JP2011060592A - Organic el element, display panel, and method of manufacturing display panel - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an organic electroluminescent (EL) element suppressing a view-angle dependence of a top-emission type organic EL element, and to provide a method of manufacturing the same. <P>SOLUTION: The organic EL element includes a first electrode, a second electrode opposed to the first electrode, barrier ribs dividing the first electrode for each pixel, and a light emission medium layer sandwiched between the first electrode and the second electrode containing at least an organic luminescent layer and a carrier injection layer formed between the first electrode and the organic luminescent layer on a substrate. In the organic EL element and a display panel, the pixels include at least a first pixel giving a first luminescent color and a second pixel giving a second luminescent color, and the first electrode of the first pixel has the first pattern, of which, the film thickness distribution varies in multi-steps, while, the first electrode of the second pixel has the second pattern, of which, the film thickness distribution varies in multi-steps different from that of the first pattern. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an organic EL element structure using an organic thin film electroluminescence (hereinafter abbreviated as EL) phenomenon and a method for manufacturing the organic EL element.

  In recent years, a drive type color organic EL display panel using a thin film transistor (TFT) has been devised. In the display panel, the so-called bottom emission method, in which light is extracted to the substrate side on which the TFT is formed, does not increase the aperture ratio due to the light shielding effect of the wiring portion. A top emission method, which is a method of extracting light on the opposite side, has been devised.

However, when the top emission method is adopted, the optical path length passing through each layer is wider before the light emitted from the organic light emitting layer is extracted than the bottom emission method. Effect), the viewing angle dependency appears.
Further, the dependency has a problem that the characteristics change depending on the thickness of the electrode and the thickness of the organic EL layer.

  As a technique for suppressing the viewing angle dependency, Patent Document 1 discloses a method for suppressing the viewing angle dependency by randomly changing the ITO film thickness. This method is a white color in a bottom emission type organic EL element. It is considered that the same characteristics cannot be obtained with a top emission type single color. That is, the conventional top emission type organic EL element and display panel have a problem that the light emitted from the organic light emitting layer has a viewing angle dependency due to a multiple reflection effect (cavity effect).

JP 2004-281080 A JP 2004-335470 A

  An object of the present invention is to provide an organic EL element and a method for manufacturing the same, in which the viewing angle dependency of the top emission type organic EL element is suppressed.

In order to solve the above problems, the invention of claim 1 includes a first electrode on a substrate,
A second electrode facing the first electrode;
A partition partitioning the first electrode for each pixel;
Sandwiched between the first electrode and the second electrode, at least an organic light emitting layer;
In an organic EL element having a light emitting medium layer including a carrier injection layer formed between a first electrode and an organic light emitting layer, and a display panel,
A first pixel that exhibits at least a first emission color;
Having a second pixel exhibiting a second emission color;
The first electrode of the first pixel has a first pattern having a film thickness distribution that changes in multiple stages, and the first electrode of the second pixel has a film that changes in multiple stages different from the first pattern. An organic EL device having a second pattern having a thickness distribution.

  According to a second aspect of the present invention, in the organic EL device according to the first aspect, the first electrode is formed of a reflective electrode made of a metal and performing specular reflection, and a transparent electrode on the reflective electrode. is there.

  In the invention according to claim 3, the carrier injection layer is formed of a hole transport layer and / or a hole injection layer, and an electron transport layer is provided between the second electrode and the organic light emitting layer. 2. The organic EL device according to claim 1, wherein an electron injection layer is formed.

According to a fourth aspect of the present invention, there is provided a display panel using the organic EL element according to any one of the first to third aspects.

The invention of claim 5 is a film forming step of forming a first electrode on a substrate;
A patterning step of patterning a film formed according to a pixel to be formed to form an electrode;
An etching process in which electrodes are formed in multiple stages for each pixel to form a first electrode, a partition is formed so as to cover an end of the patterned first electrode, and the first electrode A light emitting medium layer forming step of forming a light emitting medium layer so as to cover,
An electrode forming step of forming a second electrode so as to cover the organic EL layer;
It is a manufacturing method of the organic EL element characterized by comprising.

