WO2015178003A1 - Manufacturing method for light emitting device and light emitting device - Google Patents

Abstract

Provided is a manufacturing method for a light emitting device formed by disposing on a substrate a first light emitting element and a second light emitting element that have the same light emission color and that include: a first electrode and a second electrode one of which has light reflecting properties and the other of which has light transmitting properties; and, disposed between the first and second electrodes, a laminated structure of a plurality of functional layers which include a first layer and a second layer. In the manufacturing method, the first layer of the first light emitting element and the second light emitting element is formed by a sputtering method, and the second layer of the first light emitting element and the second light emitting element is formed by a coating method. If the optical film thickness of the first layer of the first light emitting element is Ds1, the optical film thickness of the first layer of the second light emitting element is Ds2, the optical film thickness of the second layer of the first light emitting element is Dw1, and the optical film thickness of the second layer of the second light emitting element is Dw2, the relationships Ds1<Ds2 and Dw1>Dw2 are satisfied.

Description

LIGHT EMITTING DEVICE MANUFACTURING METHOD AND LIGHT EMITTING DEVICE

The present invention relates to a method for manufacturing a light-emitting device and a light-emitting device, and particularly relates to suppression of luminance unevenness and chromaticity deviation.

In recent years, light-emitting devices such as organic EL (Electro-Luminescence) panels and organic EL lighting have been actively developed. Such a light emitting device generally has a configuration in which a plurality of functional layers including a light emitting layer are laminated between an anode and a cathode. Examples of the functional layer other than the light emitting layer include an electron injection layer and a hole transport layer. The light emitting device is required to improve the light emission efficiency, and the light emission efficiency is divided into an internal efficiency related to the photoelectric conversion rate of the organic light emitting material and an external efficiency related to the light extraction efficiency. As a method for improving the light extraction efficiency (external efficiency), a method of introducing a resonator structure in a light emitting device is conventionally known (for example, Patent Document 1 and Patent Document 2).

JP 2006-140130 A JP 2012-38555 A

The layers formed by sputtering may be included in the plurality of functional layers of the light emitting device. The layers formed by the sputtering method include a relatively thick portion and a relatively thin portion depending on factors such as the individuality of the device due to the arrangement of parts of the manufacturing device and the formation conditions of the functional layer. Occurs. When such a film thickness variation exists, the optical distance varies within the light emitting surface. Then, the resonance effect of the light also varies, which causes luminance unevenness and chromaticity deviation in the light emitting surface of the light emitting device.

The present invention has been made in view of the above problems, and a method for manufacturing a light-emitting device and a light-emitting device that can suppress unevenness in luminance and chromaticity deviation by suppressing variations in the resonance effect of light in the light-emitting surface. The purpose is to provide.

In the method for manufacturing a light-emitting device according to one embodiment of the present invention, a first light-emitting element and a second light-emitting element having the same emission color are arranged on a substrate, and both the first light-emitting element and the second light-emitting element are A plurality of first and second electrodes, one having light reflectivity and the other having light transmissivity, and disposed between the first electrode and the second electrode, and including a first layer and a second layer A method of manufacturing a light emitting device having a stacked structure of functional layers, wherein the first layer of the first light emitting element and the first layer of the second light emitting element are formed by sputtering, The second layer of one light emitting element and the second layer of the second light emitting element are formed by a coating method, and optical in a direction orthogonal to the main surface of the substrate of the first layer and the second layer Regarding the film thickness, the optical film thickness of the first layer in the first light-emitting element is Ds1, The optical film thickness of the first layer in the second light emitting element is Ds2, the optical film thickness of the second layer in the first light emitting element is Dw1, and the optical film thickness of the second layer in the second light emitting element. Is Dw2, the relation of Ds1 <Ds2 and Dw1> Dw2 is satisfied.

According to the method for manufacturing a light emitting device according to one embodiment of the present invention, the optical thickness Ds2 of the first layer in the second light emitting element is thicker than the optical thickness Ds1 of the first layer in the first light emitting element. On the other hand, the optical film thickness Dw2 of the second layer in the second light emitting element is thinner than the optical film thickness Dw1 of the second layer in the first light emitting element. That is, in the first light emitting element, the relatively thin optical film thickness Ds1 of the first layer can be offset by the relatively thick optical film thickness Dw1 of the second layer. Similarly, in the second light emitting element, the relatively thick optical film thickness Ds2 of the first layer can be offset by the relatively thin optical film thickness Dw2 of the second layer.

In other words, when the second layer is formed by the coating method over the entire light emitting surface of the light emitting device, the amount of ink discharged to form the second layer is adjusted so that the optical film thickness of the second layer is sputtered. The second layer can be formed to have an optical film thickness distribution that cancels out the optical film thickness variation of the first layer formed by the method.

Thereby, it is possible to manufacture a light emitting device in which luminance unevenness and chromaticity deviation are suppressed.

It is sectional drawing which shows typically the structure of the organic EL element which concerns on embodiment of this invention. It is a fragmentary sectional view showing typically a part of manufacturing process of an organic display panel concerning an embodiment of the present invention. (A) is a fragmentary sectional view which shows the state in which the TFT layer was formed on the base material. (B) is a partial cross-sectional view showing a state in which an interlayer insulating layer is formed on the TFT layer. (C) is a partial sectional view showing a state in which an anode is formed on an interlayer insulating layer. (D) is a partial sectional view showing a state in which a hole injection layer is formed on the anode. FIG. 3 is a partial cross-sectional view schematically showing part of the process of manufacturing the organic EL display panel continued from FIG. 2. (A) is a fragmentary sectional view which shows the state by which the partition material layer was formed on the positive hole injection layer and the interlayer insulation layer. (B) is a fragmentary sectional view showing a state in which a partition layer is formed on the hole injection layer and the interlayer insulating layer. (C) is a partial cross-sectional view showing a state in which a hole transport layer is formed in the opening of the partition wall layer. (D) is a fragmentary sectional view showing a state in which a light emitting layer is formed on the hole transport layer in the opening of the partition wall layer. FIG. 4 is a partial cross-sectional view schematically showing a part of the manufacturing process of the organic EL display panel continued from FIG. 3. (A) is a fragmentary sectional view which shows the state in which the electron carrying layer was formed on the partition layer and the light emitting layer. (B) is a fragmentary sectional view showing a state where an electron injection layer is formed on the electron transport layer. (C) is a partial cross-sectional view showing a state in which a cathode and a sealing layer are formed on an electron injection layer. It is a schematic process drawing which shows the manufacturing process of the organic display panel which concerns on embodiment of this invention. It is a figure which shows the film thickness distribution of the positive hole injection layer in the organic display panel which concerns on embodiment of this invention. (A) is the figure which plotted the film thickness ratio of the representative point according to the area | region of the positive hole injection layer in the organic display panel which concerns on embodiment of this invention on the graph. (B) is the figure which plotted the chromaticity y value of B color in the representative point of (a) on the graph according to area | region. (C) is a figure which shows typically the area | region division in (a), (b). It is a figure which shows typically the film thickness distribution of the positive hole transport layer in the organic display panel which concerns on embodiment of this invention. It is a figure which shows typically the film thickness of the hole injection layer and hole transport layer in each of the 1st light emitting element of the organic display panel which concerns on embodiment of this invention, and a 2nd light emitting element. 1 is a schematic block diagram illustrating a schematic configuration of an organic EL display device according to an embodiment of the present invention.

