl) -1,2,4-triazole (abbreviation: TAZ), 2,2 ′, 2 ''-(1,3,5-benzenetriyl) tris (1-phenyl-1H-benzimidazole) (abbreviation: TPBI), bathophenanthroline (abbreviation: BPhen), bathocuproin (abbreviation: BCP), 9- [4 Heterocyclic compounds such as-(5-phenyl-1,3,4-oxadiazol-2-yl) phenyl] -9H-carbazole (abbreviation: CO11), 4,4'-bis [N- (1-naphthyl) ) -N-F Nenylamino] biphenyl (NPB), N, N′-bis (3-methylphenyl) -N, N′-diphenyl- [1,1′-biphenyl] -4,4′-diamine (abbreviation: TPD), 4, An aromatic amine compound such as 4′-bis [N- (spiro-9,9′-bifluoren-2-yl) -N-phenylamino] biphenyl (abbreviation: BSPB) can be given. In addition, condensed polycyclic aromatic compounds such as anthracene derivatives, phenanthrene derivatives, pyrene derivatives, chrysene derivatives, and dibenzo [g, p] chrysene derivatives can be given. Specifically, 9,10-diphenylanthracene (abbreviation: DPAnth) N, N-diphenyl-9- [4- (10-phenyl-9-anthryl) phenyl] -9H-carbazol-3-amine (abbreviation: CzA1PA), 4- (10-phenyl-9-anthryl) triphenyl Amine (abbreviation: DPhPA), 4- (9H-carbazol-9-yl) -4 ′-(10-phenyl-9-anthryl) triphenylamine (abbreviation: YGAPA), N, 9-diphenyl-N- [4 -(10-phenyl-9-anthryl) phenyl] -9H-carbazol-3-amine (abbreviation: PCAPA), N, 9-diphenyl-N- {4- [4- (10-phenyl-9-anthryl) phenyl] phenyl} -9H-carbazol-3-amine (abbreviation: PCAPBA), 9,10-diphenyl-2- [ N-phenyl-N- (9-phenyl-9H-carbazol-3-yl) amino] anthracene (abbreviation: 2PCAPA), 6,12-dimethoxy-5,11-diphenylchrysene, N, N, N ′, N ′ , N ″, N ″, N ′ ″, N ′ ″-octaphenyldibenzo [g, p] chrysene-2,7,10,15-tetraamine (abbreviation: DBC1), 9- [4- ( N-carbazolyl) phenyl] -10-phenylanthracene (abbreviation: CzPA), 3,6-diphenyl-9- [4- (10-phenyl-9-anthryl) phenyl] -9H-carbazole (abbreviation: DPCz) A), 9,10-bis (3,5-diphenylphenyl) anthracene (abbreviation: DPPA), 9,10-di (2-naphthyl) anthracene (abbreviation: DNA), 2-tert-butyl-9,10- Di (2-naphthyl) anthracene (abbreviation: t-BuDNA), 9,9′-bianthryl (abbreviation: BANT), 9,9 ′-(stilbene-3,3′-diyl) diphenanthrene (abbreviation: DPNS), 9,9 ′-(stilbene-4,4′-diyl) diphenanthrene (abbreviation: DPNS2), 3,3 ′, 3 ″-(benzene-1,3,5-triyl) tripylene (abbreviation: TPB3), etc. Can be mentioned.

Note that as a film formation material included in the first material layer 105, two or more kinds of organic compounds in which a light-emitting substance is dispersed may be used, or two or more kinds of light-emitting substances dispersed in an organic compound may be used. Further, an organic compound in which two or more kinds of luminescent substances are dispersed and two or more kinds of luminescent substances may be used.

As the high molecular compound 105c included in the first material layer 105, a high molecular compound having a glass transition temperature satisfying the following mathematical formula (1) is used. More preferably, a polymer compound having a glass transition temperature satisfying the following mathematical formula (2) is used. Note that in the following formulas (1) and (2), the sublimation temperatures of the first film-forming material and the second film-forming material are measured at the same degree of vacuum (for example, a degree of vacuum of 10 ⁻³ Pa).

(In the formula (1) (2), S represents the glass transition temperature (℃) of the polymer compound, T _a, of the first film forming material or the second sublimation temperature of the film forming material (℃) High temperature (℃))

If the glass transition temperature of the polymer compound is in the range satisfying the above formula (1), preferably the above formula (2), the temperature reaches the lower one of the sublimation temperatures of the first film forming material or the second film forming material. However, the film-forming material that has reached the sublimation temperature is hardly transferred from the first material layer. This is because the high molecular compound suppresses the movement of the first film-forming material and the second film-forming material in the first material layer. When the temperature of the first film formation material or the second film formation material exceeds a high temperature, the first film formation material and the second film formation material move in the first material layer. Is easily transferred onto the film formation substrate. Accordingly, there is little time difference between the transfer of the first film formation material and the transfer of the second film formation material, and an EL layer with a small concentration gradient can be formed over the deposition target substrate.

However, when the glass transition temperature of the polymer compound is lower than the range of the above mathematical formula (1), the first film-forming material and the second film-forming material are hardly suppressed from moving in the first material layer. When the temperature reaches the lower sublimation temperature of the first film forming material or the second film forming material, the film forming material having the lower sublimation temperature is transferred first, and then the film forming material having the higher sublimation temperature is transferred. The Further, if the glass transition temperature of the polymer compound is higher than the range of the mathematical formula (1), the first film-forming material and the second film-forming material after the first sublimation temperature exceeds a high temperature, The film-forming material and the second film-forming material are prevented from moving in the first material layer, and transfer is not easily performed.

Therefore, as the polymer compound 105c, a polymer compound having a glass transition temperature that satisfies the above formula (1), preferably the above formula (2) is used. Note that in this embodiment mode, transfer means that the first film formation material or the second film formation material included in the first material layer is transferred onto the deposition target substrate.

The polymer compound 105c included in the first material layer 105 is preferably a cycloolefin polymer. Since the cycloolefin polymer is easily dissolved in a solvent, after the film is formed on the deposition target substrate, the cycloolefin polymer containing the first film-forming material and the second film-forming material remaining on the film-forming substrate is reused in the solvent. By dissolving, the deposition substrate can be reused. Therefore, the consumption and cost of the material can be suppressed. Further, as the polymer compound, olefin, vinyl, acrylic, polyimide (PI), or the like may be used, or a polymer material EL material may be used. Examples of the polymer material EL material include poly (N-vinylcarbazole) (PVK) and poly (p-phenylene vinylene) (PPV). In addition, a cross-linked polymer such as an epoxy resin, an acrylic resin, or siloxane may be used. In the present specification, a polymer compound means a polymer (polymer) having a repeating structure of one or more kinds of monomers.

Since the viscosity of the polymer compound can be easily adjusted, the viscosity of the polymer compound solution can be freely adjusted according to the application. For example, when the first material layer 105 is formed by a droplet discharge method, by increasing the viscosity of the polymer compound solution, the polymer compound does not spread on the deposition surface, and a fine pattern is formed. can do.

Adjustment of the viscosity of the polymer compound solution can be achieved by adjusting the molecular weight of the polymer compound or changing the ratio of the polymer compound and the solvent. In general, as the ratio of the polymer compound increases, the viscosity of the solution increases.

Further, although the case where the absorption layer 103 and the first material layer 105 are formed over the entire surface of the first substrate 101 has been described in this embodiment, the absorption layer 103 and the first material layer 105 are selectively formed. May be.

Note that in this embodiment, a supporting substrate having an area similar to that of a deposition target substrate on which a material layer including a first deposition material, a second deposition material, and a polymer compound is formed is used. However, this embodiment is not limited to this, and may not be a supporting substrate having the same area as the deposition target substrate.

Next, as illustrated in FIG. 1B, the second substrate which is a deposition target substrate is positioned at a position facing the surface on which the absorption layer 103 and the first material layer 105 are formed in the first substrate 101. A substrate 107 is disposed. The second substrate 107 is a deposition target substrate on which a desired layer is formed by heat treatment. The second substrate 107 is not limited to a specific one as long as it has necessary heat resistance and has an insulating surface. For example, a glass substrate, a quartz substrate, a stainless steel substrate on which an insulating film is formed, and the like can be given. Alternatively, a plastic substrate having heat resistance enough to withstand heat treatment may be used.

Note that although not illustrated in FIG. 1, here, the case where an EL layer of a light-emitting element is formed using the deposition substrate of one embodiment of the present invention, a light-emitting element is formed over the second substrate 107. A first electrode layer which serves as one electrode of the element is included. The end of the first electrode layer is preferably covered with an insulator. In this embodiment mode, the first electrode layer indicates an electrode which serves as an anode or a cathode of the light emitting element.

The surface of the first material layer 105 and the surface of the second substrate 107 are arranged with an interval of a distance d. Here, the distance d is 0 mm to 2 mm, preferably 0 mm to 0.05 mm, and more preferably 0 mm to 0.03 mm. By reducing the distance d to about the above range, the utilization efficiency of the first film-forming material and the second film-forming material can be improved. In this embodiment mode, the distance between the deposition substrate and the deposition target substrate is narrowed (in order to reduce the distance d) in order to improve the material utilization efficiency. The form is not limited to this.

Note that the distance d is a distance between the surface of the first material layer containing the first film formation material, the second film formation material, and the polymer compound on the first substrate and the surface of the second substrate. It shall be defined in However, when some film (for example, a conductive film or a partition wall functioning as an electrode) is formed on the second substrate and the second substrate surface has irregularities, the distance d is equal to the first distance on the first substrate. It is defined by the distance between the surface of the material layer and the outermost surface of the layer formed on the second substrate, that is, the surface of these films (conductive film or partition wall).

Further, although the case where the number of deposition target substrates is one is described in this embodiment mode, a plurality of deposition target substrates may be arranged side by side so as to face the deposition target substrate. In this case, the areas of the plurality of deposition target substrates and the deposition substrate are set to be approximately the same. By providing a plurality of deposition substrates with respect to the deposition substrate, a plurality of deposition substrates can be processed at the same time.

The surface of the first material layer 105 and the deposition surface of the second substrate 107 are preferably arranged so as to be parallel to each other.

The first substrate 101 and the second substrate 107 only need to face each other, and the angle of these substrates with respect to the horizontal plane is not particularly limited. That is, a film formation apparatus used in one embodiment of the present invention may be a face-down method, a face-up method, or a vertical substrate method.

Then, as shown in FIG. 1C, heat treatment is performed from the back surface of the first substrate 101, that is, the other surface side of the first substrate 101 on which the first material layer 105 is formed. The first film formation material 105 a and the second film formation material 105 b in the one material layer 105 are formed over the second substrate 107. Thus, a second material layer 109 that is an EL layer of the light-emitting element is formed over the second substrate 107. The heat treatment is performed so that the entire surface of the first substrate 101 is heated. Note that the second material layer 109 is formed thinner than the thickness of the first material layer 105. In addition, a decomposition product of the polymer compound 105 c may be mixed in the second material layer 109. Therefore, the high molecular compound 105c included in the second material layer 109 is preferably a material in which a decomposition product does not affect the characteristics of the EL layer.

In this embodiment mode, the temperature of the heat treatment exceeds the sublimation temperatures of the first film formation material and the second film formation material and is 50% higher than the sublimation temperatures of the first film formation material and the second film formation material. It is preferable to set it high within a range not exceeding ° C. Further, depending on the distance between the first substrate and the second substrate, or the material and thickness of the second substrate which is the film formation substrate, in order to reduce the influence of the radiant heat of the heat source, the above temperature range may be satisfied. It may be set lower. Here, the temperature of the heat treatment is measured on the surface of the first substrate.

In addition, it is preferable to perform the heat treatment so that the temperature becomes equal to or higher than the highest sublimation temperature among the sublimation temperatures of the first film formation material and the second film formation material. In this case, it is preferable to set the temperature higher than the sublimation temperature of the film forming material having the highest sublimation temperature and up to 50 ° C., but the decomposition temperature of the substance having the lower sublimation temperature, In consideration of the distance and the material and thickness of the film formation substrate, the temperature may be set to a lower temperature within the above temperature range (however, the sublimation temperature of the substance having the highest sublimation temperature).

The heat treatment is preferably performed by a method of irradiating the first substrate 101 with light using a lamp or a laser oscillation device. The lamp and the laser oscillation device may be installed so that the back surface of the first substrate 101 can be irradiated with light. Here, the back surface of the first substrate 101 is a surface facing the surface on which the material layer is formed.