  The invention according to claim 6 is the method for producing an organic EL element according to claim 5, wherein at least one of the hole transport layer and the hole injection layer is formed by a wet process method. .

  The invention according to claim 7 is the method for producing an organic EL element according to claim 5, wherein at least one of the electron transport layer and the electron injection layer is formed by a wet process method.

  The invention according to claim 8 is the method for producing an organic EL element according to claim 6 or 7, wherein the wet process method is a relief printing method.

  The invention according to claim 9 is the method for producing an organic EL element according to any one of claims 5 to 8, wherein the light emitting medium layer is formed by a dry process method.

  The invention of claim 10 is a method for manufacturing an organic EL display panel, characterized in that the method for manufacturing an organic EL element according to any one of claims 5 to 9 is used.

  In the organic EL element and the manufacturing method thereof according to the present invention, the first electrode is formed in a three-dimensional film thickness in accordance with the organic film thickness and emission color, so that it depends on the viewing angle for each pixel. Sex can be suppressed.

It is a schematic sectional drawing of the conventional organic EL element. It is a schematic sectional drawing of the organic EL element of this invention. Schematic sectional view showing the element structure of the display panel Schematic diagram of letterpress printer Viewing angle characteristics of a comparative example in a conventional structure Viewing angle characteristics of embodiments in the structure of the present invention

In order to describe the organic EL display panel of the present invention, an active matrix driving type organic EL display panel will be described as an example. However, the present invention is not limited to the active matrix driving type organic EL display panel, and can also be applied to a passive matrix driving type organic EL display device.
Hereinafter, an organic EL device according to the present invention and a manufacturing method thereof will be described with reference to the drawings.

A schematic cross-sectional view of an organic EL element as one embodiment of the present invention is shown in FIG. The organic EL device of the present invention is sandwiched between a substrate 101, a first electrode (anode) 104 provided for each pixel on the substrate, and a second electrode (cathode) 110 formed so as to face the substrate. Layer (the light emitting medium layer 109).
The first electrode 104 is patterned on one surface of the substrate 101 according to the pixel to be formed. And the upper surface of each 1st electrode 104 is etched and formed in the multistep film thickness.
Further, the light emitting medium layer 109 includes at least an organic light emitting layer 108 that contributes to light emission and a hole transport layer 106 as a carrier injection layer for injecting electrons or holes. The light emitting medium layer 109 includes an electron injection layer or a hole blocking layer (interlayer 107) between the second electrode (cathode) 110 and the light emitting medium layer 109, and the first electrode (anode) 104 and the light emitting medium layer 109. A hole injection layer, an electron block layer (interlayer 107), and the like can be laminated between the layers as necessary.

  Furthermore, the organic EL element of the present invention has a partition wall 105 that partitions the organic light emitting layer 108. By arranging such organic EL elements as pixels (subpixels), a display panel can be obtained. A full-color display panel can be manufactured by coating the organic light-emitting layer 108 constituting each pixel with, for example, three colors of RGB.

  In the organic EL element of the present invention, the first electrode 104 is etched to form a multi-stage film thickness for each pixel in accordance with the light emission color and the film thickness of the light emitting medium. The characteristics can be improved and the viewing angle dependency can be suppressed.

  Hereinafter, the structure of the organic EL device of the present invention will be described in detail.

  FIG. 3 shows an example of a TFT substrate with a partition which can be used in the present invention. A substrate with a TFT (back plane) 310 used in the active matrix driving type organic EL display panel of the present invention is provided with a thin film transistor (TFT) and a lower electrode (pixel electrode) of the organic EL display panel, and the TFT and the lower portion. The electrode is electrically connected.