<< Outline of One Embodiment of the Present Invention >>
In the method for manufacturing a light-emitting device according to one embodiment of the present invention, a first light-emitting element and a second light-emitting element having the same emission color are arranged on a substrate, and both the first light-emitting element and the second light-emitting element are A plurality of first and second electrodes, one having light reflectivity and the other having light transmissivity, and disposed between the first electrode and the second electrode, and including a first layer and a second layer A method of manufacturing a light emitting device having a stacked structure of functional layers, wherein the first layer of the first light emitting element and the first layer of the second light emitting element are formed by sputtering, The second layer of one light emitting element and the second layer of the second light emitting element are formed by a coating method, and optical in a direction orthogonal to the main surface of the substrate of the first layer and the second layer Regarding the film thickness, the optical film thickness of the first layer in the first light emitting element is Ds1, The optical film thickness of the first layer in the second light emitting element is Ds2, the optical film thickness of the second layer in the first light emitting element is Dw1, and the optical film thickness of the second layer in the second light emitting element is When Dw2, Ds1 <Ds2 and Dw1> Dw2 are satisfied.

According to the method for manufacturing a light emitting device according to one embodiment of the present invention, the optical thickness Ds2 of the first layer in the second light emitting element is thicker than the optical thickness Ds1 of the first layer in the first light emitting element. On the other hand, the optical film thickness Dw2 of the second layer in the second light emitting element is thinner than the optical film thickness Dw1 of the second layer in the first light emitting element. That is, in the first light emitting element, the relatively thin optical film thickness Ds1 of the first layer can be offset by the relatively thick optical film thickness Dw1 of the second layer. Similarly, in the second light emitting element, the relatively thick optical film thickness Ds2 of the first layer can be offset by the relatively thin optical film thickness Dw2 of the second layer.

In other words, when the second layer is formed by the coating method over the entire light emitting surface of the light emitting device, the amount of ink discharged to form the second layer is adjusted so that the optical film thickness of the second layer is sputtered. The second layer can be formed to have an optical film thickness distribution that cancels out the optical film thickness variation of the first layer formed by the method.

Thereby, the deviation between the optical distance in the first light emitting element and the optical distance in the second light emitting element is suppressed, the dispersion of the resonance effect of the light in the light emitting surface is suppressed, and the luminance unevenness and chromaticity deviation are suppressed. The manufactured light emitting device can be manufactured.

Here, “optical film thickness” means an optical distance in the thickness direction of the functional layer. Specifically, the physical film thickness of the functional layer is multiplied by the optical refractive index of the functional layer. Value.

In the specific aspect of the method for manufacturing a light-emitting device according to one embodiment of the present invention, the Ds1, the Ds2, the Dw1, and the Dw2 are the emission colors of the first light-emitting element and the second light-emitting element. The optical film thicknesses for forming the resonator structure are respectively set based on the wavelengths.

Thereby, it is possible to appropriately adjust the resonance effect in each light emitting element, and it is possible to improve light emission efficiency, suppress luminance unevenness, and suppress chromaticity deviation.

In a specific aspect of the method for manufacturing a light-emitting device according to one embodiment of the present invention, the first electrode is formed above the substrate using a light-reflective material, and the first electrode is formed above the first electrode. Forming one of the first layer and the second layer, forming the other of the first layer and the second layer above the one, forming a light emitting layer above the other, The second electrode is formed using a light-transmitting material above the light emitting layer, and the Ds1, Ds2, Dw1, and Dw2 satisfy a relationship of Ds1 + Dw1 = Ds2 + Dw2.

The above manufacturing method is a method of manufacturing a so-called top emission type light emitting device in which the first electrode is formed on the substrate side and has light reflectivity, and the second electrode is formed on the side opposite to the substrate and has light transmittance. It is. Moreover, in the said manufacturing method, a 1st layer and a 2nd layer are formed between the 1st electrode and light emitting layer which have light reflectivity. Therefore, the light emitted from the light emitting layer to the second electrode side passes through the second electrode and is directly extracted outside without passing through the first layer and the second layer (hereinafter referred to as “direct emission light”). "). On the other hand, the light emitted from the light emitting layer to the first electrode side passes through the first layer and the second layer, is reflected on the surface of the first electrode, and then passes again through the first layer and the second layer to the outside. (Hereinafter referred to as “reflected outgoing light”). Therefore, the resonance effect can be adjusted most efficiently by adjusting the optical film thicknesses of the first layer and the second layer.

At that time, a deviation between the optical distance in the first light emitting element and the optical distance in the second light emitting element is suppressed, and variation in the resonance effect of light in the light emitting surface is suppressed, resulting in uneven brightness and chromaticity deviation. It is possible to manufacture a light emitting device in which the above is suppressed.

In a specific aspect of the method for manufacturing a light-emitting device according to one embodiment of the present invention, the first electrode is formed above the substrate using a light-transmitting material, and above the first electrode. Forming a light emitting layer, forming one of the first layer and the second layer above the light emitting layer, forming the other of the first layer and the second layer above the one, The second electrode is formed on the other side using a material having light reflectivity, and the Ds1, the Ds2, the Dw1, and the Dw2 satisfy a relationship of Ds1 + Dw1 = Ds2 + Dw2.

The above manufacturing method is a method of manufacturing a so-called bottom emission type light emitting device in which the first electrode is formed on the substrate side and has light transmittance, and the second electrode is formed on the opposite side of the substrate and has light reflectivity. It is. Moreover, in the said manufacturing method, a 1st layer and a 2nd layer are formed between the 2nd electrode and light emitting layer which have light reflectivity. Therefore, as in the case of the top emission type, the resonance effect can be adjusted most efficiently by adjusting the optical film thicknesses of the first layer and the second layer.

At that time, a deviation between the optical distance in the first light emitting element and the optical distance in the second light emitting element is suppressed, and variation in the resonance effect of light in the light emitting surface is suppressed, resulting in uneven brightness and chromaticity deviation. It is possible to manufacture a light emitting device in which the above is suppressed.

In a specific aspect of the method for manufacturing a light-emitting device according to one embodiment of the present invention, the first layer is formed of a metal oxide, and the second layer is formed of an organic material above the first layer. It is characterized by.

Thereby, the first layer can be formed as a hole transport layer made of a metal oxide. In that case, for example, a hole injection layer can be formed as a tungsten oxide layer by a reactive sputtering method in an oxygen atmosphere using tungsten as a target member, and the manufacture is easy.

Further, the second layer can be formed as a hole transport layer made of an organic material having a hole transport property. In that case, a hole transport layer can be formed by a coating method using an organic material having a hole transport property, and the production is easy.

A light-emitting device according to another aspect of the present invention is a light-emitting device that includes a substrate and a first light-emitting element and a second light-emitting element that are disposed on the substrate and have the same emission color, and the first light-emitting element. Each of the second light-emitting elements is formed between the first electrode and the second electrode, at least one of which has a light transmitting property, and the first electrode and the second electrode, and is formed by a sputtering method. An optical film thickness in a direction perpendicular to the main surface of the substrate of the first layer and the second layer, and a laminated structure of a plurality of functional layers including one layer and a second layer formed by a coating method The optical film thickness of the first layer in the first light emitting element is Ds1, the optical film thickness of the first layer in the second light emitting element is Ds2, and the optical film of the second layer in the first light emitting element. The thickness is Dw1 and the second shot If the optical thickness of the second layer in the element and Dw2, Ds1 <Ds2, and, Dw1> characterized by satisfying the relation of Dw2.