As the lamp, a flash lamp (xenon flash lamp, krypton flash lamp, etc.), a xenon lamp, a discharge lamp typified by a metal halide lamp, a heating lamp typified by a halogen lamp, or a tungsten lamp can be used. Since the flash lamp can repeatedly irradiate a large area with a very high intensity light in a short time (0.1 milliseconds to 10 milliseconds), it is efficient regardless of the area of the first substrate 101. It can be heated uniformly. In addition, heating of the first substrate 101 can be controlled by changing a time interval of light emission. Moreover, since the flash lamp has a long life and low power consumption during light emission standby, the running cost can be kept low. Moreover, rapid heating is facilitated by using a flash lamp, and the vertical mechanism and shutter when using a heater can be simplified. Therefore, the film forming apparatus can be further downsized. However, a mechanism in which the flash lamp can be moved up and down so that the heating temperature can be adjusted according to the material of the first substrate 101 may be employed.

A laser oscillation device may be used as a light source other than the lamp. As the laser light, gas laser such as Ar laser, Kr laser, excimer laser, single crystal YAG, YVO ₄ , forsterite (Mg ₂ SiO ₄ ), YAlO ₃ , GdVO ₄ , or polycrystalline (ceramic) YAG, A laser using a medium in which one or more of Nd, Yb, Cr, Ti, Ho, Er, Tm, and Ta are added as dopants to Y ₂ O ₃ , YVO ₄ , YAlO ₃ , and GdVO ₄ , A glass laser, a ruby laser, an alexandrite laser, a Ti: sapphire laser, a copper vapor laser, or a gold vapor laser that is oscillated from one or a plurality of types can be used. In addition, when a solid-state laser whose laser medium is solid is used, there are advantages that a maintenance-free state can be maintained for a long time and output is relatively stable.

In addition, film formation by light irradiation is preferably performed in a reduced pressure atmosphere. Therefore, it is preferable that the film forming chamber has an atmosphere of 5 × 10 ⁻³ Pa or less, preferably 10 ⁻⁴ Pa or less. Note that although heat treatment is performed using a light source in this embodiment mode, heat treatment may be performed using a heat source such as a heater.

As described above, since the film formation method described in this embodiment includes the high molecular compound that satisfies the formula (1), preferably the formula (2), in the first material layer, the first film formation is performed. Even when the temperature of the sublimation temperature of the material or the second film-forming material reaches a low temperature, the film-forming material that has reached the sublimation temperature is not easily transferred from the first material layer. When the temperature of the first film formation material or the second film formation material exceeds a high temperature, the first film formation material and the second film formation material move in the first material layer. Is easily transferred onto the film formation substrate. Accordingly, there is little time difference between the transfer of the first film formation material and the transfer of the second film formation material, and an EL layer with a small concentration gradient can be formed over the deposition target substrate.

Note that this embodiment can be freely combined with any of the other embodiments.

(Embodiment 2)
In this embodiment, a film formation method of one embodiment of the present invention will be described. Note that in this embodiment, the case where an EL layer of a light-emitting element is formed using the film formation method of one embodiment of the present invention will be described. Note that the film formation method described in this embodiment is performed using the same material and manufacturing method as those in the above embodiment, unless otherwise specified.

FIG. 2 shows an example in which a reflective layer, a heat insulating layer, and a protective layer are formed on the first substrate. In FIG. 2A, a reflective layer 302 is selectively formed on one surface of a first substrate 301 which is a support substrate. Note that the reflective layer 302 has an opening 312. In addition, a heat insulating layer 304 is formed on the reflective layer 302. Note that the heat insulating layer 304 has an opening 312 in a position overlapping with the opening of the reflective layer 302. In addition, an absorption layer 303 covering the opening is formed over the first substrate 301 over which the reflective layer 302 and the heat insulating layer 304 are formed. A protective layer 306 is formed over the absorption layer 303. In addition, a first material layer 305 including a first film formation material, a second film formation material, and a polymer compound is formed over the protective layer 306.

Note that in this specification, “overlap” means not only a case where elements (for example, a reflective layer and an absorption layer) constituting a film formation substrate are in direct contact with each other but also an overlapping layer. Including the case of overlapping.

A method for manufacturing the deposition substrate illustrated in FIG. 2A will be described below.

First, the reflective layer 302 is selectively formed on one surface of the first substrate 301. The reflective layer 302 is a layer that reflects light applied to the first substrate 301 and blocks the first material layer 305 formed in a region overlapping with the reflective layer 302 so as not to apply heat. Therefore, the reflective layer 302 is preferably formed using a material having a high reflectivity with respect to light to be irradiated. Specifically, the reflective layer 302 is preferably formed of a material having a high reflectivity of 85% or more, more preferably 90% or more, with respect to the irradiated light. .

As a material that can be used for the reflective layer 302, for example, aluminum, silver, gold, platinum, copper, an alloy containing aluminum (eg, an aluminum-titanium alloy, an aluminum-neodymium alloy, an aluminum-titanium alloy), or silver can be used. An alloy (silver-neodymium alloy) or the like can be used.

Note that the reflective layer 302 can be formed by various methods. For example, it can be formed by sputtering, electron beam vapor deposition, vacuum vapor deposition, or the like. Moreover, although the film thickness of the reflective layer 302 changes with materials, it is preferable to set it as 100 nm or more. By setting the film thickness to 100 nm or more, the irradiated light can be prevented from passing through the reflective layer 302.

Note that the type of material suitable for the reflective layer 302 varies depending on the wavelength of light with which the first substrate 301 is irradiated. The reflective layer is not limited to a single layer, and may be composed of a plurality of layers. Alternatively, the absorption layer 303 may be formed directly over the first substrate 301 without providing a reflective layer.

Note that the greater the difference in reflectance between the reflective layer 302 and the absorbing layer 303, the better. Specifically, the difference in reflectance with respect to the wavelength of light to be irradiated is preferably 25% or more, more preferably 30% or more.

Various methods can be used to form the opening in the reflective layer 302, but dry etching is preferably used. By using dry etching, the sidewall of the opening becomes sharp and a fine pattern can be formed.

Next, a heat insulating layer 304 is selectively formed over the reflective layer 302. The heat insulating layer 304 is a layer for suppressing the first material layer 305 located in the region overlapping with the reflective layer 302 from being heated and sublimated. As the heat insulating layer 304, for example, titanium oxide, silicon oxide, silicon oxynitride, zirconium oxide, titanium carbide, or the like can be preferably used. Note that the heat insulating layer 304 is formed using a material having lower thermal conductivity than the material used for the reflective layer 302 and the absorbing layer 303. Note that in this specification, oxynitride is a substance having a higher oxygen content than nitrogen in its composition.

The heat insulating layer 304 can be formed using various methods. For example, it can be formed by sputtering, electron beam evaporation, vacuum evaporation, CVD, or the like. Moreover, although the film thickness of a heat insulation layer changes with materials, it is 10 nm or more and 2 micrometers or less, Preferably it can be 100 nm or more and 600 nm or less. By setting the thickness of the heat insulating layer 304 to 10 nm or more and 2 μm or less, even when the reflective layer 302 is heated, an effect of blocking heat conduction to the first material layer positioned on the reflective layer 302 is achieved. Have.

The heat insulating layer 304 has an opening formed in a region overlapping with the opening of the reflective layer 302. Various methods can be used for forming the pattern of the heat insulating layer 304, but dry etching is preferably used. By using dry etching, the patterned heat insulating layer 304 has a sharp side wall, and a fine pattern can be formed.

Note that when pattern formation of the heat insulating layer 304 and the reflective layer 302 is performed by a single etching process, the sidewalls of the openings provided in the heat insulating layer 304 and the reflective layer 302 can be aligned, and a finer pattern can be formed. This is preferable.

In this embodiment mode, the heat insulating layer 304 is formed only at a position overlapping the reflective layer 302, but the heat insulating layer 304 may be formed to cover the reflective layer 302 and the opening of the reflective layer 302. In this case, the heat insulating layer 304 needs to have a property of transmitting visible light.

Next, the absorption layer 303 is formed over the heat insulating layer 304. The absorption layer 303 can be formed using a material similar to that of the absorption layer 103 described in Embodiment 1. Note that the absorption layer 303 may be selectively formed. For example, after the absorption layer 303 is formed over the entire surface of the first substrate 301, the absorption layer 303 is patterned, and the pattern is formed in an island shape so as to cover the openings of the reflective layer 302 and the heat insulating layer 304. In this case, compared to the case where the absorption layer is formed on the entire surface, heat can be prevented from being conducted in the surface direction in the absorption layer, so that a finer EL layer pattern can be formed and a high-performance light emitting device can be realized. can do.

Next, the protective layer 306 is formed over the absorption layer 303. The protective layer 306 is formed in order to prevent a substance used for the absorption layer 303 from being sublimated and mixed as an impurity in an EL layer formed over the deposition target substrate. The protective layer 306 prevents the absorption layer 303 from being oxidized, altered, or deformed by heat. By forming the protective layer 306, deterioration of the absorption layer 303 can be prevented, so that the deposition substrate can be used more frequently. Therefore, the consumption and cost of the material can be suppressed. As the protective layer 306, for example, silicon nitride (SiNx), silicon nitride oxide, titanium oxide, silicon oxide, silicon oxynitride, zirconium oxide, titanium nitride, titanium carbide, or indium tin oxide (ITO: Indium Tin Oxide) Etc. The thickness of the protective layer 306 is preferably such that the absorbing layer 303 can be well protected, and can be, for example, about 100 nm. Note that the protective layer 306 is not necessarily provided. Further, the protective layer 306 may be selectively formed in a portion overlapping with the absorption layer 303.

Next, the first material layer 305 is formed over the protective layer 306. The first material layer 305 includes a first film formation material, a second film formation material, and a polymer compound. The structure described in Embodiment 1 can be applied to the first film formation material, the second film formation material, and the polymer compound included in the first material layer 305. Further, the first material layer 305 may be selectively formed. Here, the glass transition temperature of the polymer compound satisfies the following formula (1). More preferably, a polymer compound having a glass transition temperature satisfying the following mathematical formula (2) is used. Note that in the following formulas (1) and (2), the sublimation temperatures of the first film-forming material and the second film-forming material are measured at the same degree of vacuum (for example, a degree of vacuum of 10 ⁻³ Pa).

(In the formula (1) (2), S represents the glass transition temperature (℃) of the polymer compound, T _a, of the first film forming material or the second sublimation temperature of the film forming material (℃) High temperature (℃))

If the glass transition temperature of the polymer compound satisfies the above formula (1), preferably the above formula (2), the temperature reaches the lower one of the sublimation temperatures of the first film forming material or the second film forming material. However, the film-forming material that has reached the sublimation temperature is hardly transferred from the first material layer. This is because the polymer compound suppresses the movement of the first film formation material and the second film formation material in the first material layer. When the temperature of the first film formation material or the second film formation material exceeds a high temperature, the first film formation material and the second film formation material move in the first material layer. Is easily transferred onto the film formation substrate. Accordingly, there is little time difference between the transfer of the first film formation material and the transfer of the second film formation material, and an EL layer with a small concentration gradient can be formed over the deposition target substrate.

However, when the glass transition temperature of the polymer compound is lower than the range of the above mathematical formula (1), the first film-forming material and the second film-forming material are hardly suppressed from moving in the first material layer. When the temperature reaches the lower sublimation temperature of the first film forming material or the second film forming material, the film forming material having the lower sublimation temperature is transferred first, and then the film forming material having the higher sublimation temperature is transferred. The Further, if the glass transition temperature of the polymer compound is higher than the range of the mathematical formula (1), the first film-forming material and the second film-forming material after the first sublimation temperature exceeds a high temperature, The film-forming material and the second film-forming material are prevented from moving in the first material layer, and transfer is not easily performed.

Therefore, as the polymer compound 105c, a polymer compound having a glass transition temperature that satisfies the above formula (1), preferably the above formula (2) is used. Note that in this embodiment mode, transfer means that the first film formation material or the second film formation material included in the first material layer is transferred onto the deposition target substrate.

Next, a deposition method using the deposition substrate illustrated in FIG. 2A will be described with reference to FIGS. First, as illustrated in FIG. 2B, the second substrate 307 is disposed on the first substrate 301 at a position facing the surface on which the first material layer 305 and the like are formed. Note that here, in order to describe the case where the EL layer of the light-emitting element is formed using the deposition substrate of one embodiment of the present invention, the first substrate which is one electrode of the light-emitting element is formed over the second substrate 307. The electrode layer 308 is provided. An end portion of the first electrode layer 308 is preferably covered with an insulator 311. In this embodiment mode, the first electrode layer indicates an electrode which serves as an anode or a cathode of the light emitting element.