  The TFT and the active matrix driving type organic EL display panel formed thereon are supported by a support. Any material can be used as the support as long as it has mechanical strength and insulation and is excellent in dimensional stability. For example, plastic films and sheets such as glass, quartz, polypropylene, polyethersulfone, polycarbonate, cycloolefin polymer, polyarylate, polyamide, polymethyl methacrylate, polyethylene terephthalate, polyethylene naphthalate, etc., or oxidation to these plastic films and sheets Metal oxides such as silicon and aluminum oxide, metal fluorides such as aluminum fluoride and magnesium fluoride, metal nitrides such as silicon nitride and aluminum nitride, metal oxynitrides such as silicon oxynitride, acrylic resins and epoxy resins Translucent base materials in which a single layer or a plurality of layers of polymer resin films such as silicone resin and polyester resin are laminated, metal foils such as aluminum and stainless steel, sheets and plates, and the plastic films and sheets Aluminum, may be used copper, nickel, stainless steel and metal film non-translucent substrate as a laminate of such. What is necessary is just to select the translucency of a support body according to which surface takes out light. The support made of these materials has been subjected to moisture-proofing treatment or hydrophobic treatment by forming an inorganic film or applying a fluororesin in order to avoid intrusion of moisture into the organic EL display panel. It is preferable. In particular, it is preferable to reduce the moisture content and gas permeability coefficient of the support in order to prevent moisture from entering the luminescent medium layer.

  As the thin film transistor provided on the support, a known thin film transistor can be used. Specifically, a thin film transistor mainly including an active layer in which a source / drain region and a channel region are formed, a gate insulating film, and a gate electrode can be given. The structure of the thin film transistor is not particularly limited, and examples thereof include a staggered type, an inverted staggered type, a top gate type, and a coplanar type.

The active layer 303 is not particularly limited, and examples thereof include inorganic semiconductor materials such as amorphous silicon, polycrystalline silicon, microcrystalline silicon, cadmium selenide, thiophene oligomers, poly (p-ferylene vinylene), and the like. The organic semiconductor material can be used. These active layers 303 are formed by, for example, laminating amorphous silicon by plasma CVD, ion doping, forming amorphous silicon by LPCVD using SiH ₄ gas, and crystallizing amorphous silicon by solid phase growth. After obtaining polysilicon, ion doping is performed by ion implantation, amorphous silicon is formed by LPCVD using Si ₂ H ₆ gas, and PECVD using SiH ₄ gas, and laser such as excimer laser After annealing, the amorphous silicon is crystallized to obtain polysilicon, followed by ion doping (low-temperature process), low-pressure CVD or LPCVD, and polysilicon is thermally oxidized at 1000 ° C or higher. T The gate insulating film is formed, a gate electrode 8 of the n ⁺ polysilicon is formed thereon, then, the ion doping methods (high temperature process) by an ion implantation method, and the like.

As the gate insulating film 304, a well-known gate insulating film can be used. For example, SiO ₂ formed by PECVD method, LPCVD method, etc., or a polysilicon film is thermally oxidized. The obtained SiO ₂ or the like can be used.

  As the gate electrode 305, a well-known gate electrode can be used. For example, a metal such as aluminum or copper, a refractory metal (titanium, tantalum, tungsten, etc.), polysilicon, or a high melting point. Examples thereof include metal silicide and polycide.

  The thin film transistor may have a single gate structure, a double gate structure, or a multi-gate structure having three or more gate electrodes. Moreover, you may have a LDD structure and an offset structure. Further, two or more thin film transistors may be arranged in one pixel.

  The display panel of the present invention needs to be connected so that the thin film transistor functions as a switching element of the organic EL display panel, and the drain electrode 310 of the transistor and the pixel electrode of the organic EL display panel are electrically connected.

Next, a method for forming the first electrode 104 will be described.
A material to be the first electrode 104 is formed on the support (substrate) 101, and patterning is performed according to the pixel to be formed.
As a material for the first electrode 104, a material having a high work function is used in order to efficiently inject holes. In particular, in an ordinary organic EL element, since light is emitted through the anode, the anode is required to be transparent, and a conductive metal oxide such as ITO is used.
The top emission method of the present invention does not need to be transparent, but the first electrode 104 may be formed using a conductive metal oxide such as ITO or IZO. Further, when a conductive metal oxide such as ITO is used, it is preferable to use a reflective electrode (Cr, Al, Ag, Mo, W, etc.) having a high reflectance underneath. Since the reflective electrode 102 has a lower resistivity than the conductive metal oxide, it functions as an auxiliary electrode, and at the same time, the light emitted from the organic light emitting layer 108 is reflected toward the second electrode 110 so as to effectively use the light. It becomes possible.