According to the light emitting device according to another aspect of the present invention, in the first light emitting element, the optical film thickness Ds1 of the first layer is relatively thin, but the optical film thickness Dw1 of the second layer is relatively thick, It has been offset. Similarly, in the second light emitting element, the relatively thick optical thickness Ds2 of the first layer is offset by the relatively thin optical thickness Dw2 of the second layer. That is, the second layer is formed on the entire light emitting surface of the light emitting device with an optical film thickness distribution that cancels out the optical film thickness variation of the first layer.

Thereby, the deviation between the optical distance in the first light emitting element and the optical distance in the second light emitting element is suppressed, the dispersion of the resonance effect of the light in the light emitting surface is suppressed, and the luminance unevenness and chromaticity deviation are suppressed. It is possible to realize a light emitting device.

In a specific aspect of the light-emitting device according to another aspect of the present invention, the Ds1, the Ds2, the Dw1, and the Dw2 are the emission colors of the first light-emitting element and the second light-emitting element. The optical film thicknesses for forming the resonator structure are respectively set based on the wavelength.

Thereby, the resonance effect is appropriately adjusted in each light emitting element, and it is possible to improve the light emission efficiency, suppress the luminance unevenness, and suppress the chromaticity deviation.

In a specific aspect of the light emitting device according to another aspect of the present invention, the light emitting device further includes a light emitting layer between the first electrode and the second electrode, and the first electrode has light reflectivity. The first layer and the second layer are disposed between the first electrode and the light emitting layer, and Ds1, Ds2, Dw1, and Dw2 satisfy a relationship of Ds1 + Dw1 = Ds2 + Dw2. Features.

Since the first layer and the second layer are disposed between the light-reflecting first electrode and the light emitting layer, it is most efficient by adjusting the optical film thickness of the first layer and the second layer. The resonance effect can be adjusted. Thereby, the deviation between the optical distance in the first light emitting element and the optical distance in the second light emitting element is suppressed, the dispersion of the resonance effect of light in the light emitting surface is suppressed, and the luminance unevenness and chromaticity deviation are suppressed. It is possible to realize a light emitting device.

Further, in a specific aspect of the light emitting device according to another aspect of the present invention, the first layer is made of a metal oxide, the second layer is made of an organic material, and the first layer is made of the first layer. It is characterized by being arranged closer to the first electrode than the two layers.

Thereby, the first layer can be formed as a hole injection layer made of, for example, tungsten oxide. In this case, the hole injection layer can be formed as a tungsten oxide layer by a reactive sputtering method in an oxygen atmosphere using tungsten as a target member, and manufacturing is easy.

Further, the second layer can be formed as a hole transport layer made of an organic material. In this case, an organic material having a hole transporting property can be applied by, for example, an ink jet method to form a hole transporting layer, and the production is easy.

Hereinafter, specific examples of the embodiment and modification of the present invention will be shown, and the configuration, operation, and effect will be described.

Note that the embodiment and the modification used in the following description are examples used for easy understanding of the configuration, operation, and effect according to one aspect of the present invention, and the present invention is not limited to the essential part. The present invention is not limited to the following embodiments and modifications.

<Embodiment>
[1. Schematic configuration of organic EL display panel]
A schematic configuration of an organic EL display panel 100 according to an embodiment as an example of a light-emitting device that is one embodiment of the present invention will be described with reference to FIG.

FIG. 1 is a partially enlarged cross-sectional view of an organic EL display panel 100 according to an embodiment. The organic EL display panel 100 includes a plurality of light emitting elements 1 arranged in a matrix on a substrate 11. One light-emitting element corresponds to one sub-pixel (sub-pixel), and corresponds to one of the emission colors R (red), G (green), and B (blue). One pixel (pixel) is constituted by three sub-pixels (sub-pixels) corresponding to R, G, and B, respectively. That is, one pixel is composed of three light emitting elements 1 of a light emitting element 1R corresponding to R color, a light emitting element 1G corresponding to G color, and a light emitting element 1B corresponding to B color. The organic EL display panel 100 is a so-called top emission type color display panel whose upper side is the display surface.

In addition, when it is necessary to particularly distinguish the constituent elements according to the light emission colors, any of R, G, and B is added after the reference numerals of the constituent elements to indicate the corresponding light emission colors. If there is no need to distinguish between them, R, G, and B are not attached. For example, when the emission colors are not particularly distinguished, they are simply referred to as the light emitting element 1.

The organic EL display panel 100 includes a substrate 11, an interlayer insulating layer 12, an anode 13, a hole injection layer 14, a partition wall layer 15, a hole transport layer 16, a light emitting layer 17 (17R, 17G, 17B), an electron transport layer 18, An electron injection layer 19, a cathode 20, and a sealing layer 21 are provided. The substrate 11, the interlayer insulating layer 12, the electron transport layer 18, the electron injection layer 19, the cathode 20, and the sealing layer 21 are provided in common for a plurality of pixels. In the present embodiment, the hole injection layer 14, the hole transport layer 16, the light emitting layer 17, the electron transport layer 18, and the electron injection layer 19 are functional layers. The organic EL display panel 100 has a laminated structure in which these functional layers are laminated. Note that all the above layers may not necessarily be included in the functional layer, but the functional layer includes at least the light emitting layer 17. The functional layer includes a layer (first layer) formed by a sputtering method and a layer (second layer) formed by a coating method. For example, when the light emitting layer 17 is formed by a coating method, the light emitting layer 17 may be the second layer, or a layer formed by a coating method other than the light emitting layer 17 is included as the second layer. It may be.

Subsequently, the configuration of each part of the organic EL display panel 100 will be described.

<Board>
The substrate 11 includes a base material 111 that is an insulating material and a TFT (Thin Film Transistor) layer 112. In the TFT layer 112, a drive circuit (not shown) is formed for each subpixel. As a material for forming the base material 111, for example, glass is used. Specific examples of the glass material include alkali-free glass, soda glass, non-fluorescent glass, phosphate glass, borate glass, quartz glass, and the like.

<Interlayer insulation layer>
The interlayer insulating layer 12 is formed on the substrate 11. The interlayer insulating layer 12 is made of a resin material, and is for flattening a step on the upper surface of the TFT layer 112. As the resin material on which the interlayer insulating layer 12 is formed, for example, a positive photosensitive material is used. Examples of such photosensitive materials include acrylic resins, polyimide resins, siloxane resins, and phenol resins.

<Anode>
The anode 13 is made of a conductive material and is formed on the interlayer insulating layer 12 for each subpixel. Since the organic EL display panel 100 according to the present embodiment is a top emission type, the anode 13 may be formed of a conductive material having light reflectivity. Examples of the conductive material having light reflectivity include metals. Specifically, Ag (silver), Al (aluminum), aluminum alloy, Mo (molybdenum), APC (silver, palladium, copper alloy), ARA (silver, rubidium, gold alloy), MoCr (molybdenum and chromium) Alloy), MoW (alloy of molybdenum and tungsten), NiCr (alloy of nickel and chromium), and the like can be used. Further, the anode 13 may have a laminated structure of the conductive material having the light reflectivity and the transparent conductive material. In this case, as the transparent conductive material, ITO (Indium Tin Oxide), IZO (Indium Zinc Oxide), ZnO (zinc oxide), or the like can be used.