The surface of the first material layer 305 and the surface of the second substrate 307 are arranged with an interval of a distance d. Here, the distance d is 0 mm to 2 mm, preferably 0 mm to 0.05 mm, and more preferably 0 mm to 0.03 mm.

Note that the distance d is a distance between the surface of the first material layer containing the first film formation material, the second film formation material, and the polymer compound on the first substrate and the surface of the second substrate. It shall be defined in However, when a certain film (for example, a conductive film or a partition wall functioning as an electrode) is formed over the second substrate and the surface of the deposition target substrate has unevenness, the distance d is equal to the first distance on the first substrate. The surface of the first material layer containing the film forming material, the second film forming material and the polymer compound, and the outermost surface of the layer formed on the second substrate, that is, these films (conductive film or partition wall) Etc.) is defined by the distance from the surface.

Then, as shown in FIG. 2C, the first material layer 305 is subjected to heat treatment from the back surface of the first substrate 301, that is, the other surface side of the first substrate 301 on which the material layer is formed. The first film-forming material and the second film-forming material included in the film are formed on the second substrate 307. Thus, a second material layer 309 that is an EL layer of the light-emitting element is selectively formed over the second substrate 307.

In this embodiment, for example, when a lamp is used as a light source, the light 310 irradiated from the back surface of the first substrate 301 is reflected in the region where the reflective layer 302 is formed and is provided in the reflective layer 302. The light passes through the opening 312 and is absorbed by the absorption layer 303 in a region overlapping with the opening. The absorbed light is converted into thermal energy, whereby the first material layer 305 in contact with the absorption layer 303 in the region is heated, and the first film formation material and the second film formation material are converted into the second material. A film is formed on the substrate.

Note that when the first substrate 301 is irradiated with the light 310, the heat generated in the absorption layer 303 is conducted in the surface direction and the reflective layer 302 in contact with the absorption layer may be heated. Even if the reflective layer 302 is formed using a material having a reflectance of 85% or more, some heat is absorbed depending on the amount of heat of light to be irradiated. However, in the deposition substrate in this embodiment, the heat insulating layer 304 formed of a material having low thermal conductivity is provided between the reflective layer 302 and the first material layer 305. Even when 302 is heated, heat conduction to the first material layer 305 can be blocked in the heat insulating layer 304. Thus, the first film-forming material and the second film-forming material included in the first material layer 305 in the region overlapping with the opening 312 are selectively formed over the deposition target substrate, and the second As the material layer 309, an EL layer having a desired pattern can be formed.

In this embodiment mode, in order to selectively heat a region in contact with the absorption layer in the material layer formed over the first substrate, light is emitted as compared with the case where the entire surface of the first material layer is heated. The irradiation time may be relatively short. For example, in the case where a halogen lamp is used as a light source, by holding 500 ° C. to 800 ° C. for about 7 to 15 seconds, a region of the first material layer 305 that overlaps with the openings of the reflective layer 302 and the heat insulating layer 304 is formed. The first film-forming material and the second film-forming material can be formed on the deposition target substrate by heating.

Note that although the case where the second substrate which is a deposition target substrate is located below the first substrate which is a supporting substrate is illustrated in this embodiment mode, this embodiment mode is not limited thereto. The direction in which the substrate is installed can be set as appropriate.

As described above, the reflective layer and the heat insulating layer are selectively formed on the first substrate, and the absorption layer, the protective layer, and the first film forming material are formed on the first substrate and the heat insulating layer. When the second deposition material and the material layer including the polymer compound are formed, the first deposition material, the second deposition material, and the material layer including the polymer compound are selectively heated to form a layer. Pattern formation of the second material layer formed on the film substrate can be performed.

Furthermore, since the film formation method described in this embodiment includes a polymer compound that satisfies the above formula (1), preferably the above formula (2), in the first material layer, Even if the sublimation temperature of the film-forming material 2 reaches a lower temperature, the film-forming material that has reached the sublimation temperature is not easily transferred from the first material layer. This is because the high molecular compound suppresses the movement of the first film-forming material and the second film-forming material in the first material layer. When the temperature of the first film formation material or the second film formation material exceeds a high temperature, the first film formation material and the second film formation material move in the first material layer. Is easily transferred onto the film formation substrate. Accordingly, there is little time difference between the transfer of the first film formation material and the transfer of the second film formation material, and an EL layer with a small concentration gradient can be formed over the deposition target substrate.

Note that this embodiment can be freely combined with any of the other embodiments.

(Embodiment 3)
In this embodiment, a light-emitting device capable of full-color display by forming an EL layer of a light-emitting element using a plurality of deposition substrates in the film formation method of one embodiment of the present invention described in Embodiment 2 A manufacturing method of will be described.

In Embodiments 1 and 2, an EL layer made of the same material is formed over a plurality of electrodes formed over a second substrate, which is a deposition substrate, in one film formation step. In this embodiment, the case where any one of three types of EL layers having different light emission is formed over a plurality of electrodes formed over the second substrate will be described.

First, three deposition substrates shown in FIG. 2A in Embodiment Mode 2 are prepared. However, a material layer including a first film formation material, a second film formation material, and a polymer compound for forming EL layers having different light emission is formed on each supporting substrate. Specifically, the composition layer includes a material layer (R) including a first film-forming material, a second film-forming material, and a polymer compound for forming an EL layer (EL layer (R)) that emits red light. A film layer (R) and a material layer (G) including a first film forming material, a second film forming material, and a polymer compound for forming an EL layer (EL layer (G)) that emits green light. And a material layer containing a first film-forming material, a second film-forming material, and a polymer compound for forming an EL layer (EL layer (B)) that emits blue light. A film-forming substrate (B) having (B) is prepared.

In addition, one deposition target substrate having a plurality of first electrodes illustrated in FIG. 2B in Embodiment Mode 2 is prepared. Note that as illustrated in FIG. 3B, the end portions of the plurality of first electrodes over the deposition target substrate are covered with the insulator 414, and thus the light-emitting region is formed using the first electrode. It corresponds to a part of the region that is exposed without overlapping with the insulator.

First, as a first film formation step, the film formation substrate and the film formation substrate (R) are overlapped and aligned as in FIG. Note that an alignment marker is preferably provided on the deposition target substrate. In addition, it is preferable to provide an alignment marker on the deposition substrate (R). Note that since the absorption substrate, the material layer, and the like are provided on the deposition substrate (R), the absorption layer, the material layer, and the like around the alignment marker are preferably removed in advance.

Then, light is irradiated from the back surface side (the surface on which the reflective layer 302, the heat insulating layer 304, the absorption layer 303, the protective layer 306, and the first material layer 305 shown in FIG. 2 are not formed) of the deposition substrate (R). To do. The absorption layer absorbs the irradiated light and applies heat to the material layer (R), whereby the first film formation material and the second film formation material included in the material layer (R) are heated, An EL layer (R) is formed over part of the first electrode over the deposition substrate. After the first film formation, the film formation substrate (R) is moved to a place away from the film formation substrate.

Next, as a second film formation step, the film formation substrate and the film formation substrate (G) are overlapped and aligned. In the film formation substrate (G), an opening portion of the reflective layer is formed so as to be shifted by one pixel from the film formation substrate (R) used in the first film formation.

Then, light is irradiated from the back surface side (the surface on which the reflective layer 302, the heat insulating layer 304, the absorption layer 303, the protective layer 306, and the first material layer 305 shown in FIG. 2 are not formed) of the deposition substrate (G). To do. The absorption layer absorbs the irradiated light and applies heat to the material layer (G), whereby the first film formation material and the second film formation material included in the material layer (G) are heated, The EL layer (G) is formed on a part of the deposition substrate and on the first electrode next to the first electrode on which the EL layer (R) is formed in the first deposition. After the second deposition, the deposition substrate (G) is moved to a location away from the deposition target substrate.

Next, as a third film formation step, the film formation substrate and the film formation substrate (B) are overlapped and aligned. In the film formation substrate (B), an opening portion of the reflective layer is formed by being shifted by two pixels from the film formation substrate (B) used in the first film formation.

Then, light is irradiated from the back surface side (the surface on which the reflective layer 302, the heat insulating layer 304, the absorption layer 303, the protective layer 306, and the first material layer 305 shown in FIG. 2 are not formed) of the film formation substrate (B). To do. The state immediately before the third film formation corresponds to the top view of FIG. In FIG. 3A, the reflective layer 401 has an opening 402. Therefore, the light transmitted through the opening 402 of the reflective layer 401 of the deposition substrate (B) is transmitted through the heat insulating layer and absorbed by the absorption layer. In addition, a first electrode is formed in a region overlapping with the opening 402 of the deposition substrate (B) of the deposition substrate. Note that the EL layer (R) 411 already formed by the first film formation and the second film formation are formed over the deposition target substrate below the region indicated by the dotted line in FIG. The EL layer (G) 412 is located.

Then, the EL layer (B) 413 is formed by the third deposition. The absorption layer absorbs the irradiated light and applies heat to the material layer (B), whereby the first film formation material and the second film formation material included in the material layer (B) are heated, An EL layer (B) 413 is formed on a part of the deposition substrate and on the first electrode next to the first electrode on which the EL layer (G) 412 is formed in the second deposition. . After the third deposition, the deposition substrate (B) is moved to a location away from the deposition target substrate.

In this manner, the EL layer (R) 411, the EL layer (G) 412, and the EL layer (B) 413 can be formed over the same deposition substrate at regular intervals (see FIG. 3B). A light emitting element can be formed by forming a second electrode over these films.

Through the above process, a light-emitting element capable of full color display can be formed by forming light-emitting elements that emit different light on the same substrate.

Although FIG. 3 shows an example in which the shape of the opening 402 of the reflective layer formed on the deposition substrate is rectangular, the shape is not particularly limited, and may be a stripe-shaped opening. In the case of a stripe-shaped opening, a film is also formed between light emitting regions having the same light emission color. However, since the film is formed on the insulator 414, a portion overlapping with the insulator 414 is not a light emitting region. .

Further, the pixel arrangement is not particularly limited, and one pixel shape may be a polygon, for example, a hexagon. Note that in order to form a polygonal pixel, a film formation substrate having a reflective layer having a polygonal opening may be used.

Note that in this embodiment mode, three film formation substrates are used to form three types of EL layers having different light emission. However, a material layer (R) and a material layer ( G) and the material layer (B) may be selectively formed. In this case, the deposition substrate and the deposition substrate need only be aligned once, which is preferable because the utilization efficiency and productivity of the material are increased.

In manufacturing a light-emitting device capable of full-color display described in this embodiment, a film is formed over the deposition target substrate by controlling the thickness of the material layer formed over the deposition substrate of one embodiment of the present invention. The thickness of the film to be formed can be controlled. That is, the film formed on the deposition target substrate by heating all of the first deposition material and the second deposition material included in the material layer formed on the deposition substrate has a desired thickness. Therefore, since the film thickness of the material layer is controlled in advance, it is not necessary to monitor the film thickness when the film is formed on the deposition target substrate. Therefore, it is not necessary for the user to adjust the deposition rate using the film thickness monitor, and the film forming process can be fully automated. Therefore, productivity can be improved.

In addition, in the manufacturing of the light-emitting device capable of full-color display described in this embodiment, the light-emitting device is included in the material layer formed over the deposition substrate by being manufactured using the deposition method of one embodiment of the present invention. The first deposition material and the second deposition material can be deposited on the deposition target substrate without causing a concentration gradient. Therefore, in the film formation method of one embodiment of the present invention, a layer including the first film formation material and the second film formation material having different sublimation temperatures is formed without performing complicated control of an evaporation rate or the like. A film can be easily and accurately formed on a substrate.

Further, in the manufacture of the light-emitting device capable of full color display described in this embodiment, a flat and uniform film can be formed by using the film formation method of one embodiment of the present invention. In addition, since a fine pattern can be formed, a highly accurate light-emitting device can be obtained.

Further, in manufacturing a light-emitting device capable of full-color display described in this embodiment, a desired first film formation material and second film formation are performed by using the film formation method of one embodiment of the present invention. It is possible to form a film on a deposition target substrate without wasting materials. Accordingly, the utilization efficiency of the first film-forming material and the second film-forming material can be improved, and the manufacturing cost can be reduced. In addition, it is possible to prevent the first film formation material and the second film formation material from adhering to the film formation chamber wall, and the maintenance of the film formation apparatus can be simplified.

Note that the structure described in this embodiment can be combined with any of the structures described in Embodiments 1 and 2 as appropriate.