  As the formation method of the first electrode 104, depending on the material, a dry film forming method such as a resistance heating vapor deposition method, an electron beam vapor deposition method, a reactive vapor deposition method, an ion plating method, a sputtering method, a gravure printing method, a screen A wet film forming method such as a printing method can be used. As a patterning method for the first electrode 104, an existing patterning method such as a mask vapor deposition method, a photolithography method, a wet etching method, or a dry etching method can be used depending on a material or a film forming method. In the case where a substrate on which a TFT is formed is used as the substrate, it is formed so as to be conductive corresponding to the lower pixel.

In the present invention, the first electrode 104 having the shape as shown in FIG. 2 is formed by patterning the reflective electrode 102 for each pixel by mask vapor deposition, and then forming the transparent electrode by the mask sputtering method. A film is formed on 102. Next, after forming a resist film and performing patterning to form a necessary pattern, anisotropic dry etching is performed.
By repeating the formation of the resist pattern and the dry etching process, it is possible to form an electrode having a multi-stage film thickness.

  The partition wall 105 of the present invention is preferably formed so as to partition a light emitting region corresponding to a pixel and cover an end portion of the first electrode 104 (see FIG. 2). In general, in an active matrix drive type display panel, a pixel electrode 104 is formed for each pixel (subpixel), and each pixel attempts to occupy as large an area as possible, so that the end of the pixel electrode is covered. The most preferable shape of the partition wall to be formed is basically a lattice shape that divides each pixel electrode by the shortest distance.

  As a method of forming the partition wall 105, as in the conventional case, an inorganic film is uniformly formed on a substrate, masked with a resist pattern, and then dry etching is performed, or a photosensitive resin is laminated on the substrate, and a photolithography method is performed. The method of setting to a predetermined pattern is mentioned. If necessary, a water repellent can be added, or plasma or UV can be irradiated to impart liquid repellency to the ink after formation. A preferable height of the partition wall 105 is 0.1 μm to 10 μm, and more preferably about 0.5 μm to 2 μm. If it is too high, the formation and sealing of the counter electrode will be hindered, and if it is too low, the end of the pixel electrode 301 will not be covered, or the adjacent pixels will be mixed when the light emitting medium layer 109 is formed.

Next, a method for forming the light emitting medium layer 109 such as the organic light emitting layer 108 will be described.
First, after the partition wall 105 is formed, the hole transport layer 106 is formed.
As hole transport materials, polyaniline derivatives, polythiophene derivatives, polyvinylcarbazole (PVK) derivatives, poly (3,4-ethylenedioxythiophene) (PEDOT)
Etc. These materials are dissolved or dispersed in a solvent, and are formed using various coating methods using a spin coater or the like, and a relief printing method. When an inorganic material is used as the hole transport material, examples of the inorganic material include Cu ₂ O, Cr ₂ O ₃ , Mn ₂ O ₃ , FeO _x ( _{x to} 0.1), NiO, CoO, Pr ₂ O ₃ , Inorganic materials such as Ag ₂ O, MoO ₂ , Bi ₂ O ₃ , ZnO, TiO ₂ , SnO ₂ , ThO ₂ , V ₂ O ₅ , Nb ₂ O ₅ , Ta ₂ O ₅ MoO ₃ , WO ₃ and MnO ₂ are used. It forms using a vapor deposition method. However, the material is not limited to these.