Although not shown in this cross-sectional view, a contact hole is formed in the interlayer insulating layer 12 for each sub-pixel. A TFT connection wiring is embedded in the contact hole, and the anode 13 is electrically connected to a drive circuit formed in the TFT layer 112 via the TFT connection wiring.

<Hole injection layer>
The hole injection layer 14 has a function of promoting injection of holes from the anode 13 to the light emitting layer 17. The hole injection layer 14 is made of, for example, a metal oxide and is disposed on the anode 13. The hole injection layer 14 is formed by, for example, a sputtering method. Examples of the metal oxide that is a material for forming the hole injection layer 14 include tungsten oxide (WOx), molybdenum oxide (MoOx), silver (Ag), chromium (Cr), vanadium (V), and nickel (Ni). An oxide such as iridium (Ir) can be used.

In the present embodiment, the hole injection layer 14 is made of tungsten oxide, and the hole injection layer 14 is formed by forming a tungsten oxide layer by reacting tungsten and oxygen using a reactive sputtering method. Is done.

<Partition wall layer>
The partition layer 15 is formed on the hole injection layer 14 in a state in which a part of the upper surface of the hole injection layer 14 is exposed and the peripheral region is covered. A region of the upper surface of the hole injection layer 14 that is not covered with the partition wall layer 15 (hereinafter referred to as “opening”) corresponds to a subpixel. That is, the partition wall layer 15 has an opening 15a provided for each subpixel.

The partition layer 15 is made of, for example, an insulating organic material (for example, acrylic resin, polyimide resin, novolac resin, phenol resin, or the like). The partition wall layer 15 functions as a structure for preventing the applied ink from overflowing when the light emitting layer 17 is formed by a coating method, and when the light emitting layer 17 is formed by a vapor deposition method, It functions as a structure for mounting a vapor deposition mask. In this embodiment, the partition layer 15 is made of a resin material, and for example, a positive photosensitive material can be used. Specific examples of such photosensitive materials include acrylic resins, polyimide resins, siloxane resins, and phenol resins. In this embodiment, a phenolic resin is used.

<Hole transport layer>
The hole transport layer 16 has a function of transporting holes injected from the hole injection layer 14 to the light emitting layer 17. The hole transport layer 16 is formed by applying an organic material solution and drying. As an organic material for forming the hole transport layer 16, polymer compounds such as polyfluorene and derivatives thereof, or polyarylamine and derivatives thereof can be used.

The hole transport layer 16 is composed of triazole derivative, oxadiazole derivative, imidazole derivative, polyarylalkane derivative, pyrazoline derivative and pyrazolone derivative, phenylenediamine derivative, arylamine derivative, amino-substituted chalcone derivative, oxazole derivative, styrylanthracene derivative, It may be formed using fluorenone derivatives, hydrazone derivatives, stilbene derivatives, porphyrin compounds, aromatic tertiary amine compounds and styrylamine compounds, butadiene compounds, polystyrene derivatives, hydrazone derivatives, triphenylmethane derivatives, tetraphenylbenzine derivatives. . Particularly preferably, a porphyrin compound, an aromatic tertiary amine compound and a styrylamine compound may be used. In this case, the hole transport layer 16 is formed by a vacuum evaporation method.

In the organic EL display panel 100 according to this embodiment, the hole transport layer 16 is formed by applying and drying an organic material solution.

<Light emitting layer>
The light emitting layer 17 includes an organic light emitting material and is formed in an opening 15 a located above the anode 13. The light emitting layer 17 has a function of emitting light of each color of R, G, and B by recombination of holes and electrons. In the organic EL display panel 100 according to the present embodiment, the light emitting layer 17 is formed by applying an ink containing an organic light emitting material into the opening 15a by inkjet.

Examples of the organic light emitting material included in the light emitting layer 17 include an oxinoid compound, a perylene compound, a coumarin compound, an azacoumarin compound, an oxazole compound, an oxadiazole compound, a perinone compound, a pyrrolopyrrole compound, a naphthalene compound, an anthracene compound, a fluorene compound, Fluoranthene compound, tetracene compound, pyrene compound, coronene compound, quinolone compound and azaquinolone compound, pyrazoline derivative and pyrazolone derivative, rhodamine compound, chrysene compound, phenanthrene compound, cyclopentadiene compound, stilbene compound, diphenylquinone compound, styryl compound, butadiene compound, Dicyanomethylenepyran compound, dicyanomethylenethiopyran compound, fluorescein compound, pyrylium Compound, thiapyrylium compound, serenapyrylium compound, telluropyrylium compound, aromatic aldadiene compound, oligophenylene compound, thioxanthene compound, cyanine compound, acridine compound, metal chain of 8-hydroxyquinoline compound, metal chain of 2-bipyridine compound And fluorescent materials such as a chain, a chain of a Schiff salt and a group III metal, an oxine metal chain, and a rare earth chain. Further, a known phosphor such as a metal complex that emits phosphorescence such as tris (2-phenylpyridine) iridium can be used. The light emitting layer 17 is formed using polyfluorene or a derivative thereof, polyphenylene or a derivative thereof, a polymer compound such as polyarylamine or a derivative thereof, or a mixture of the low molecular compound and the polymer compound. Also good.

<Electron transport layer>
The electron transport layer 18 is provided on the light emitting layer 17 and the partition wall layer 15 in common to a plurality of pixels, and has a function of transporting electrons injected from the cathode 20 to the light emitting layer 17. The electron transport layer 18 is formed using, for example, an oxadiazole derivative (OXD), a triazole derivative (TAZ), a phenanthroline derivative (BCP, Bphen), or the like.

<Electron injection layer>
The electron injection layer 19 is provided in common to a plurality of pixels on the electron transport layer 18 and has a function of promoting injection of electrons from the cathode 20 to the light emitting layer 17. The electron injection layer 19 includes, for example, a low work function metal such as lithium, barium, calcium, potassium, cesium, sodium, and rubidium, a low work function metal salt such as lithium fluoride, and a low work function metal oxide such as barium oxide. It is formed using etc.

<Cathode>
The cathode 20 is provided on the electron injection layer 19 in common for a plurality of pixels. The cathode 20 is made of, for example, a light transmissive material having conductivity such as ITO (indium tin oxide) or IZO (indium zinc oxide). By forming the cathode 20 using a transparent conductive material, light generated in the light emitting layer 17 can be extracted from the cathode 20 side. In addition to the above, for example, MgAg (magnesium silver) can be used as the transparent conductive material used for the cathode 20. In this case, the light can be transmitted by setting the thickness of the cathode 20 to about several tens of nm.

<Sealing layer>
A sealing layer 21 is provided on the cathode 20. The sealing layer 21 prevents impurities (water, oxygen) from entering the cathode 20, the electron injection layer 19, the electron transport layer 18, the light emitting layer 17 and the like from the opposite side of the substrate 11. Has a function to suppress deterioration. Since the organic EL display panel 100 according to the present embodiment is a top emission type display panel, the material of the sealing layer 21 is a light transmissive material such as SiN (silicon nitride) or SiON (silicon oxynitride). Used.