(Embodiment 4)
In this embodiment, a method for manufacturing a light-emitting element and a light-emitting device by applying the film formation method of one embodiment of the present invention will be described.

For example, the light-emitting element illustrated in FIGS. 4A and 4B can be manufactured. In the light-emitting element illustrated in FIG. 4A, a first electrode 902, an EL layer 903 formed using only the light-emitting layer 913, and a second electrode 904 are sequentially stacked over a substrate 901. One of the first electrode 902 and the second electrode 904 functions as an anode, and the other functions as a cathode. The holes injected from the anode and the electrons injected from the cathode are recombined in the EL layer 903, so that light emission can be obtained. In this embodiment mode, the first electrode 902 is an electrode that functions as an anode, and the second electrode 904 is an electrode that functions as a cathode.

4B illustrates the case where the EL layer 903 in FIG. 4A has a structure in which a plurality of layers are stacked. Specifically, the light-emitting element illustrated in FIG. The hole injection layer 911, the hole transport layer 912, the light emitting layer 913, the electron transport layer 914, and the electron injection layer 915 are sequentially provided. Note that the EL layer 903 functions as long as it has at least the light-emitting layer 913 as illustrated in FIG. 4A. Therefore, it is not necessary to provide all of these layers, and the EL layer 903 is appropriately selected as necessary. It ’s fine.

As the substrate 901 illustrated in FIG. 4, a substrate having an insulating surface or an insulating substrate is used. Specifically, various glass substrates, quartz substrates, ceramic substrates, sapphire substrates and the like used for the electronic industry such as aluminosilicate glass, aluminoborosilicate glass, and barium borosilicate glass can be used.

The first electrode 902 and the second electrode 904 can be formed using various metals, alloys, electrically conductive compounds, mixtures thereof, and the like. Specifically, for example, indium tin oxide (ITO), indium oxide-tin oxide containing silicon or silicon oxide, indium zinc oxide (IZO), tungsten oxide, and oxide. Examples thereof include indium oxide containing zinc. In addition, gold (Au), platinum (Pt), nickel (Ni), tungsten (W), chromium (Cr), molybdenum (Mo), iron (Fe), cobalt (Co), copper (Cu), palladium ( Pd), or a nitride of a metal material (for example, titanium nitride).

These materials are usually formed by sputtering. For example, indium oxide-zinc oxide can be formed by a sputtering method using a target in which 1 to 20 wt% of zinc oxide is added to indium oxide. Further, indium oxide containing tungsten oxide and zinc oxide can be formed by a sputtering method using a target containing 0.5 to 5 wt% tungsten oxide and 0.1 to 1 wt% zinc oxide with respect to indium oxide. it can. In addition, a sol-gel method or the like may be applied to produce the ink-jet method or the spin coat method.

Alternatively, aluminum (Al), silver (Ag), an alloy containing aluminum, or the like can be used. In addition, materials having a small work function, elements belonging to Group 1 or Group 2 of the periodic table of elements, that is, alkali metals such as lithium (Li) and cesium (Cs), and magnesium (Mg) and calcium (Ca) , Alkaline earth metals such as strontium (Sr), and alloys containing them (aluminum, alloys of magnesium and silver, alloys of aluminum and lithium), rare earth metals such as europium (Eu), ytterbium (Yb), and the like An alloy containing the same can also be used.

A film of an alkali metal, an alkaline earth metal, or an alloy containing these can be formed using a vacuum evaporation method. An alloy containing an alkali metal or an alkaline earth metal can also be formed by a sputtering method. Further, a silver paste or the like can be formed by an inkjet method or the like. Further, the first electrode 902 and the second electrode 904 are not limited to a single layer film and can be formed using a stacked film.

Note that in order to extract light emitted from the EL layer 903 to the outside, one or both of the first electrode 902 and the second electrode 904 are formed so as to pass light. For example, a conductive material that transmits visible light such as indium tin oxide is used, or silver, aluminum, or the like is formed to have a thickness of several nanometers to several tens of nanometers. Alternatively, a stacked structure of a thin metal film such as silver or aluminum and a thin film using a conductive material having a light-transmitting property with respect to visible light such as an ITO film can be used.

Note that the EL layer 903 (the hole-injection layer 911, the hole-transport layer 912, the light-emitting layer 913, the electron-transport layer 914, or the electron-injection layer 915) of the light-emitting element described in this embodiment is described in Embodiment Modes 1 to You may form by applying the film-forming method shown in the form 3.

For example, in the case of forming the light-emitting element illustrated in FIG. 4A, the material layer of the deposition substrate described in Embodiment 3 is formed using a plurality of materials for forming the EL layer 903, and the deposition substrate is formed. Is used to form an EL layer 903 over the first electrode 902 over the substrate 901. Then, by forming the second electrode 904 over the EL layer 903, the light-emitting element illustrated in FIG. 4A can be obtained.

In the case of forming the light-emitting element illustrated in FIG. 4B, each layer of the EL layer 903 (a hole injection layer 911, a hole transport layer 912, an electron transport layer 914, and an electron injection layer 915) is formed. The deposition substrate described in any of Embodiments 1 to 3 having a material layer formed using a plurality of materials is prepared for each layer, and a different deposition substrate is used for each layer deposition. The EL layer 903 is formed over the first electrode 902 over the substrate 901 by the method described in the above embodiment mode. Then, by forming the second electrode 904 over the EL layer 903, the light-emitting element illustrated in FIG. 4B can be obtained. In this case, the method described in any of Embodiments 1 to 3 may be used for all layers of the EL layer 903, or Embodiments 1 to 3 may be used for only some layers. You may use the method shown by.

For example, as the hole injection layer 911, molybdenum oxide, vanadium oxide, ruthenium oxide, tungsten oxide, manganese oxide, or the like can be used. In addition, phthalocyanine compounds such as phthalocyanine (abbreviation: H ₂ Pc) and copper phthalocyanine (abbreviation: CuPc), or poly (3,4-ethylenedioxythiophene) / poly (styrenesulfonic acid) (PEDOT / PSS) The hole injection layer can also be formed by a polymer such as the above.

As the hole-injecting layer 911, a layer containing a substance having a high hole-transport property and a substance showing an electron-accepting property can be used. A layer including a substance having a high hole-transport property and a substance having an electron-accepting property has a high carrier density and an excellent hole-injection property. In addition, by using a layer containing a substance having a high hole transporting property and a substance showing an electron accepting property as a hole injection layer in contact with the electrode functioning as the anode, the work function of the electrode material functioning as the anode can be reduced. Regardless, various metals, alloys, electrically conductive compounds, mixtures thereof, and the like can be used.

The layer containing a substance having a high hole-transport property and a substance having an electron-accepting property is formed, for example, by stacking a layer containing a substance having a high hole-transport property and a layer containing a substance having an electron-accepting property. Can do.

As a substance having an electron accepting property used for the hole injection layer 911, 7,7,8,8-tetracyano-2,3,5,6-tetrafluoroquinodimethane (abbreviation: F4-TCNQ), chloranil, and the like can be used. Can be mentioned. Moreover, a transition metal oxide can be mentioned. In addition, oxides of metals belonging to Groups 4 to 8 in the periodic table can be given. Specifically, vanadium oxide, niobium oxide, tantalum oxide, chromium oxide, molybdenum oxide, tungsten oxide, manganese oxide, and rhenium oxide are preferable because of their high electron accepting properties. Among these, molybdenum oxide is especially preferable because it is stable in the air, has a low hygroscopic property, and is easy to handle.

As the substance having a high hole-transport property used for the hole-injection layer 911, various compounds such as an aromatic amine compound, a carbazole derivative, an aromatic hydrocarbon, an oligomer, a dendrimer, and a polymer can be used. Note that the substance having a high hole-transport property used for the hole-injection layer is preferably a substance having a hole mobility of 10 ⁻⁶ cm ² / Vs or higher. Note that other than these substances, any substance that has a property of transporting more holes than electrons may be used. Hereinafter, substances having a high hole-transport property that can be used for the hole-injection layer 911 are specifically listed.

As an aromatic amine compound that can be used for the hole-injection layer 911, for example, 4,4′-bis [N- (1-naphthyl) -N-phenylamino] biphenyl (abbreviation: NPB), N, N ′ -Bis (3-methylphenyl) -N, N′-diphenyl- [1,1′-biphenyl] -4,4′-diamine (abbreviation: TPD), 4,4 ′, 4 ″ -tris (N, N-diphenylamino) triphenylamine (abbreviation: TDATA), 4,4 ′, 4 ″ -tris [N- (3-methylphenyl) -N-phenylamino] triphenylamine (abbreviation: MTDATA), 4, 4′-bis [N- (spiro-9,9′-bifluoren-2-yl) -N-phenylamino] biphenyl (abbreviation: BSPB) or the like can be used. N, N′-bis (4-methylphenyl) (p-tolyl) -N, N′-diphenyl-p-phenylenediamine (abbreviation: DTDPPA), 4,4′-bis [N- (4-diphenyl) Aminophenyl) -N-phenylamino] biphenyl (abbreviation: DPAB), 4,4′-bis (N- {4- [N ′-(3-methylphenyl) -N′-phenylamino] phenyl} -N— Phenylamino) biphenyl (abbreviation: DNTPD), 1,3,5-tris [N- (4-diphenylaminophenyl) -N-phenylamino] benzene (abbreviation: DPA3B), and the like.

As a carbazole derivative that can be used for the hole-injection layer 911, specifically, 3- [N- (9-phenylcarbazol-3-yl) -N-phenylamino] -9-phenylcarbazole (abbreviation: PCzPCA1) ), 3,6-bis [N- (9-phenylcarbazol-3-yl) -N-phenylamino] -9-phenylcarbazole (abbreviation: PCzPCA2), 3- [N- (1-naphthyl) -N- (9-phenylcarbazol-3-yl) amino] -9-phenylcarbazole (abbreviation: PCzPCN1), 4,4′-di (N-carbazolyl) biphenyl (abbreviation: CBP), 1,3,5-tris [4 -(N-carbazolyl) phenyl] benzene (abbreviation: TCPB), 9- [4- (N-carbazolyl) phenyl] -10-phenylanthrace (Abbreviation: CzPA), and 1,4-bis [4-(N-carbazolyl) phenyl] -2,3,5,6-tetraphenylbenzene.

Examples of aromatic hydrocarbons that can be used for the hole injection layer 911 include 2-tert-butyl-9,10-di (2-naphthyl) anthracene (abbreviation: t-BuDNA), 2-tert- Butyl-9,10-di (1-naphthyl) anthracene, 9,10-bis (3,5-diphenylphenyl) anthracene (abbreviation: DPPA), 2-tert-butyl-9,10-bis (4-phenylphenyl) ) Anthracene (abbreviation: t-BuDBA), 9,10-di (2-naphthyl) anthracene (abbreviation: DNA), 9,10-diphenylanthracene (abbreviation: DPAnth), 2-tert-butylanthracene (abbreviation: t-) BuAnth), 9,10-bis (4-methyl-1-naphthyl) anthracene (abbreviation: DMNA), 9,10-bis [2 (1-naphthyl) phenyl] -2-tert-butyl-anthracene, 9,10-bis [2- (1-naphthyl) phenyl] anthracene, 2,3,6,7-tetramethyl-9,10-di ( 1-naphthyl) anthracene, 2,3,6,7-tetramethyl-9,10-di (2-naphthyl) anthracene, 9,9′-bianthryl, 10,10′-diphenyl-9,9′-bianthryl, 10,10′-bis (2-phenylphenyl) -9,9′-bianthryl, 10,10′-bis [(2,3,4,5,6-pentaphenyl) phenyl] -9,9′-bianthryl , Anthracene, tetracene, rubrene, perylene, 2,5,8,11-tetra (tert-butyl) perylene, and the like. In addition, pentacene, coronene, and the like can also be used. Thus, it is more preferable to use an aromatic hydrocarbon having a hole mobility of 1 × 10 ⁻⁶ cm ² / Vs or more and having 14 to 42 carbon atoms.

Note that the aromatic hydrocarbon that can be used for the hole-injection layer 911 may have a vinyl skeleton. As the aromatic hydrocarbon having a vinyl group, for example, 4,4′-bis (2,2-diphenylvinyl) biphenyl (abbreviation: DPVBi), 9,10-bis [4- (2,2- Diphenylvinyl) phenyl] anthracene (abbreviation: DPVPA) and the like.

In addition, a layer including a substance having a high hole-transport property and a substance having an electron-accepting property has not only a hole-injection property but also a good hole-transport property. It may be used as a transport layer.