After the formation of the hole transport layer 106, the materials used for the interlayer layer 107 include aromatic substances such as polyvinyl carbazole or derivatives thereof, polyarylene derivatives having an aromatic amine in the side chain or main chain, arylamine derivatives, and triphenyldiamine derivatives. And polymers containing a group amine. These materials are dissolved or dispersed in a solvent, and are formed using various coating methods using a spin coater or the like, and a relief printing method.
After the formation of the interlayer layer 107, the organic light emitting layer 108 is formed. The organic light emitting layer 108 is a layer that emits light by passing an electric current. The organic light emitting material forming the organic light emitting layer 108 is, for example, a coumarin type, a perylene type, a pyran type, an anthrone type, a porphyrene type, a quinacridone type, N, N Dispersed luminescent dyes such as' -dialkyl-substituted quinacridone, naphthalimide, N, N'-diaryl-substituted pyrrolopyrrole, iridium complex in polymers such as polystyrene, polymethylmethacrylate, polyvinylcarbazole, etc. , Polyarylene-based, polyarylene vinylene-based, and polyfluorene-based polymer materials.

  These organic light emitting materials are dissolved or stably dispersed in a solvent to form an organic light emitting ink. Examples of the solvent for dissolving or dispersing the organic light emitting material include toluene, xylene, acetone, anisole, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, or a mixed solvent thereof. Among them, aromatic organic solvents such as toluene, xylene, and anisole are preferable from the viewpoint of the solubility of the organic light emitting material. Moreover, surfactant, antioxidant, a viscosity modifier, a ultraviolet absorber, etc. may be added to organic luminescent ink as needed.

Next, a relief printing apparatus according to an embodiment of the present invention will be described with reference to FIG.
FIG. 4 shows a case where an organic light-emitting ink made of an organic light-emitting material is used for pattern printing on a substrate to be printed 407 on which a pixel electrode, an insulating layer, and a hole transport layer are formed. 401, an ink chamber 402, an anilox roll 403, a plate copper 406 on which a plate 405 provided with a relief plate is mounted, and a stage 408 on which a substrate 407 to be printed is placed.
The ink tank 401 contains organic light-emitting ink diluted with a solvent, and the organic light-emitting ink is fed into the ink chamber 402 from the ink tank 401. The anilox roll 403 is instructed to rotate in contact with the ink supply unit of the ink chamber 401.

Next, the second electrode 110 is formed. When the second electrode is used as a cathode, a material having a high work function and high electron injection efficiency into the organic light emitting layer 108 is used. Specifically, it is a material such as LiF, BaF ₂ , CsF.
As the film formation method of the second electrode 110, a resistance heating method, an electron beam evaporation method, a reactive evaporation method, an ion plating method, or a sputtering method can be used depending on the material.

Next, a sealing body (not shown) will be described.
In order to extract display light emitted from the light emitting medium layer 109 through the sealing body on the side opposite to the substrate, light transmittance is required for the visible light wavelength region.
In addition, since the organic light emitting material is easily deteriorated by moisture and oxygen in the atmosphere, a sealing body (not shown) is usually provided for shielding from the outside. The sealing body can be manufactured, for example, by providing a resin layer on a sealing material.
The sealing material needs to be a base material having low moisture and oxygen permeability. Examples of the material include ceramics such as alumina, silicon nitride, and boron nitride, glass such as alkali-free glass and alkali glass, quartz, and moisture resistant film. Examples of moisture-resistant films include films formed by CVD of SiO _x on both sides of plastic substrates, films with low permeability and water-absorbing films, or polymer films coated with a water-absorbing agent. The water vapor permeability of the film is preferably 10 ⁻⁶ g / m ² / day or less.

  As an example of the material of the resin layer, a photo-curing adhesive resin, a thermosetting adhesive resin, a two-component curable adhesive resin made of epoxy resin, acrylic resin, silicon resin, or the like, or ethylene ethyl acrylate (EEA) ) Acrylic resins such as polymers, vinyl resins such as ethylene vinyl acetate (EVA), thermoplastic resins such as polyamide and synthetic rubber, and thermoplastic adhesive resins such as acid-modified products of polyethylene and polypropylene. . Examples of methods for forming a resin layer on a sealing material include solvent solution method, extrusion lamination method, melting / hot melt method, calendar method, nozzle coating method, screen printing method, vacuum laminating method, hot roll laminating method, etc. Can be mentioned. A material having a hygroscopic property or an oxygen absorbing property may be contained as necessary. Although the thickness of the resin layer formed on a sealing material is arbitrarily determined by the magnitude | size and shape of the organic electroluminescent display panel to seal, about 5-500 micrometers is desirable. In addition, although formed as a resin layer on the sealing material here, it can also be formed directly on the organic EL display panel side.