<Others>
Although not shown in FIG. 1, a color filter or an upper substrate may be placed on the sealing layer 21 and bonded. By placing and bonding the upper substrate, it is possible to further protect the cathode 20, the electron injection layer 19, the electron transport layer 18, the light emitting layer 17 and the like from impurities.

[2. Manufacturing method of organic EL display panel]
Next, an example of a method for manufacturing the organic EL display panel 100 will be described with reference to FIGS. 2 to 4 are partial sectional views schematically showing the manufacturing process of the organic EL display panel 100, and FIG. 5 is a schematic process diagram showing the manufacturing process of the organic EL display panel 100.

First, as shown in FIG. 2A, a TFT layer 112 is formed on a base material 111 to form a substrate 11 (step S1 in FIG. 5).

Next, as shown in FIG. 2B, an interlayer insulating layer 12 is formed on the substrate 11 (step S2 in FIG. 5). In this embodiment, an acrylic resin that is a positive photosensitive material is used as the interlayer insulating layer resin that is a material of the interlayer insulating layer 12. The interlayer insulating layer 12 is formed by applying an interlayer insulating layer solution in which an acrylic resin, which is an interlayer insulating layer resin, is dissolved in an interlayer insulating layer solvent (for example, PGMEA) on the substrate 11, and then baking. This is performed (step S3 in FIG. 5). Firing is performed at a temperature of 150 ° C. or higher and 210 ° C. or lower for 180 minutes, for example.

Subsequently, as shown in FIG. 2C, an anode 13 is formed on the interlayer insulating layer 12. The anode 13 is formed to a thickness of about 150 [nm] by vacuum deposition or sputtering (step S4 in FIG. 5). The anode 13 is formed for each subpixel.

Next, as shown in FIG. 2D, the hole injection layer 14 is formed on the anode 13 (step S5 in FIG. 5). In the organic EL display panel 100 according to the present embodiment, the hole injection layer 14 is a tungsten oxide layer and is formed by a reactive sputtering method.

Subsequently, as shown in FIG. 3A, a partition wall layer resin, which is a material of the partition wall layer 15, is applied on the hole injection layer 14 and the interlayer insulating layer 12 to form a partition wall material layer 150. For the partition layer resin, for example, a phenol resin, which is a positive photosensitive material, is used. For the partition wall material layer 150, a solution obtained by dissolving a phenol resin, which is a partition wall resin, in a solvent (for example, a mixed solvent of ethyl lactate and GBL) is applied to the hole injection layer 14 and the interlayer insulating layer 12 by a spin coating method or the like. It forms by apply | coating uniformly using. Then, the partition wall layer 15 is formed by performing pattern exposure and development on the partition wall material layer 150 (FIG. 3B, step S6 in FIG. 5), and the partition layer 15 is baked (step S7 in FIG. 5). As a result, an opening 15 a that is a formation region of the light emitting layer 17 is defined. The partition layer 15 is baked, for example, at a temperature of 150 ° C. or higher and 210 ° C. or lower for 60 minutes.

Further, in the step of forming the partition wall layer 15, the surface of the partition wall layer 15 may be further surface-treated with a predetermined alkaline solution, water, organic solvent, or the like, or may be subjected to plasma treatment. This is performed for the purpose of adjusting the contact angle of the partition wall layer 15 with respect to the ink (solution) applied to the opening 15a, or for the purpose of imparting water repellency to the surface.

Next, the ink containing the constituent material of the hole transport layer 16 is ejected from the nozzle 3030 of the inkjet head 301 to the opening 15a defined by the partition wall layer 15 and onto the hole injection layer 14 in the opening 15a. The hole transport layer 16 is formed by applying and baking (drying) (FIG. 3C, step S8 in FIG. 5).

Then, the ink containing the constituent material of the light emitting layer 17 is ejected from the nozzle 3030 of the ink jet head 301, applied onto the hole transport layer 16 in the opening 15 a, and baked (dried) to form the light emitting layer 17. (Step S9 in FIG. 3D and FIG. 5).

Subsequently, as shown in FIG. 4A, a material constituting the electron transport layer 18 is formed on the light emitting layer 17 and the partition wall layer 15 in common for each sub-pixel by vacuum deposition or sputtering. Then, the electron transport layer 18 is formed (step S10 in FIG. 5).

Next, as shown in FIG. 4B, the material constituting the electron injection layer 19 is formed on the electron transport layer 18 by a method such as a vapor deposition method, a spin coat method, or a cast method, and is applied to each subpixel. In common, the electron injection layer 19 is formed (step S11 in FIG. 5).

Then, as shown in FIG. 4C, a cathode 20 and a sealing layer 21 are formed on the electron injection layer 19. Specifically, first, the cathode 20 is formed by using a material such as ITO or IZO by vacuum deposition or sputtering (step S12 in FIG. 5). Subsequently, the sealing layer 21 is formed on the cathode 20 using SiN as a material by sputtering, CVD (Chemical Vapor Deposition), or the like (step S13 in FIG. 5).

The organic EL display panel 100 is completed through the above steps.

A color filter or an upper substrate may be placed on the sealing layer 21 and bonded.

[3. Variation in film thickness of layers formed by sputtering]
FIG. 6 is a diagram showing a film thickness distribution of the hole injection layer 14 formed by the reactive sputtering method. The film thickness of the hole injection layer 14 was measured with an optical film thickness meter. When measuring the film thickness of the hole injection layer 14 with an optical film thickness measuring instrument, it is difficult to measure if the partition wall layer 15 is present. Therefore, the actual film thickness measurement is performed using a dummy substrate without a partition wall layer. After going through the patterning process. Further, in FIG. 6, the film thicknesses in the respective panel regions are indicated by the film thickness ratio [%] based on the value of the thinnest film thickness.

As shown in FIG. 6, the hole injection layer 14 has the thinnest central portion, and there are relatively thick portions in the upper left, lower left, upper right, and lower right. The thickness ratio of the hole injection layer 14 was 100 to 117 [%] at the thinnest portion and 183 to 200 [%] at the thickest portion.

In the organic EL display panel 100 according to the present embodiment, the hole injection layer 14 is a tungsten oxide layer. When a tungsten oxide layer (hole injection layer 14) is formed by reactive sputtering, in this embodiment, oxygen is supplied from the oxygen supply port into the chamber, and the tungsten material in the chamber and oxygen react with each other by plasma. Thus, a tungsten oxide layer is formed. At this time, a tungsten oxide layer is formed in the chamber depending on factors such as the position and orientation of the oxygen supply port, the position where the tungsten target is disposed in the chamber, the oxygen supply rate, and the plasma generation conditions. There are places that are easily formed and places that are difficult to form. As a result, the thickness of the formed hole injection layer 14 varies.

FIG. 7A shows, based on the result of the film thickness distribution of FIG. 6, the organic EL display panel 100 has nine panel regions (upper left, upper, upper right, left, center, as shown in FIG. 7C). Right, lower left, lower, lower right), representative points are selected for each panel area, and the film thickness of the hole injection layer 14 (tungsten oxide layer) at the representative points is measured by an optical film thickness measuring instrument. It is the figure which measured by (1) and plotted the measurement result on the graph according to the area | region in a panel. In FIG. 7A, the film thickness of each region in the panel is shown by the film thickness ratio [%] based on the value of the thinnest film thickness.

As shown in FIG. 7A, the central portion has the smallest film thickness, the left and right regions are relatively thin, and the upper left, upper right, and upper right regions are relatively thick.