The hole transport layer 912 is a layer containing a substance having a high hole transport property, and examples of the substance having a high hole transport property include 4,4′-bis [N- (1-naphthyl) -N -Phenylamino] biphenyl (abbreviation: NPB or α-NPD) and N, N′-bis (3-methylphenyl) -N, N′-diphenyl- [1,1′-biphenyl] -4,4′-diamine (Abbreviation: TPD), 4,4 ′, 4 ″ -tris (N, N-diphenylamino) triphenylamine (abbreviation: TDATA), 4,4 ′, 4 ″ -tris [N- (3-methyl Phenyl) -N-phenylamino] triphenylamine (abbreviation: MTDATA), 4,4′-bis [N- (spiro-9,9′-bifluoren-2-yl) -N-phenylamino] biphenyl (abbreviation: Use aromatic amine compounds such as BSPB) It can be. The substances described here are mainly substances having a hole mobility of 10 ⁻⁶ cm ² / Vs or higher. Note that other than these substances, any substance that has a property of transporting more holes than electrons may be used. Note that the layer containing a substance having a high hole-transport property is not limited to a single layer, and two or more layers containing the above substances may be stacked.

The electron-transport layer 914 is a layer containing a substance having a high electron-transport property. For example, tris (8-quinolinolato) aluminum (abbreviation: Alq), tris (4-methyl-8-quinolinolato) aluminum (abbreviation: Almq ₃ ). Bis (10-hydroxybenzo [h] quinolinato) beryllium (abbreviation: BeBq ₂ ), bis (2-methyl-8-quinolinolato) (4-phenylphenolato) aluminum (abbreviation: BAlq), quinoline skeleton or benzoquinoline A metal complex having a skeleton can be used. In addition, bis [2- (2-hydroxyphenyl) benzoxazolate] zinc (abbreviation: Zn (BOX) ₂ ), bis [2- (2-hydroxyphenyl) benzothiazolate] zinc (abbreviation: Zn (BTZ)) A metal complex having an oxazole-based or thiazole-based ligand such as ₂ ) can also be used. In addition to metal complexes, 2- (4-biphenylyl) -5- (4-tert-butylphenyl) -1,3,4-oxadiazole (abbreviation: PBD), 1,3-bis [5 -(P-tert-butylphenyl) -1,3,4-oxadiazol-2-yl] benzene (abbreviation: OXD-7), 3- (4-biphenylyl) -4-phenyl-5- (4- tert-Butylphenyl) -1,2,4-triazole (abbreviation: TAZ01) bathophenanthroline (abbreviation: BPhen), bathocuproin (abbreviation: BCP), and the like can also be used. The substances mentioned here are mainly substances having an electron mobility of 10 ⁻⁶ cm ² / Vs or higher. Note that other than the above substances, any substance that has a property of transporting more electrons than holes may be used for the electron-transport layer. Further, the electron-transport layer is not limited to a single layer, and two or more layers including the above substances may be stacked.

As the electron injection layer 915, an alkali metal compound such as lithium fluoride (LiF), cesium fluoride (CsF), calcium fluoride (CaF ₂ ), or the like, or an alkaline earth metal compound can be used. Further, a layer in which a substance having an electron transporting property and an alkali metal or an alkaline earth metal are combined can also be used. For example, Alq containing magnesium (Mg) can be used. Note that it is more preferable to use a layer in which an electron-transporting substance and an alkali metal or an alkaline earth metal are combined as the electron-injecting layer because electron injection from the second electrode 904 occurs efficiently.

Note that there is no particular limitation on the layered structure of the EL layer 903, and a substance having a high electron-transport property, a substance having a high hole-transport property, a substance having a high electron-injection property, a substance having a high hole-injection property, or a bipolar property A layer including a substance (a substance having a high electron and hole transport property) and the light-emitting layer may be combined as appropriate.

Light emission obtained in the EL layer 903 is extracted outside through one or both of the first electrode 902 and the second electrode 904. Therefore, one or both of the first electrode 902 and the second electrode 904 are electrodes having a property of transmitting visible light. In the case where only the first electrode 902 is an electrode having a property of transmitting visible light, light is extracted from the substrate 901 side through the first electrode 902. In the case where only the second electrode 904 is an electrode having a property of transmitting visible light, light is extracted from the side opposite to the substrate 901 through the second electrode 904. In the case where each of the first electrode 902 and the second electrode 904 is an electrode having a property of transmitting visible light, light passes through the first electrode 902 and the second electrode 904 and passes through the substrate 901 side and the substrate 901. And taken out from both sides.

Note that FIG. 4 illustrates the structure in which the first electrode 902 functioning as an anode is provided on the substrate 901 side; however, the second electrode 904 functioning as a cathode may be provided on the substrate 901 side.

Further, as a formation method of the EL layer 903, the film formation method described in Embodiment Mode 1 may be used, or another film formation method may be combined. Moreover, you may form using the different film-forming method for each electrode or each layer. Examples of the dry method include vacuum vapor deposition, electron beam vapor deposition, and sputtering. Examples of the wet method include an inkjet method and a spin coat method.

In the light-emitting element of this embodiment, an EL layer to which one embodiment of the present invention is applied can be formed, and thus a film with a small concentration gradient can be formed efficiently. Therefore, the yield can be improved and the cost can be reduced.

(Embodiment 5)
In this embodiment, a light-emitting device formed using the light-emitting element described in Embodiment 4 will be described.

First, a passive matrix light-emitting device is described with reference to FIGS.

A light emitting device of a passive matrix type (also referred to as a simple matrix type) is provided so that a plurality of anodes arranged in stripes (bands) and a plurality of cathodes arranged in stripes are orthogonal to each other. The light emitting layer is sandwiched between the intersections. Therefore, the pixel corresponding to the intersection between the selected anode (to which voltage is applied) and the selected cathode is turned on.

5A is a diagram illustrating a top view of the pixel portion before sealing, and a cross-sectional view taken along the chain line AA ′ in FIG. 5A is FIG. FIG. 5C is a cross-sectional view taken along −B ′.

An insulating layer 1004 is formed over the substrate 1001 as a base insulating layer. Note that the base insulating layer is not particularly required if it is not necessary. On the insulating layer 1004, a plurality of first electrodes 1013 are arranged in stripes at regular intervals. Further, a partition wall 1014 having an opening corresponding to each pixel is provided over the first electrode 1013, and the partition wall 1014 having an opening is formed using an insulating material (photosensitive or non-photosensitive organic material (polyimide, acrylic, Polyamide, polyimide amide, resist or benzocyclobutene), or SOG film (for example, an SiOx film containing an alkyl group)). Note that an opening corresponding to each pixel is a light emitting region 1021.

A plurality of reverse-tapered partition walls 1022 that are parallel to each other and intersect with the first electrode 1013 are provided over the partition wall 1014 having an opening. The reverse-tapered partition wall 1022 is formed by using a positive photosensitive resin as a pattern in the unexposed portion and adjusting the exposure amount or development time so that the lower portion of the pattern is etched more in accordance with the photolithography method.

The total height of the partition wall 1014 having an opening and the reverse-tapered partition wall 1022 is set to be larger than the film thickness of the EL layer and the second electrode 1016. Thereby, the EL layer separated into a plurality of regions, specifically, an EL layer (R) (1015R) formed of a material that emits red light, and an EL layer (G) (G) (formed of a material that emits green light) ( 1015G), an EL layer (B) (1015B) formed of a material that emits blue light, and a second electrode 1016 are formed. Note that the plurality of regions separated from each other are electrically independent.

The second electrode 1016 is a stripe-shaped electrode extending in a direction intersecting with the first electrode 1013 and parallel to each other. Note that a part of the conductive layer that forms the EL layer and the second electrode 1016 is also formed over the reverse-tapered partition wall 1022; however, the EL layer (R) (1015R) and the EL layer (G) (1015G) The EL layer (B) (1015B) and the second electrode 1016 are separated from each other. Note that the EL layer in this embodiment includes at least a light-emitting layer, and may include a hole injection layer, a hole transport layer, an electron transport layer, an electron injection layer, or the like in addition to the light-emitting layer. good.

Here, an EL layer (R) (1015R), an EL layer (G) (1015G), and an EL layer (B) (1015B) are selectively formed, and three types (red (R), blue (G), green An example of forming a light emitting device capable of full color display capable of obtaining the light emission of (B)) is shown. Note that the EL layers (R) (1015R), the EL layers (G) (1015G), and the EL layers (B) (1015B) are formed in stripe patterns parallel to each other. In order to form these EL layers, the film formation method described in any of Embodiments 1 to 3 may be applied.

If necessary, sealing is performed using a sealing material such as a sealing can or a glass substrate for sealing. Here, a glass substrate is used as the sealing substrate, and the substrate and the sealing substrate are bonded together using an adhesive such as a sealing material, and the space surrounded by the adhesive such as the sealing material is hermetically sealed. The sealed space is filled with a filler or a dry inert gas. In order to improve the reliability of the light emitting device, a desiccant or the like may be sealed between the substrate and the sealing material. A trace amount of water is removed by the desiccant, and it is sufficiently dried. As the desiccant, it is possible to use a substance that absorbs moisture by chemical adsorption, such as an oxide of an alkaline earth metal such as calcium oxide or barium oxide. As another desiccant, a substance that adsorbs moisture by physical adsorption, such as zeolite or silica gel, may be used.

However, in the case where a sealing material that covers and contacts the light emitting element is provided and is sufficiently shielded from the outside air, the desiccant is not necessarily provided.

Next, FIG. 6 shows a top view in the case where an FPC or the like is mounted on the passive matrix light-emitting device shown in FIG.

In FIG. 6, the pixel portions constituting the image display intersect so that the scanning line group and the data line group are orthogonal to each other.

Here, the first electrode 1013 in FIG. 5 corresponds to the scanning line 1103 in FIG. 6, the second electrode 1016 in FIG. 5 corresponds to the data line 1102 in FIG. 6, and the inversely tapered partition wall 1022 is formed. This corresponds to the partition wall 1104. An EL layer is sandwiched between the data line 1102 and the scanning line 1103, and an intersection indicated by a region 1105 corresponds to one pixel.

Note that the scanning line 1103 is electrically connected to the connection wiring 1108 at a wiring end, and the connection wiring 1108 is connected to the FPC 1109 b through the input terminal 1107. The data line is connected to the FPC 1109a via the input terminal 1106.

Further, if necessary, an optical film such as a polarizing plate or a circular polarizing plate (including an elliptical polarizing plate), a retardation plate (λ / 4 plate, λ / 2 plate), a color filter, etc. is appropriately provided on the exit surface. Also good. Further, an antireflection film may be provided on the polarizing plate or the circularly polarizing plate. For example, anti-glare treatment can be performed that diffuses reflected light due to surface irregularities and reduces reflection.

6 illustrates an example in which the driver circuit is not provided over the substrate, the present invention is not particularly limited, and an IC chip having the driver circuit may be mounted over the substrate.

When an IC chip is mounted, a data line side IC and a scanning line side IC in which a driving circuit for transmitting each signal to the pixel portion is formed in a peripheral (outside) region of the pixel portion by a COG method. . You may mount using TCP or a wire bonding system as mounting techniques other than a COG system. TCP is an IC mounted on a TAB tape, and the IC is mounted by connecting the TAB tape to a wiring on an element formation substrate. The data line side IC and the scanning line side IC may be one using a silicon substrate, or one in which a drive circuit is formed by a TFT on a glass substrate, a quartz substrate, or a plastic substrate. Further, although an example in which one IC is provided on one side has been described, it may be divided into a plurality of parts on one side.

Next, an example of an active matrix light-emitting device is described with reference to FIGS. 7A is a top view of the light-emitting device, and FIG. 7B is a cross-sectional view taken along the chain line A-A ′ in FIG. 7A. An active matrix light-emitting device according to this embodiment includes a pixel portion 1202 provided over an element substrate 1210, a driver circuit portion (source side driver circuit) 1201, a driver circuit portion (gate side driver circuit) 1203, and the like. Have. The pixel portion 1202, the driver circuit portion 1201, and the driver circuit portion 1203 are sealed between the element substrate 1210 and the sealing substrate 1204 with a sealant 1205.

Over the element substrate 1210, an external input terminal that transmits a signal (eg, a video signal, a clock signal, a start signal, or a reset signal) and a potential from the outside to the driver circuit portion 1201 and the driver circuit portion 1203 is provided. A lead wiring 1208 for connection is provided. In this example, an FPC (flexible printed circuit) 1209 is provided as an external input terminal. Although only the FPC is shown here, a printed wiring board (PWB) may be attached to the FPC. The light-emitting device in this specification includes not only a light-emitting device body but also a state in which an FPC or a PWB is attached thereto.