  Finally, the organic EL display panel and the sealing body are bonded together in a sealing chamber. When the sealing body has a two-layer structure of a sealing material and a resin layer, and a thermoplastic resin is used for the resin layer, it is preferable to perform only pressure bonding with a heated roll. When a thermosetting adhesive resin is used, it is preferable to perform heat curing at a curing temperature after pressure bonding with a heated roll. In the case where a photocurable adhesive resin is used, curing can be performed by further irradiating light after pressure bonding with a roll.

Before or instead of sealing with a sealing material, for example, as a passivation film, a dry process such as an EB vapor deposition method or a CVD method can be used to form a sealing body made of an inorganic thin film such as a silicon nitride film. It is also possible to combine these.
The thickness of the passivation film can be 100 to 500 nm, and 150 to 300 nm can be suitably used although it varies depending on the moisture permeability and water vapor light permeability of the material. In the top emission type structure, it is necessary to consider light transmittance in addition to the above characteristics, and it can be suitably used as long as it is 70% or more in the total average in the visible light wavelength region.

Next, examples of the present invention will be described.
<Example 1>
An active matrix substrate provided with a thin film transistor functioning as a switching element provided on a support as a substrate was used. The size of the substrate was 200 mm × 200 mm, and a 5-inch diagonal display was installed in the center, and the first electrode was formed above the substrate. As a forming method, first, Cr is mask-deposited as a reflective electrode, an ITO film is formed to a thickness of 150 nm by a sputtering method, and the film thickness is decreased from the end of the pixel toward the center by 10% of the pixel width. Then, when the light emitting layer is red, when 60 to 150 nm, blue and green, a mask is formed by sputtering film formation so as to have a multi-stage film thickness of 60 to 110 nm, and etching is performed by reactive ion etching Was repeated.

Next, partition walls were formed so as to partition the pixels.
The partition wall was formed by first spin coating an acrylic photoresist material to a thickness of 2 μm. A line pattern having a width of 40 μm was formed between the pixel electrodes by photolithography on the photoresist material applied to the front surface of the substrate.
A 20 nm-thick molybdenum oxide (MoO _x ) film was formed on the surfaces of the first electrode and the partition by a sputtering method.

  Next, this substrate was set in a relief printing machine using an ink in which a polyvinyl carbazole derivative, which is an interlayer material, was dissolved in toluene to a concentration of 0.5%, and the trueness of the first electrode sandwiched between insulating layers was set. The organic light emitting layer was printed by the relief printing method according to the line pattern. At this time, 300 lines / inch anilox roll and a water developing type photosensitive resin plate were used. The film thickness of the interlayer after printing and drying was 10 nm. Furthermore, using organic light-emitting ink in which polyphenylene vinylene derivative, which is an organic light-emitting material, is dissolved in toluene to a concentration of 1%, this substrate is set on a relief printing press, and the trueness of the first electrode sandwiched between insulating layers is set. The organic light emitting layer was printed by the relief printing method according to the line pattern. At this time, a 150 line / inch anilox roll and a water developing type photosensitive resin plate were used. The thickness of the organic light emitting layer after printing and drying was 80 nm. This process was repeated three times to form an organic light emitting layer for each pixel in R (red), G (green), and B (blue) emission colors.

Next, a Ba film was formed as a second electrode with a thickness of 4 nm by a vacuum evaporation method using a metal mask, and then an Al film was formed with a thickness of 5 nm using a metal mask by a vacuum evaporation method. Then, a SiO _x as a passivation film (not shown), and 200nm laminated by EB vapor deposition. Thereafter, sealing glass and an adhesive were placed so as to cover the light emitting region, and the adhesive was heat-cured at about 90 ° C. for 1 hour and hermetically sealed to produce an active matrix driving type organic EL panel.