FIG. 7B is a diagram in which the chromaticity y value of the B color at the representative point in each of the above-described panel areas is plotted on a graph for each panel area. Chromaticity measurements were made on three samples. The hole injection layer 14 was formed by reactive sputtering using the same manufacturing apparatus and the same film formation conditions for all three samples.

As shown in FIG. 7B, the three samples showed the same tendency of chromaticity deviation. That is, the wavelength of the emitted light is shortest and close to blue at the center, and at the upper left and lower right, the wavelength of the emitted light tends to shift to the longer wavelength side, and the green wavelength component tends to increase. Such a chromaticity shift is considered to be caused by a variation in the optical distance in the light emitting element due to a variation in the thickness of the functional layer, and a difference in the wavelength of light enhanced by the resonance effect depending on the region in the panel. . That is, in the portion where the thickness of the functional layer is relatively thick, the wavelength of light from which the resonance effect is obtained shifts to the longer wavelength side, and light having a wavelength closer to green is strengthened by the resonance effect.

The tendency of the chromaticity shift shown in FIG. 7B is roughly the same as the film thickness distribution of the hole injection layer 14 shown in FIG. 6 and the film thickness of the hole injection layer 14 for each region in the panel shown in FIG. Match. This also seems to indicate that the film thickness variation of the hole injection layer 14 causes a chromaticity shift.

From the above results, the variation in the film thickness of the functional layer (in this embodiment, the hole injection layer 14) formed by the sputtering method causes a variation in the resonance effect, resulting in a chromaticity shift. Was confirmed. Here, FIG. 7B shows the measurement result of the chromaticity for the B color. However, the occurrence of the chromaticity shift is not limited to the B color, and similarly occurs in the R color and the G color. Note that in the case of white light, such as an organic EL lighting device, luminance unevenness is observed instead of chromaticity deviation.

Also, as can be seen from FIG. 7 (b), the three samples show the same chromaticity variation tendency. This indicates that the three samples have the same film thickness distribution of the hole injection layer 14. According to the tests by the inventors, it is confirmed that the functional layer to be formed has the same film thickness distribution if the manufacturing apparatus is the same and the film forming conditions are the same.

[3. Adjustment of optical distance by layer formed by coating method]
As described above, due to variations in the thickness of the functional layer formed by sputtering, the optical distance varies, and the intensity of the resonance effect of light and the wavelength at which the resonance effect is obtained vary depending on the region in the panel, Chromaticity deviation and luminance unevenness occur.

Therefore, in the organic EL display panel 100 according to the present embodiment, the functional layer formed by the coating method so as to have an optical film thickness distribution that cancels the variation in the optical film thickness of the functional layer formed by the sputtering method. Form. In the present embodiment, the film thickness variation of the hole injection layer 14 (FIG. 2D, step S5 in FIG. 5) formed by the reactive sputtering method is used as the hole transport layer 16 ( The case where the adjustment is performed in step S8 in FIGS. 3C and 5 will be described below.

FIG. 8 is a diagram schematically showing an example of the film thickness distribution of the hole transport layer 16 in the organic EL display panel 100 according to the present embodiment. As shown in FIG. 8, the hole transport layer 16 is applied with three different film thicknesses. That is, the thickness of the hole transport layer 16 is increased with respect to the subpixel existing in the region where the thickness of the hole injection layer 14 shown in FIG. 6 is the thinnest (the region having a thickness ratio of 100 to 133 [%]). (In this embodiment, for example, the film thickness ratio is 167 to 200 [%]). Further, the film thickness of the hole transport layer 16 is set to a subpixel existing in a region where the film thickness of the hole injection layer 14 shown in FIG. It is formed thin (in this embodiment, for example, a film thickness ratio of 100 to 133 [%]). Then, the film thickness of the hole transport layer 16 with respect to the sub-pixel in which the hole injection layer 14 shown in FIG. 6 exists in a region having an intermediate film thickness (region having a film thickness ratio of 133 to 167 [%]). Are formed to have an intermediate film thickness (in this embodiment, for example, a film thickness ratio of 133 to 167 [%]).

FIG. 9 is a plan view schematically showing different areas a and b in the organic EL display panel 100 formed as described above. The region a is included in the region (thickness ratio 100 to 117 [%]) in which the thickness of the hole injection layer 14 shown in FIG. 6 is the smallest, and the region b has the thickness of the hole injection layer 14. It is included in the thickest region (film thickness ratio 183 to 200 [%]). Moreover, the cross section of the 1st light emitting element 1a which exists in the area | region a, and the cross section of the 2nd light emitting element 1b which exists in the area | region b are each typically shown in the circle of a broken line. Here, both the first light emitting element 1a and the second light emitting element 1b have the emission color B.

As shown in FIG. 9, the optical film thickness of the hole injection layer 14 in the first light emitting element 1a is Ds1, the optical film thickness of the hole transport layer 16 is Dw1, and the hole injection layer 14 in the second light emitting element 1b Assuming that the optical film thickness is Ds2 and the optical film thickness of the hole transport layer 16 is Dw2, Ds1 <Ds2 and Dw1> Dw2. Furthermore, in this embodiment, the relationship of Ds1 + Dw1 = Ds2 + Dw2 is satisfied. That is, the total values of the optical film thicknesses of the hole injection layer 14 and the hole transport layer 16 are the same in the light emitting elements 1a and 1b. In other words, the optical distance when the light emitted from the light emitting layer 17B to the anode 13 side is emitted from the cathode 20 side to the outside after being reflected by the surface of the anode 13 is the light emitting element 1a and the light emitting element 1b. Are equal.

Thereby, it can adjust so that the more uniform and effective resonance effect may be acquired over the whole panel surface of the organic electroluminescence display panel 100, and generation | occurrence | production of brightness irregularity and chromaticity deviation can be suppressed. .

In the present embodiment, “film thickness” and “optical film thickness” mean the film thickness and the optical film thickness in the direction orthogonal to the main surface 11a of the substrate 11, respectively. The same applies to each modified example below.

In FIG. 9, the emission color of both the first light emitting element 1a and the second light emitting element 1b is B, but the present invention is not limited to this, and the emission color may be any of R, G, and B. However, the light emission colors of the first light-emitting element 1a and the second light-emitting element 1b are preferably the same regardless of the emission color. This is because the optical distance at which the resonance effect is efficiently obtained differs depending on the emission color. The value of Ds1 + Dw1 (= Ds2 + Dw2) may be a value that becomes an optical distance at which the resonance effect is efficiently obtained for each emission color.

In addition, in the example of the film thickness distribution of the hole transport layer 16 shown in FIG. 8, it has a structure composed of three kinds of film thicknesses (100 to 130%, 130 to 170%, 170 to 200%). Not limited. By setting the film thickness level more finely than the three types, it is possible to more accurately cancel out the film thickness variations of the layers formed by the sputtering method, and to suppress uneven brightness and chromaticity deviation more accurately. .

[4. Overall configuration of organic EL display device]
FIG. 10 is a schematic block diagram illustrating a configuration of an organic EL display device 1000 including the organic EL display panel 100. As shown in FIG. 10, the organic EL display device 1000 includes an organic EL display panel 100 and a drive control unit 200 connected thereto. The drive controller 200 includes four drive circuits 210 to 240 and a control circuit 250.