Next, a cross-sectional structure will be described with reference to FIG. A driver circuit portion and a pixel portion are formed over the element substrate 1210. Here, a driver circuit portion 1201 which is a source side driver circuit and a pixel portion 1202 are shown.

The driver circuit portion 1201 shows an example in which a CMOS circuit in which an n-channel TFT 1223 and a p-channel TFT 1224 are combined is formed. Note that the circuit forming the driver circuit portion may be formed of various CMOS circuits, PMOS circuits, or NMOS circuits. In this embodiment mode, a driver integrated type in which a driver circuit is formed over a substrate is shown; however, this is not necessarily required, and the driver circuit can be formed outside the substrate.

The pixel portion 1202 is formed by a plurality of pixels including a switching TFT 1211 and a first electrode 1213 electrically connected to a wiring (source electrode or drain electrode) of the current control TFT 1212 and the current control TFT 1212. The Note that an insulator 1214 is formed so as to cover an end portion of the first electrode 1213. Here, it is formed by using a positive photosensitive acrylic resin.

In addition, in order to improve the coverage of the film formed to be stacked on the upper layer, it is preferable that a curved surface having a curvature be formed at the upper end portion or the lower end portion of the insulator 1214. For example, in the case where a positive photosensitive acrylic resin is used as the material of the insulator 1214, it is preferable that the upper end portion of the insulator 1214 has a curved surface having a curvature radius (0.2 μm to 3 μm). As the insulator 1214, either a negative type that becomes insoluble in an etchant by photosensitive light or a positive type that becomes soluble in an etchant by light can be used. For example, both silicon oxide and silicon oxynitride can be used.

An EL layer 1200 and a second electrode 1216 are stacked over the first electrode 1213. Note that the first electrode 1213 is an ITO film, and a wiring film of a current control TFT 1212 connected to the first electrode 1213 is a laminated film of a titanium nitride film and a film containing aluminum as a main component, or a titanium nitride film and aluminum. When a laminated film including a main component film and a titanium nitride film is applied, the resistance as a wiring is low and good ohmic contact with the ITO film can be obtained. Although not shown here, the second electrode 1216 is electrically connected to an FPC 1209 which is an external input terminal.

The EL layer 1200 includes at least a light-emitting layer, and includes a hole injection layer, a hole transport layer, an electron transport layer, or an electron injection layer as appropriate in addition to the light-emitting layer. A light-emitting element 1215 is formed with a stacked structure of the first electrode 1213, the EL layer 1200, and the second electrode 1216.

In the cross-sectional view shown in FIG. 7B, only one light-emitting element 1215 is illustrated; however, in the pixel portion 1202, a plurality of light-emitting elements are arranged in a matrix. In the pixel portion 1202, light emitting elements capable of emitting three types (R, G, and B) of light emission can be selectively formed, so that a light emitting device capable of full color display can be formed. Alternatively, a light emitting device capable of full color display may be obtained by combining with a color filter.

Further, the sealing substrate 1204 is bonded to the element substrate 1210 with the sealant 1205, whereby the light-emitting element 1215 is provided in the space 1207 surrounded by the element substrate 1210, the sealing substrate 1204, and the sealant 1205. Yes. Note that the space 1207 includes a structure filled with a sealant 1205 in addition to a case where the space is filled with an inert gas (nitrogen, argon, or the like).

Note that an epoxy-based resin is preferably used for the sealant 1205. Moreover, it is desirable that these materials are materials that do not transmit moisture and oxygen as much as possible. In addition to a glass substrate or a quartz substrate, a plastic substrate made of FRP (Fiberglass-Reinforced Plastics), PVF (polyvinyl fluoride), polyester, acrylic, or the like can be used as a material for the sealing substrate 1204.

As described above, a light-emitting device can be obtained by applying one embodiment of the present invention. An active matrix light-emitting device is likely to have a high manufacturing cost per sheet because a TFT is manufactured; however, by applying one embodiment of the present invention, a material loss in forming a light-emitting element is significantly increased. It is possible to reduce. Therefore, the manufacturing cost can be reduced.

In addition, by applying one embodiment of the present invention, an EL layer included in the light-emitting element can be easily formed, and a light-emitting device including the light-emitting element can be easily manufactured. In addition, since a flat and uniform film can be formed and a fine pattern can be formed, a high-definition light-emitting device can be obtained. Further, since a lamp heater or the like having a large amount of heat can be used as a light source during film formation, the tact time can be shortened, and the manufacturing cost of the light emitting device can be reduced.

Note that the structure described in this embodiment can be combined with any of the structures described in Embodiments 1 to 4 as appropriate.

(Embodiment 6)
In this embodiment, examples of various electronic devices and lighting devices completed using the light-emitting device to which one embodiment of the present invention is applied will be described with reference to FIGS.

As electronic devices to which the light-emitting device is applied, for example, a television set (also referred to as a television or a television receiver), a monitor for a computer, a digital camera, a digital video camera, a digital photo frame, a mobile phone (a mobile phone, a mobile phone) Also referred to as a telephone device), portable game machines, portable information terminals, sound reproduction devices, large game machines such as pachinko machines, and the like. Specific examples of these electronic devices and lighting fixtures are shown in FIGS.

FIG. 8A illustrates an example of a television device 9100. In the television device 9100, a display portion 9103 is incorporated in a housing 9101. Images can be displayed on the display portion 9103, and a light-emitting device can be used for the display portion 9103. Here, a structure in which the housing 9101 is supported by a stand 9105 is shown.

The television device 9100 can be operated with an operation switch included in the housing 9101 or a separate remote controller 9110. Channels and volume can be operated with an operation key 9109 provided in the remote controller 9110, and an image displayed on the display portion 9103 can be operated. The remote controller 9110 may be provided with a display portion 9107 for displaying information output from the remote controller 9110.

Note that the television set 9100 is provided with a receiver, a modem, and the like. General TV broadcasts can be received by a receiver, and connected to a wired or wireless communication network via a modem, so that it can be unidirectional (sender to receiver) or bidirectional (sender and receiver). It is also possible to perform information communication between each other or between recipients).

FIG. 8B illustrates a computer, which includes a main body 9201, a housing 9202, a display portion 9203, a keyboard 9204, an external connection port 9205, a mouse 9206, and the like. Note that the computer is manufactured by using the light-emitting device for the display portion 9203.

FIG. 8C illustrates a portable game machine, which includes two housings, a housing 9301 and a housing 9302, which are connected with a joint portion 9303 so that the portable game machine can be opened or folded. A display portion 9304 is incorporated in the housing 9301 and a display portion 9305 is incorporated in the housing 9302. In addition, the portable game machine shown in FIG. 8C includes a speaker portion 9306, a recording medium insertion portion 9307, an LED lamp 9308, input means (operation keys 9309, a connection terminal 9310, a sensor 9311 (force, displacement, position). , Speed, acceleration, angular velocity, number of revolutions, distance, light, liquid, magnetism, temperature, chemical, sound, time, hardness, electric field, current, voltage, power, radiation, flow rate, humidity, gradient, vibration, smell or infrared A microphone 9312) and the like. Needless to say, the structure of the portable game machine is not limited to the above, and a light-emitting device may be used at least for one or both of the display portion 9304 and the display portion 9305, and other accessory facilities may be provided as appropriate. can do. The portable game machine shown in FIG. 8C shares the information by reading a program or data recorded in a recording medium and displaying the program or data on a display unit, or by performing wireless communication with another portable game machine. It has a function. Note that the function of the portable game machine illustrated in FIG. 8C is not limited to this, and the portable game machine can have a variety of functions.

FIG. 8D illustrates a desk lamp, which includes a lighting portion 9401, an umbrella 9402, a variable arm 9403, a column 9404, a base 9405, and a power source 9406. Note that the desk lamp is manufactured by using a light-emitting device for the lighting portion 9401. The lighting fixture includes a ceiling-fixed lighting fixture or a wall-mounted lighting fixture.

FIG. 8E illustrates an example of a mobile phone. A mobile phone 9500 includes a display portion 9502 incorporated in a housing 9501, operation buttons 9503, an external connection port 9504, a speaker 9505, a microphone 9506, and the like. Note that the cellular phone 9500 is manufactured using the light-emitting device for the display portion 9502.

A cellular phone 9500 illustrated in FIG. 8E can input information by touching the display portion 9502 with a finger or the like. In addition, operations such as making a call or typing an e-mail can be performed by touching the display portion 9502 with a finger or the like.

There are mainly three screen modes of the display portion 9502. The first mode is a display mode mainly for displaying an image. The first is a display mode mainly for displaying images, and the second is an input mode mainly for inputting information such as characters. The third is a display + input mode in which the display mode and the input mode are mixed.

For example, when making a phone call or creating an e-mail, the display unit 9502 may be set to a character input mode mainly for inputting characters and an operation for inputting characters displayed on the screen may be performed. In this case, it is preferable to display a keyboard or number buttons on most of the screen of the display portion 9502.

In addition, the mobile phone 9500 is provided with a detection device having a sensor for detecting inclination, such as a gyroscope or an acceleration sensor, so that the orientation (vertical or horizontal) of the mobile phone 9500 can be determined and the screen display of the display portion 9502 can be performed. Can be switched automatically.

Further, the screen mode is switched by touching the display portion 9502 or operating the operation button 9503 of the housing 9501. Further, switching can be performed depending on the type of image displayed on the display portion 9502. For example, if the image signal to be displayed on the display unit is moving image data, the mode is switched to the display mode, and if it is text data, the mode is switched to the input mode.

Further, in the input mode, when a signal detected by the optical sensor of the display portion 9502 is detected and there is no input by a touch operation on the display portion 9502 for a certain period, the screen mode is switched from the input mode to the display mode. You may control.

The display portion 9502 can also function as an image sensor. For example, personal authentication can be performed by touching the display portion 9502 with a palm or a finger to capture an image of a palm print, a fingerprint, or the like. In addition, if a backlight that emits near-infrared light or a sensing light source that emits near-infrared light is used for the display portion, finger veins, palm veins, and the like can be imaged.

As described above, an electronic device or a lighting fixture can be obtained by using the light-emitting device of one embodiment of the present invention. The application range of the light-emitting device of one embodiment of the present invention is so wide that the light-emitting device can be applied to electronic devices in various fields.

Note that the structure described in this embodiment can be combined with any of the structures described in Embodiments 1 to 5 as appropriate.

In this example, an example of an EL layer formed using the film formation method of one embodiment of the present invention will be described. Note that structural formulas of substances used in this example are shown below.

The production methods of the configuration examples 1 and 2 and the comparative examples 1 and 2 of the EL layer produced in this example are shown below.

(Configuration example 1)
A glass substrate was used as the first substrate which is a support substrate. On the first substrate, a Ti film having a thickness of 150 nm was formed as an absorption layer.

Further, a first material layer was formed on the absorption layer by a wet method. The first material layer includes a first film formation material, a second film formation material, and a polymer compound. 9,10-diphenyl-2- [N-phenyl-N- (9-phenyl-9H-carbazol-3-yl) amino] anthracene (abbreviation: 2PCAPA) was used as the first film formation material. 9- [4- (N-carbazolyl) phenyl] -10-phenylanthracene (abbreviation: CzPA) was used as the second film formation material. Further, poly (N-vinylcarbazole) (abbreviation: PVK) was used as a polymer compound, and these materials were dissolved in toluene used as a solvent. The weight ratio of toluene, PVK, CzPA and 2PCAPA was adjusted to 150: 5: 1: 0.05 (= toluene: PVK: CzPA: 2PCAPA). The thickness of the first material layer was 150 nm. In addition, the sublimation temperature of CzPA at the time of a vacuum (vacuum degree 10 < ^-3 > Pa) is 210 degreeC, and the sublimation temperature of 2PCAPA is 260 degreeC. The glass transition temperature of PVK is 200 ° C.

After the first material layer was formed, heat treatment was performed in a vacuum atmosphere in order to remove toluene remaining in the first material layer. Specifically, it was heated at a vacuum degree of 1 Pa and 160 ° C. for 1 hour.