<Comparative example>
Next, a comparative example will be described.
As a comparative example, an organic EL panel having a configuration not corresponding to the organic EL panel according to the present invention was produced. This comparative example is not the first electrode having a step formed in Example 1, but the first electrode after forming the first electrode patterned to have a film thickness of 150 nm over the entire width of the first electrode. A partition wall was formed so as to cover the buttocks. The steps prior to the formation of the first electrode were the same as those in Example 1. Therefore, an active matrix driving type organic EL display panel not corresponding to the present invention was produced because the hole transport layer had a substantially uniform film thickness and no film having higher resistance than the surroundings.
FIG. 5 shows the viewing angle characteristics of the comparative example, and FIG. 6 shows the viewing angle characteristics of the example.
The viewing angle characteristics of the examples are improved by improving the viewing angle characteristics and the light extraction efficiency depending on the film thickness, so that the viewing angle characteristics are improved as a whole, and the front (-30 to 30 degrees) luminance is improved as compared with the comparative example. Overall, the brightness was improved by 2%.

101 ... Support (substrate)
102 ... reflective electrode 103 ... transparent electrode 104 ... first electrode 105 ... partition 106 ... hole transport layer 107 ... interlayer layer 108 ... organic light emitting layer 109 ... Luminescent medium layer 110 ... second electrode 301 ... pixel electrode 302 ... support (substrate)
303 ... Active layer 304 ... Gate insulating film 305 ... Gate electrode 306 ... Source electrode 307 ... Drain electrode 308 ... Scan line 309 ... Insulating film 310 ... Substrate with TFT 311 ... partition 400 ... letterpress printing apparatus 401 ... ink tank 402 ... ink chamber 403 ... anilox roll 404 ... ink layer 405 ... plate 406 ... plate cylinder 407 ...・ Printed substrate 408... Stage

Claims (10)

A first electrode on the substrate;
A second electrode facing the first electrode;
A partition partitioning the first electrode for each pixel;
Sandwiched between the first electrode and the second electrode, at least an organic light emitting layer;
In an organic EL element having a light emitting medium layer including a carrier injection layer formed between a first electrode and an organic light emitting layer, and a display panel,
A first pixel that exhibits at least a first emission color;
Having a second pixel exhibiting a second emission color;
The first electrode of the first pixel has a first pattern having a film thickness distribution that changes in multiple stages, and the first electrode of the second pixel has a film that changes in multiple stages different from the first pattern. An organic EL element having a second pattern having a thickness distribution.   2. The organic EL element according to claim 1, wherein the first electrode is formed of a reflective electrode made of metal and performing specular reflection, and a transparent electrode on the reflective electrode.   The carrier injection layer is formed of a hole transport layer and / or a hole injection layer, and an electron transport layer and / or an electron injection layer is formed between the second electrode and the organic light emitting layer. The organic EL device according to claim 1, wherein   A display panel comprising the organic EL element according to claim 1. A film forming step for forming a first electrode on the substrate;
A patterning step of patterning a film formed according to a pixel to be formed to form an electrode;
An etching process in which electrodes are formed in multiple stages for each pixel to form a first electrode, a partition is formed so as to cover an end of the patterned first electrode, and the first electrode A light emitting medium layer forming step of forming a light emitting medium layer so as to cover,
An electrode forming step of forming a second electrode so as to cover the organic EL layer;
The manufacturing method of the organic EL element characterized by the above-mentioned.   6. The method of manufacturing an organic EL element according to claim 5, wherein at least one of the hole transport layer and the hole injection layer is formed by a wet process method.   6. The method of manufacturing an organic EL element according to claim 5, wherein at least one of the electron transport layer and the electron injection layer is formed by a wet process method.   The method for producing an organic EL element according to claim 6 or 7, wherein the wet process method is a relief printing method.   9. The method for manufacturing an organic EL element according to claim 5, wherein the light emitting medium layer is formed by a dry process method.   10. A method for producing an organic EL display panel, wherein the method for producing an organic EL element according to claim 5 is used.

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