In the actual organic EL display device 1000, the arrangement of the drive control unit 200 with respect to the organic EL display panel 100 is not limited to this.

[5. Summary of Embodiment]
The organic EL display panel 100, which is a light emitting device according to the present embodiment, can be summarized as follows.

A light emitting device having a substrate and a first light emitting element and a second light emitting element which are arranged on the substrate and have the same emission color. Both the first light-emitting element and the second light-emitting element are disposed between the first electrode and the second electrode, at least one of which has light transmissivity, and the first electrode and the second electrode, and a sputtering method. A laminated structure of a plurality of functional layers including a first layer formed by the above and a second layer formed by a coating method. And about the optical film thickness in the direction orthogonal to the main surface of the said board | substrate of the said 1st layer and the said 2nd layer, let the optical film thickness of the said 1st layer in a said 1st light emitting element be Ds1, and said 2nd light emitting element When the optical film thickness of the first layer is Ds2, the optical film thickness of the second layer in the first light emitting element is Dw1, and the optical film thickness of the second layer in the second light emitting element is Dw2. , Ds1 <Ds2 and Dw1> Dw2.

Moreover, the manufacturing method of the organic EL display panel 100 which is the light emitting device according to the present embodiment can be summarized as follows.

A first light-emitting element and a second light-emitting element having the same emission color are disposed on a substrate, and one of the first light-emitting element and the second light-emitting element is light-reflective and the other is light-transmissive. A method of manufacturing a light emitting device, comprising: a first electrode having a first electrode; a second electrode having a second electrode; and a stacked structure of a plurality of functional layers disposed between the first electrode and the second electrode. is there.

The first layer of the first light emitting element and the first layer of the second light emitting element are formed by sputtering, and the second layer of the first light emitting element and the second layer of the second light emitting element are formed. The second layer is formed by a coating method.

And about the optical film thickness in the direction orthogonal to the main surface of the said board | substrate of the said 1st layer and the said 2nd layer, let the optical film thickness of the said 1st layer in a said 1st light emitting element be Ds1, and said 2nd light emitting element When the optical film thickness of the first layer is Ds2, the optical film thickness of the second layer in the first light emitting element is Dw1, and the optical film thickness of the second layer in the second light emitting element is Dw2. , Ds1 <Ds2 and Dw1> Dw2.

In the present embodiment, the first layer is the hole injection layer 14, and the second layer is the hole transport layer 16.

In the organic EL display panel 100 according to the present embodiment, since the hole transport layer 16 is formed by the ink jet method, the amount of ink applied (dropped) for each sub-pixel can be adjusted accurately and easily. . Therefore, it is possible to easily and accurately form the hole transport layer 16 having a film thickness distribution that cancels out the film thickness variation of the hole injection layer 14 formed by sputtering.

Thereby, as a whole panel, the variation in the optical film thickness of the functional layer is suppressed and becomes more uniform, and chromaticity deviation and luminance unevenness can be suppressed. In addition, in the case of the ink jet method, since the ink dropping amount can be finely adjusted in units of sub-pixels, it is suitable for the optical film thickness variation suppressing method as described above.

When mass-producing the organic EL display panel 100 according to the present embodiment, once the film forming conditions for the layers formed by the manufacturing apparatus and the sputtering method are determined, the following may be performed. First, a sample is formed under the film forming conditions using the manufacturing apparatus, and a film thickness distribution of a layer formed by a sputtering method in the formed sample is measured. Subsequently, based on the obtained film thickness distribution data, the amount of ink dropped on each sub-pixel of the layer formed by the coating method is determined. In the subsequent production of the product, a layer formed by the sputtering method is formed with the determined manufacturing apparatus and film formation conditions, and the formed ink is formed by the coating method with the determined amount of ink dropped for each sub-pixel. A layer may be formed. If the manufacturing apparatus and the film formation conditions are the same, the layer formed by sputtering has the same film thickness distribution no matter how many times it is formed, so the mass production method as described above is practical.

≪Modification≫
As described above, the present invention has been described based on the embodiments. However, the present invention is not limited to the above-described embodiments, and the following modifications can be implemented.

(Modification 1)
In the above embodiment, the film thickness variation of the hole injection layer 14 which is a layer formed by the sputtering method is offset by the hole transport layer 16, but the present invention is not limited to this.

For example, the light emitting layer 17 may be formed by a coating method with a film thickness distribution that cancels out the film thickness variation of the hole injection layer 14. In this case, when the optical distance of the light emitted from the light emitting layer 17 is calculated, if the light base point is set to the intermediate point in the thickness direction of the light emitting layer, it is related to the phase difference between the directly emitted light and the reflected emitted light. It should be noted that the thickness of the light emitting layer is halved. In this case, the hole injection layer 14 is the first layer, and the light emitting layer 17 is the second layer.

Further, the electron transport layer 18 may be formed by a coating method, and in this case, the film thickness distribution of the electron transport layer 18 is such that the film thickness distribution cancels out the film thickness variation of the hole injection layer 14. You may form in. In this case, the electron transport layer 18 is not common to each sub-pixel, and may be formed separately for each sub-pixel. In this case, the hole injection layer 14 is the first layer, and the electron transport layer 18 is the second layer.

(Modification 2)
In the above-described embodiment, the layer formed by the sputtering method, which is the object of offsetting the film thickness variation, is the hole injection layer 14, but is not limited thereto.

For example, the light emitting layer may be formed by sputtering using an inorganic material, and the electron injection layer may be formed by sputtering. In that case, the light-emitting layer or the electron injection layer may be a target for offsetting the film thickness variation. That is, the film thickness variation of the light emitting layer and the electron injection layer formed by the sputtering method may be offset by the layer formed by the coating method (for example, the hole transport layer).

In this modification, the light emitting layer or the electron injection layer is the first layer, and the layer formed by the coating method (for example, the hole transport layer) is the second layer.

(Modification 3)
The hole injection layer 14 may be formed using a conductive polymer material such as PEDOT (a mixture of polythiophene and polystyrene sulfonic acid) or polyaniline. In this case, the hole injection layer 14 is formed by a coating method (wet process). When the hole injection layer 14 is formed by a coating method, a partition wall layer is required in the formation process. Therefore, after the partition layer 15 is formed and before the hole transport layer 16 is formed, the hole injection layer 14 is formed. Formation takes place. In this case, the hole transport layer is the second layer.

Also in the configuration of the modification example 3, as in the modification example 2, the film thickness variation of the light emitting layer and the electron injection layer formed by the sputtering method may be offset by the hole injection layer formed by the coating method. In that case, since the hole injection layer is formed first, if the hole injection layer is formed in a film thickness distribution that cancels in advance the film thickness variation of the light emitting layer and electron injection layer formed later Good.

(Modification 4)
The hole injection layer 14 may be formed by combining a layer formed by a dry process such as a sputtering method and a layer formed by a coating method (wet process). In that case, the film thickness variation of the layer formed by the dry process may be offset by the layer formed by the wet process. In this case, the layer formed by the dry process is the first layer, and the layer formed by the wet process is the second layer.

(Modification 5)
In the above embodiment, in order to illustrate the relationship between the thicknesses of the hole injection layer 14 and the hole transport layer 16 in FIG. Although the light-emitting element 1b exists in the region where the thickness of the hole injection layer 14 is thickest, it is not limited to this. The light emitting elements 1 a and 1 b may exist in any region within the panel surface of the organic EL display panel 100 as long as the hole injection layer 14 has a different film thickness.