Next, a second substrate, which is a deposition target substrate, was disposed on the support substrate at a position facing the surface on which the absorption layer and the first material layer were formed. A glass substrate was used as the second substrate. At this time, the distance d between the surface of the first material layer and the surface of the deposition target substrate was set to 100 μm. In addition, film formation by light irradiation is preferably performed in a reduced pressure atmosphere. Therefore, the degree of vacuum in the film formation chamber was kept at 5 × 10 ⁻³ Pa or less. Then, the first material layer is heated by irradiating the halogen lamp for 9 seconds from the back surface of the film formation substrate, that is, the other surface side of the film formation substrate on which the first material layer is formed. An EL layer was formed on the film substrate.

(Configuration example 2)
A high molecular compound used for the first material layer was prepared in the same manner as in Structural Example 1 except that a cycloolefin polymer having a glass transition temperature of 285 ° C. was used. That is, the first material layer includes CzPA as the first film formation material, 2PCAPA as the second film formation material, a cycloolefin polymer having a glass transition temperature of 285 ° C. as the polymer compound, and toluene as the solvent. The film thickness of the first material layer is 150 nm, and the ratio of toluene, cycloolefin polymer, CzPA and 2PCAPA in the first material layer is 150: 5: 1: 0.05 (= toluene: cycloolefin). Polymer: CzPA: 2PCAPA).

(Comparative Example 1)
An EL layer was formed on a glass substrate as a deposition target substrate by co-evaporation of CzPA and 2PCAPA using a vacuum deposition method. At this time, the degree of vacuum was maintained at 5 × 10 ⁻³ Pa or less in the film formation chamber. The film thickness of the EL layer was 30 nm, and the ratio of CzPA to 2PCAPA in the EL layer was adjusted to be 1: 0.05 (= CzPA: 2PCAPA) by weight. Note that co-evaporation is an evaporation method in which a plurality of different substances are simultaneously evaporated from different evaporation sources.

(Comparative Example 2)
A glass substrate was used as the first substrate which is a support substrate. On the first substrate, a Ti film having a thickness of 150 nm was formed as an absorption layer.

Furthermore, the first material layer was formed on the absorption layer by co-evaporation of CzPA and 2PCAPA using a vacuum deposition method. At this time, the degree of vacuum was maintained at 5 × 10 ⁻³ Pa or less in the film formation chamber. The film thickness of the EL layer was 30 nm, and the ratio of CzPA to 2PCAPA in the EL layer was adjusted to be 1: 0.05 (= CzPA: 2PCAPA) by weight.

Next, a second substrate, which is a deposition target substrate, was disposed on the support substrate at a position facing the surface on which the absorption layer and the first material layer were formed. A glass substrate was used as the second substrate. At this time, the distance d between the surface of the first material layer and the surface of the deposition target substrate was set to 100 μm. Further, the degree of vacuum in the film formation chamber was kept at 5 × 10 ⁻³ Pa or less. Then, CzPA and 2PCAPA are heated by irradiating a halogen lamp for 7 seconds from the back surface of the film formation substrate, that is, the other surface side of the film formation substrate on which the material layer is formed, and EL is formed on the film formation substrate. A layer was formed.

FIG. 9 shows photoluminescence (PL) spectra of Configuration Example 1, Comparative Example 1, and Comparative Example 2. FIG. 13 shows PL spectra of Configuration Example 2, Comparative Example 1, and Comparative Example 2. The PL spectrum is a spectrum that represents the wavelength and intensity of light emitted from the EL layer when irradiated with light having an excitation wavelength. 9 and 13, the horizontal axis represents wavelength (nm), and the vertical axis represents normalized PL intensity (arbitrary unit).

In this example, CzPA was used as the organic compound in which the luminescent material was dispersed, and 2PCAPA was used as the luminescent material. The sublimation temperature of CzPA during vacuum (degree of vacuum 10 ⁻³ Pa) is 210 ° C., and the sublimation temperature of 2PCAPA is 260 ° C. For this reason, if a time difference arises in raising the temperature from 210 ° C. to 260 ° C., CzPA sublimates first, and 2PCAPA sublimates later.

In FIG. 9, the PL spectrum of Comparative Example 2 has two peaks, a peak near 450 nm and a peak near 520 nm. In the process of raising the temperature of the first material layer by heat treatment, CzPA having a low sublimation temperature is transferred first, and 2PCAPA having a high sublimation temperature is transferred later. Therefore, since a concentration gradient is formed in the EL layer, two peaks are generated. That is, in the PL spectrum of Comparative Example 2, the peak near 450 nm is emitted by CzPA, and the peak near 520 nm is emitted by 2PCAPA. Note that in this embodiment, the transfer indicates that the first film formation material or the second film formation material included in the first material layer is transferred onto the deposition target substrate.

On the other hand, the PL spectra of Configuration Example 1 and Comparative Example 1 have one peak near 520 nm. Since Comparative Example 1 is formed by a vacuum deposition method, the PL spectrum of Comparative Example 1 has a light emission peak due to 2PCAPA. In Structural Example 1, PVK is contained in the first material layer, and even when the sublimation temperature of CzPA is reached, CzPA is not easily transferred from the first material layer. This is because PVK suppresses the movement of CzPA in the first material layer. Therefore, a time difference is hardly generated between the transfer of CzPA and the transfer of 2PCAPA, and a film having a small concentration gradient can be formed on the deposition target substrate. Therefore, in Configuration Example 1, light emission by CzPA is suppressed, and the PL spectrum of Configuration Example 1 has a peak of light emission by 2PCAPA.

In FIG. 13, the PL spectra of Comparative Example 1 and Configuration Example 2 have one peak in the vicinity of 520 nm. From Configuration Example 2, even when a cycloolefin polymer having a glass transition temperature of 285 ° C. is used as the polymer compound contained in the first material layer, a time difference is less likely to occur between CzPA transfer and 2PCAPA transfer, and the film has a small concentration gradient. It was shown that can be formed on a deposition target substrate. Therefore, in the configuration example 2, light emission by CzPA is suppressed, and the PL spectrum of the configuration example 2 has a peak of light emission by light emission by 2PCAPA.

Next, FIGS. 10 to 12 show data of ToF-SIMS (Time of Flight-Secondary Ion Mass Spectrometry). FIG. 10 shows ToF-SIMS data of Configuration Example 1, FIG. 11 shows Comparative Example 1, and FIG. 12 shows Comparative Example 2. This ToF-SIMS data is obtained by measuring the concentration distribution of the first film forming material and the second film forming material in the depth direction in the EL layer surface by cutting the sample obliquely. . 10 to 12, the horizontal axis represents the measurement position (μm), and the vertical axis represents the secondary ion intensity (counts / sec).

In FIG. 10, peaks of CzPA and 2PCAPA are seen inside the EL layer (region A). 10 to 12, in Configuration Example 1 and Comparative Example 1, it was shown that CzPA and 2PCAPA were mixed at a substantially constant concentration inside the EL layer (region A). On the other hand, in Comparative Example 2, the CzPA peak and the 2PCAPA peak are shifted, and the concentration of CzPA is high inside the EL layer (region A), and the concentration of 2PCAPA is high in region B which is the surface of the EL layer. Recognize. This means that CzPA having a lower sublimation temperature was transferred first, and 2PCAPA having a higher sublimation temperature was transferred later than CzPA.

If the organic compound that disperses the light-emitting substance and the light-emitting substance is separated as in Comparative Example 2, the EL characteristics such as the emission color are adversely affected. Since Configuration Example 1 includes PVK in the first material layer, as shown in FIG. 10, CzPA, which is an organic compound in which a luminescent material is dispersed, and 2PCAPA, which is a luminescent material, are in a better mixed state than Comparative Example 2 Can keep. Thereby, EL characteristics can be improved.

In this example, an example of an EL layer formed using the film formation method of one embodiment of the present invention will be described.
Note that structural formulas of substances used in this example are shown below.

Hereinafter, a manufacturing method of the configuration example 3 and the comparative examples 3 and 4 of the EL layer manufactured in this example will be described.

(Configuration example 3)
A glass substrate was used as the first substrate which is a support substrate. A titanium (Ti) film with a thickness of 150 nm was formed as an absorption layer over the first substrate.

Further, a first material layer was formed on the absorption layer by a wet method. The first material layer includes a first film formation material, a second film formation material, a third film formation material, and a polymer compound. As the first film forming material, (acetylacetonato) bis (2,3,5-triphenylpyrazinato) iridium (III) (abbreviation: Ir (tppr) ₂ (acac)) was used. 4,4′-bis [N- (1-naphthyl) -N-phenylamino] biphenyl (abbreviation: NPB) was used as the second film formation material. Bis (2-methyl-8-quinolinolato) (4-phenylphenolato) aluminum (abbreviation: BAlq) was used as the third film-forming material. Moreover, PVK was used as a polymer compound, and these materials were dissolved in chloroform used as a solvent. The ratio of chloroform, PVK, BAlq, NPB and Ir (tppr) ₂ (acac) is 200: 5: 1: 0.15: 0.06 by weight (= chloroform: PVK: BAlq: NPB: Ir (tppr) ₂ (acac)). The thickness of the first material layer was 150 nm. The sublimation temperature of BAlq in vacuum (vacuum degree 10 ⁻³ Pa) is 213 ° C., the sublimation temperature of NPB is 250 ° C., and the sublimation temperature of Ir (tppr) ₂ (acac) is 266 ° C.

After the first material layer was formed, heat treatment was performed in a vacuum atmosphere in order to remove chloroform remaining in the first material layer. Specifically, it was heated at a degree of vacuum of 0.2 Pa and 80 ° C. for 1 hour.

Next, a second substrate, which is a deposition target substrate, was disposed on the support substrate at a position facing the surface on which the absorption layer and the first material layer were formed. A glass substrate was used as the second substrate. At this time, the distance d between the surface of the first material layer and the surface of the second substrate was 100 μm. Further, the degree of vacuum in the film formation chamber was kept at 5 × 10 ⁻³ Pa or less. Then, BAlq, NPB, and Ir (tppr) ₂ (acac) are heated by irradiating a halogen lamp for 9 seconds from the back surface of the first substrate, that is, the other surface side of the deposition substrate on which the material layer is formed. Then, an EL layer was formed on the deposition target substrate.

(Comparative Example 3)
By using a vacuum evaporation method, BAlq, NPB, and Ir (tppr) ₂ (acac) were co-evaporated to form an EL layer on a glass substrate as a deposition substrate. At this time, the degree of vacuum was maintained at 5 × 10 ⁻³ Pa or less in the film forming chamber. The thickness of the EL layer is 30 nm, and the ratio of BAlq, NPB and Ir (tppr) ₂ (acac) in the EL layer is 1: 0.15: 0.06 (= BAlq: NPB: Ir (tppr) by weight ratio. ) ₂ (acac)).

(Comparative Example 4)
A glass substrate was used as the first substrate which is a support substrate. On the first substrate, a Ti film having a thickness of 150 nm was formed as an absorption layer.

Further, a first material layer was formed on the absorption layer by co-evaporating BAlq, NPB, and Ir (tppr) ₂ (acac) using a vacuum deposition method. At this time, the degree of vacuum was maintained at 5 × 10 ⁻³ Pa or less in the film formation chamber. The thickness of the EL layer is 30 nm, and the ratio of BAlq, NPB and Ir (tppr) ₂ (acac) in the EL layer is 1: 0.15: 0.06 (= BAlq: NPB: Ir (tppr)) ₂ (acac)).

Next, a second substrate, which is a deposition target substrate, was disposed on the support substrate at a position facing the surface on which the absorption layer and the first material layer were formed. A glass substrate was used as the second substrate. At this time, the distance d between the surface of the first material layer and the surface of the deposition target substrate was set to 100 μm. Further, the degree of vacuum in the film formation chamber was kept at 5 × 10 ⁻³ Pa or less. Then, BAlq, NPB, and Ir (tppr) ₂ (acac) are heated by irradiating a halogen lamp for 9 seconds from the back surface of the film formation substrate, that is, the other surface side of the film formation substrate on which the material layer is formed. Then, an EL layer was formed on the deposition target substrate.

FIG. 14 shows photoluminescence (PL) spectra of Configuration Example 3, Comparative Example 3, and Comparative Example 4. In FIG. 14, the horizontal axis represents wavelength (nm) and the vertical axis represents normalized PL intensity (arbitrary unit).

In this embodiment, BAlq is used as the organic compound in which the luminescent material is dispersed, and NPB and Ir (tppr) ₂ (acac) are used as the luminescent material. The sublimation temperature of BAlq in vacuum (vacuum degree 10 ⁻³ Pa) is 213 ° C., the sublimation temperature of NPB is 250 ° C., and the sublimation temperature of Ir (tppr) ₂ (acac) is 266 ° C. For this reason, when a time difference occurs in raising the temperature from 213 ° C. to 266 ° C., BAlq first sublimates, then NPB sublimates, and finally Ir (tppr) ₂ (acac) sublimates.