Further, although the light emitting element 1a and the light emitting element 1b are assumed to have the same emission color, the present invention is not limited to this. When the adjustment of the optical distance for each emission color is performed in a layer other than the hole injection layer 14 and the hole transport layer 16 (for example, the emission layer 17), the emission colors of the light emitting element 1a and the light emitting element 1b are different. Alternatively, the variation in the optical film thickness of the hole injection layer 14 may be offset by the optical film thickness distribution of the hole transport layer 16. In this case, since it is not necessary to consider the film thicknesses of the hole injection layer 14 and the hole transport layer 16 when adjusting the optical distance for each emission color, the design is easy.

(Modification 6)
The organic EL display panel 100 according to the above embodiment is a top emission type, but is not limited thereto, and may be a bottom emission type. In that case, since the anode 13 has light transmittance and the cathode 20 has light reflectivity, the optical film thickness is adjusted between the two layers arranged on the cathode 20 side with respect to the light emitting layer 17. More effective.

(Modification 7)
When the optical film thickness is adjusted by two layers arranged between the light emitting layer and the electrode having light reflectivity, the optical distance can be adjusted most effectively. However, the adjustment of the optical film thickness is not limited to the two layers described above, and may be performed by any two of the plurality of functional layers sandwiched between the cathode and the anode. Even in this case, a luminance unevenness suppressing effect and a chromaticity shift suppressing effect can be obtained to some extent.

(Modification 8)
In the said embodiment, although the organic electroluminescent display panel 100 which is a color display panel was demonstrated to the example as a light-emitting device which concerns on 1 aspect of this invention, it is not restricted to this. The light emitting device according to one embodiment of the present invention may be an organic EL lighting device. In this case, since the plurality of light emitting elements 1 included in the organic EL lighting device are all white in emission color, it is not necessary to adjust the optical distance for each emission color, and the design is easy. In addition, the light emission colors of the first light emitting element 1a and the second light emitting element 1b are necessarily the same.

(Modification 9)
In the above embodiment, the case of the reactive sputtering method as the sputtering method has been described as an example. However, the present invention is not limited to this. For example, even in the magnetron sputtering method, the film thickness varies due to the magnetic fields of a plurality of magnetrons arranged. Therefore, the film thickness variation of the layer formed by the magnetron sputtering method may be offset by the layer formed by the coating method.

As described above, the organic light emitting device and the display device according to the present invention have been described based on the embodiments and the respective modifications. However, the present invention is not limited to the above embodiments and the respective modifications. A form obtained by making various modifications conceivable by those skilled in the art to the above-described embodiment and each modification, or by arbitrarily combining the components and functions in the embodiment and each modification without departing from the spirit of the present invention. Implemented forms are also included in the present invention.

The present invention is useful for manufacturing a light emitting device in which luminance unevenness or chromaticity deviation is suppressed.

DESCRIPTION OF SYMBOLS 1a 1st light emitting element 1b 2nd light emitting element 11 Board | substrate 13 Anode (1st electrode)
14 Hole injection layer (first layer)
16 Hole transport layer (second layer)
17 Light emitting layer 20 Cathode (second electrode)
100 Organic EL display panel (light emitting device)

Claims (9)

A first light-emitting element and a second light-emitting element having the same emission color are disposed on a substrate, and one of the first light-emitting element and the second light-emitting element is light-reflective and the other is light-transmissive. A method of manufacturing a light emitting device, comprising: a first electrode having a first electrode; a second electrode having a second electrode; and a stacked structure of a plurality of functional layers disposed between the first electrode and the second electrode. There,
Forming the first layer of the first light emitting element and the first layer of the second light emitting element by a sputtering method;
Forming the second layer of the first light emitting element and the second layer of the second light emitting element by a coating method;
Regarding the optical film thickness of the first layer and the second layer in the direction perpendicular to the main surface of the substrate, the optical film thickness of the first layer in the first light emitting element is Ds1, and the optical film thickness in the second light emitting element is When the optical film thickness of the first layer is Ds2, the optical film thickness of the second layer in the first light emitting element is Dw1, and the optical film thickness of the second layer in the second light emitting element is Dw2,
A method for manufacturing a light-emitting device that satisfies a relationship of Ds1 <Ds2 and Dw1> Dw2. The Ds1, the Ds2, the Dw1, and the Dw2 are respectively set to optical film thicknesses that form a resonator structure based on wavelengths of the emission colors of the first light emitting element and the second light emitting element. The method for manufacturing a light emitting device according to claim 1. Forming the first electrode on the substrate using a light-reflective material;
Forming one of the first layer and the second layer above the first electrode;
Forming the other of the first layer and the second layer above the one;
A light emitting layer is formed on the other side;
Forming the second electrode above the light emitting layer using a light transmissive material,
The Ds1, the Ds2, the Dw1, and the Dw2 are
The method for manufacturing a light emitting device according to claim 1, wherein the relationship of Ds1 + Dw1 = Ds2 + Dw2 is satisfied. Forming the first electrode using a light-transmitting material above the substrate;
Forming a light emitting layer above the first electrode;
Forming one of the first layer and the second layer above the light emitting layer;
Forming the other of the first layer and the second layer above the one;
Forming the second electrode on the other side using a material having light reflectivity,
The Ds1, the Ds2, the Dw1, and the Dw2 are
The method for manufacturing a light emitting device according to claim 1, wherein the relationship of Ds1 + Dw1 = Ds2 + Dw2 is satisfied. Forming the first layer from a metal oxide;
The method for manufacturing a light-emitting device according to claim 3, wherein the second layer is formed of an organic material above the first layer. A light-emitting device having a substrate and a first light-emitting element and a second light-emitting element that are arranged on the substrate and have the same emission color,
Both the first light-emitting element and the second light-emitting element are disposed between the first electrode and the second electrode, at least one of which has light transmissivity, and the first electrode and the second electrode, and a sputtering method. A multilayer structure of a plurality of functional layers including a first layer formed by the above and a second layer formed by a coating method,
Regarding the optical film thickness of the first layer and the second layer in the direction perpendicular to the main surface of the substrate, the optical film thickness of the first layer in the first light emitting element is Ds1, and the optical film thickness in the second light emitting element is When the optical film thickness of the first layer is Ds2, the optical film thickness of the second layer in the first light emitting element is Dw1, and the optical film thickness of the second layer in the second light emitting element is Dw2,
A light-emitting device that satisfies the relationship of Ds1 <Ds2 and Dw1> Dw2. The Ds1, the Ds2, the Dw1, and the Dw2 are respectively set to optical film thicknesses that form a resonator structure based on wavelengths of the emission colors of the first light emitting element and the second light emitting element. The light emitting device according to claim 6. A light emitting layer is further provided between the first electrode and the second electrode;
The first electrode has light reflectivity,
The first layer and the second layer are disposed between the first electrode and the light emitting layer,
The Ds1, the Ds2, the Dw1, and the Dw2 are
The light emitting device according to claim 6 or 7, wherein a relationship of Ds1 + Dw1 = Ds2 + Dw2 is satisfied. The first layer is made of a metal oxide,
The second layer is made of an organic material,
The light emitting device according to claim 8, wherein the first layer is disposed closer to the first electrode than the second layer.

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