In FIG. 14, the PL spectrum of Comparative Example 4 has two peaks, a peak near 500 nm and a peak near 620 nm. In the process of raising the temperature of the first material layer by heat treatment, BAlq having a low sublimation temperature is transferred first, followed by NPB and finally Ir (tppr) ₂ (acac). Therefore, since a concentration gradient is formed in the EL layer, two peaks are generated. That is, in the PL spectrum of Comparative Example 2, the peak near 500 nm is light emission by BAlq and NPB, and the peak near 620 nm is light emission by Ir (tppr) ₂ (acac). Note that in this embodiment, transfer refers to transfer of the first film formation material, the second film formation material, or the third film formation material included in the first material layer onto the film formation substrate. Indicates.

On the other hand, the PL spectra of Configuration Example 3 and Comparative Example 3 have one peak near 620 nm. Since Comparative Example 3 is formed by a vacuum deposition method, the PL spectrum of Comparative Example 3 has a light emission peak due to Ir (tppr) ₂ (acac). In the configuration example 3, PVK is included in the first material layer, and even when the sublimation temperature of BAlq is reached, BAlq is hardly transferred from the first material layer. This is because BAlq is prevented from moving in the first material layer by PVK. Therefore, a time difference is hardly generated in the transfer of BAlq, NPB, and Ir (tppr) ₂ (acac), and a film with a small concentration gradient can be formed on the deposition target substrate. Therefore, in the configuration example 3, light emission by the BAlq and NPB is suppressed, and the PL spectrum of the configuration example 3 has a peak of light emission by Ir (tppr) ₂ (acac).

In this example, an example of an EL layer formed using the film formation method of one embodiment of the present invention will be described.
Note that structural formulas of substances used in this example are shown below.

The production methods of Structural Example 4 and Comparative Examples 5 to 7 of the EL layer produced in this example are shown below.

(Configuration example 4)
A glass substrate was used as the first substrate which is a support substrate. On the first substrate, a Ti film having a thickness of 150 nm was formed as an absorption layer.

Further, a first material layer was formed on the absorption layer. The first material layer includes a first film formation material, a second film formation material, and a polymer compound. As the first film formation material, 4- (10-phenyl-9-anthryl) -4 ′-(9-phenyl-9H-carbazol-3-yl) triphenylamine (abbreviation: PCBAPA) was used. CzPA was used as the second film forming material. In addition, a cycloolefin polymer having a glass transition temperature of 285 ° C. was used as the polymer compound, and these materials were dissolved in toluene used as a solvent. The weight ratio of toluene, PN285A, CzPA, and PCBAPA was adjusted to 150: 5: 1: 0.1 (= toluene: cycloolefin polymer: CzPA: PCBAPA). The thickness of the first material layer was 150 nm. The sublimation temperature of PCBAPA in a vacuum (degree of vacuum 10 ⁻³ Pa) is 302 ° C.

After the first material layer was formed, heat treatment was performed in a vacuum atmosphere in order to remove toluene remaining in the first material layer. Specifically, it was heated at a vacuum degree of 1 Pa and 160 ° C. for 1 hour.

Next, a second substrate, which is a deposition target substrate, was disposed on the support substrate at a position facing the surface on which the absorption layer and the first material layer were formed. A glass substrate was used as the second substrate. At this time, the distance d between the surface of the first material layer and the surface of the deposition target substrate was 100 μm. Further, the degree of vacuum in the film formation chamber was kept at 5 × 10 ⁻³ Pa or less. Then, the first material layer is heated by irradiating a halogen lamp for 9 seconds from the back surface of the first substrate, that is, the other surface side of the deposition substrate on which the first material layer is formed. An EL layer was formed on the film substrate.

(Comparative Example 5)
PVK was used instead of the cycloolefin polymer in Structural Example 4. That is, it was produced in the same manner as in Structural Example 4 except that PVK was used as the polymer compound contained in the first material layer.

(Comparative Example 6)
An EL layer was formed on a glass substrate as a deposition target substrate by co-evaporation of CzPA and PCBAPA using a vacuum deposition method. Further, the degree of vacuum was maintained at 5 × 10 ⁻³ Pa or less in the film forming chamber. The thickness of the EL layer was 30 nm, and the ratio of CzPA and PCBAPA in the EL layer was adjusted to be 1: 0.1 (= CzPA: PCBAPA) by weight.

(Comparative Example 7)
A glass substrate was used as the first substrate which is a support substrate. On the first substrate, a Ti film having a thickness of 150 nm was formed as an absorption layer.

Further, a first material layer was formed on the absorption layer by co-evaporation of CzPA and PCBAPA using a vacuum deposition method. At this time, the degree of vacuum was maintained at 5 × 10 ⁻³ Pa or less in the film formation chamber. The film thickness of the EL layer was 30 nm, and the ratio of CzPA and PCBAPA in the EL layer was adjusted to be 1: 0.1 (= CzPA: PCBAPA) by weight.

Next, a second substrate, which is a deposition target substrate, was disposed on the support substrate at a position facing the surface on which the absorption layer and the first material layer were formed. A glass substrate was used as the second substrate. At this time, the distance d between the surface of the first material layer and the surface of the deposition target substrate was set to 100 μm. Further, the degree of vacuum in the film formation chamber was kept at 5 × 10 ⁻³ Pa or less. Then, the first material layer is heated by irradiating the halogen lamp for 9 seconds from the back surface of the film formation substrate, that is, the other surface side of the film formation substrate on which the first material layer is formed. An EL layer was formed on the film substrate.

In FIG. 15, the photo-luminescence (PL) spectrum of Comparative Examples 5-7 is shown. FIG. 16 shows photoluminescence (PL) spectra of Configuration Example 4, Comparative Example 6, and Comparative Example 7. 15 and 16, the horizontal axis represents wavelength (nm), and the vertical axis represents normalized PL intensity (arbitrary unit).

In this embodiment, CzPA is used as the organic compound in which the luminescent material is dispersed, and PCBAPA is used as the luminescent material. The sublimation temperature of CzPA in a vacuum (degree of vacuum 10 ⁻³ Pa) is 210 ° C., and the sublimation temperature of PCBAPA is 302 ° C. For this reason, when a time difference occurs in raising the temperature from 210 ° C. to 302 ° C., CzPA is sublimated first and PCBAPA is sublimated later.

15 to 16, the PL spectrum of Comparative Example 6 has a peak near 460 nm. Since Comparative Example 6 is formed by a vacuum deposition method, the PL spectrum of Comparative Example 6 has a light emission peak due to PCBAPA.

On the other hand, in FIGS. 15 to 16, in the PL spectra of Comparative Example 5 and Comparative Example 7, a peak occurs in the vicinity of 450 nm. In the PL spectrum of Comparative Example 7, CzPA having a low sublimation temperature is transferred first, and PCBAPA is transferred later, in the process of raising the temperature of the first material layer by heat treatment. Therefore, the EL layer has a concentration gradient, and has a peak in which light emission by CzPA and light emission by PCBAPA overlap.

In Comparative Example 5, the glass transition temperature of PVK is lower by 100 ° C. or more than the sublimation temperature of PCBAPA. Accordingly, PVK is sufficiently softened before reaching the PCBAPA sublimation temperature of 302 ° C., so that CzPA can move in the first material layer. As a result, CzPA is first transferred onto the deposition target substrate. Therefore, Comparative Example 5 has a concentration gradient in the EL layer, and the PL spectrum of Comparative Example 5 has a peak in which light emission by CzPA and light emission by PCBAPA overlap. Note that in this embodiment, the transfer indicates that the first film formation material or the second film formation material included in the first material layer is transferred onto the deposition target substrate.

In FIG. 16, the PL spectrum of Configuration Example 4 has a peak in the vicinity of 460 nm. In Configuration Example 4, the first material layer includes a cycloolefin polymer having a glass transition temperature of 285 ° C., and even when the sublimation temperature of CzPA is reached, CzPA is hardly transferred from the first material layer. This is because the cycloolefin polymer suppresses the movement of CzPA in the first material layer. Therefore, a time difference is hardly generated between the transfer of CzPA and the transfer of PCBAPA, and a film having a small concentration gradient can be formed on the deposition target substrate. Therefore, in the configuration example 4, light emission by CzPA is suppressed, and the PL spectrum of the configuration example 1 has a peak of light emission by PCBAPA.

101 first substrate 103 absorption layer 105 first material layer 105a first film formation material 105b second film formation material 107 second substrate 109 second material layer 301 first substrate 302 reflection layer 303 absorption layer 304 heat insulating layer 305 first material layer 306 protective layer 307 second substrate 308 electrode layer 309 second material layer 310 light 311 insulator 312 opening 401 reflecting layer 402 opening 411 EL layer (R)
412 EL layer (G)
413 EL layer (B)
414 Insulator 901 Substrate 902 First electrode 903 EL layer 904 Second electrode 911 Hole injection layer 912 Hole transport layer 913 Light-emitting layer 914 Electron transport layer 915 Electron injection layer 1001 Substrate 1004 Insulation layer 1013 First electrode 1014 Partition 1016 Second electrode 1021 Light emitting region 1022 Partition 1102 Data line 1103 Scanning line 1104 Partition 1105 Region 1106 Input terminal 1107 Input terminal 1108 Connection wiring 1109a FPC
1109b FPC
1200 EL layer 1201 Drive circuit section (source side drive circuit)
1202 Pixel portion 1203 Drive circuit portion (gate side drive circuit)
1204 Sealing substrate 1205 Sealing material 1207 Space 1208 Wiring 1209 FPC
1210 Element substrate 1211 Switching TFT
1212 Current control TFT
1213 1st electrode 1214 Insulator 1215 Light emitting element 1216 2nd electrode 1223 n-channel TFT
1224 p-channel TFT
9100 Television apparatus 9101 Case 9103 Display unit 9105 Stand 9107 Display unit 9109 Operation key 9110 Remote controller 9201 Main unit 9202 Case 9203 Display unit 9204 Keyboard 9205 External connection port 9206 Mouse 9301 Case 9302 Case 9303 Connection unit 9304 Display unit 9305 Display unit 9306 Speaker unit 9307 Recording medium insertion unit 9308 LED lamp 9309 Operation key 9310 Connection terminal 9311 Sensor 9312 Microphone 9401 Illumination unit 9402 Umbrella 9403 Variable arm 9404 Post 9405 Base 9406 Power supply 9500 Mobile phone 9501 Case 9502 Display unit 9503 Operation button 9504 External connection port 9505 Speaker 9506 Microphone

Claims (12)

An absorption layer formed on one surface of the substrate, and a material layer formed on the absorption layer, the first film formation material, the second film formation material, and a polymer compound satisfying the following mathematical formula (1) One side of the first substrate having:
Arrange the second substrate to face the deposition surface,
By heat-treating the material layer from the other surface side of the first substrate, the first film-forming material and the second film-forming material are formed on the film-forming surface of the second substrate. The film-forming method which forms the layer containing this.
(In the formula (1), S represents the glass transition temperature (℃) of the polymer compound, T _a is the first film-forming material or a higher temperature of the sublimation temperature with the second film-forming material (℃) Indicate) In claim 1,
The film formation method in which the absorption layer is formed in an island shape or a stripe shape. In claim 2,
The film forming method wherein the material layer is formed in an island shape or a stripe shape. In claim 1 or claim 3,
A film forming method in which a reflective layer having an opening is formed between the first substrate and the absorbing layer. In claim 4,
The film-forming method which forms the heat insulation layer which has an opening part in the position which overlaps with the opening part of the said reflection layer between the said reflection layer and the said absorption layer. In any one of Claims 1 thru | or 7,
A film forming method in which a protective layer is formed between the absorption layer and the material layer. In any one of Claims 1 thru | or 6,
A film forming method using a cycloolefin polymer as the polymer compound. In any one of Claims 1 thru | or 7,
The material layer is formed on the absorbing layer by vapor deposition, sputtering, spin coating, printing, droplet ejection, spraying, dropping, inkjet, nozzle printing, or dispensing. . In any one of Claims 1 thru | or 8,
The heat treatment is a film formation method using a method in which light is irradiated from the other surface side of the first substrate using a light source, and the absorption layer is heated by absorbing light. In claim 9,
A film forming method using a laser oscillation device, a flash lamp or a halogen lamp as the light source.   A light-emitting element manufactured using the film formation method according to claim 1.   A light-emitting device having the light-emitting element according to claim 11.