JP2009043614A - Manufacturing method of organic EL display - Google Patents

Abstract

The present invention provides a method for simultaneously solving the problem of forming a color conversion layer with high definition and improving the external extraction efficiency of blue-green light of a blue-green light emitting element.
A transparent electrode provided in contact with an organic EL layer of an organic EL element unit to be bonded to a color filter substrate comprises two layers of a first transparent conductive layer and a second transparent conductive layer from the organic EL layer side. The refractive index of one transparent conductive layer is larger than the refractive index of the second transparent conductive layer, and the second transparent conductive layer has an opening in a region facing at least one type of filter portion of the color filter. In the method for manufacturing an organic EL display, a color conversion layer that is in close contact with the upper transparent electrode and converts light emitted from the light emitting layer into visible light having a longer wavelength is formed thinner than the depth of the opening. The color conversion layer on the second transparent conductive layer other than the opening is peeled off with a pressure-sensitive adhesive tape, and the total film thickness of the color conversion layer and the protective layer on the color conversion layer of the opening is larger than the depth of the opening. Shape the protective layer to be thicker The method of manufacturing an organic EL display, characterized by.
[Selection] Figure 2

Description

  The present invention relates to a method for manufacturing an organic EL display. The organic EL display obtained by the method of the present invention is a multicolor light emission used in personal computers, word processors, televisions, facsimiles, audios, videos, car navigation, electric desk calculators, telephones, portable terminals, industrial measuring instruments, and the like. It can be used for an organic EL display.

  In recent years, organic EL displays have been actively researched for practical use. Since an organic EL display can realize a high current density at a low voltage, it is expected to be put to practical use as a display having high light emission luminance and light emission efficiency and capable of high-definition multi-color or full-color display. As an example of a multi-color or full-color method for organic EL displays, a blue-green light emitting element and the light from this element are absorbed and converted into light containing longer wavelength visible light (green light to red light). A color conversion method is proposed in which a display is configured by patterning pixels that emit red (R), green (G), and blue (B), which are the three primary colors, using a color conversion film. . For example, as a method for forming a color conversion film, an organic EL display panel in which a color conversion material is deposited by a dry process such as vapor deposition or sputtering is disclosed (for example, see Patent Document 1).

  As a method of patterning a color conversion layer on which a color conversion material is deposited using a dry process such as vapor deposition or sputtering, a color mask is used for color conversion when depositing the color conversion material. A method of depositing material is common.

  In Patent Document 2, a fluorescent conversion film, which is a color conversion material, is embedded in a concave portion provided on the surface of a transparent substrate using a wet process, and the surface of the fluorescent conversion film is polished so that it is not inside the concave portion of the substrate surface. It is disclosed that the formed fluorescence conversion film is removed.

  Patent Document 3 discloses a removal method in which an organic film of an organic EL element is deposited on the entire surface, and then an organic film in a portion other than the light emitting pattern is peeled off with an adhesive tape. In order to increase the adhesive strength of the part of the adhesive tape to be peeled off, ultraviolet rays are exposed using an exposure mask.

JP 2002-075643 A JP-A-10-208879 JP 2003-086368 A

  However, the color conversion film in Patent Document 2 has a thickness of 10 μm or more formed by a wet process and can withstand the wet environment during polishing and cleaning. However, the color conversion film formed by vapor deposition has a thickness of 1 μm. Is not a technology that can be applied as it is because it is difficult to withstand polishing and its characteristics deteriorate in a wet environment.

  Further, the technique described in Patent Document 3 cannot be applied to a full color display of RGB pixels in which a color conversion layer is provided on the upper transparent electrode. This is because when a color conversion unit is formed in a portion corresponding to a specific red pixel, it is not necessary to form a color conversion unit for other green and blue pixels, and an organic layer for color conversion formed on the entire surface of the substrate is formed. This is because it is necessary to irradiate ultraviolet rays in order to peel off on these pixels, but when the pixel part is irradiated with ultraviolet rays, there is a problem that the characteristics of the light emitting layer material deteriorate. Moreover, it is not practical to form a shielding mask pattern corresponding to the fine pattern of the red pixel on the peeling substrate. Furthermore, in the above patent document, it is disclosed that a groove is provided in the base around the peeling portion. However, the depth of the groove is required to be sufficiently deeper than the film to be peeled off. Therefore, a separation method that does not affect the groundwork has been desired.

  In the top emission type organic EL display, blue light from the blue-green light emitting element is used in the blue pixel portion. However, in the organic EL element having a thin film multilayer structure, the interface, particularly outside (atmosphere), is used. Reflection at the transparent electrode interface from which light is emitted is large. For example, in the case of IZO, the reflectance is as high as 15%, and there is a problem that sufficient light is not extracted outside.

  That is, in a full-color organic EL display, there has been a demand for a method for simultaneously solving high-definition pattern formation of the color conversion layer and improving the blue-green light external extraction efficiency of the blue-green light emitting element.

  The present invention has been made in view of such a situation, and the gist thereof is that the transparent electrode provided in contact with the organic EL layer of the organic EL element unit to be bonded to the color filter substrate is the first transparent conductive layer from the organic EL layer side. The first transparent conductive layer has a refractive index greater than that of the second transparent conductive layer, and the second transparent conductive layer includes at least one color filter. An opening portion is provided in a region facing the filter portion, and a color conversion layer that is in close contact with the transparent electrode and converts light emitted from the light emitting layer into light containing visible light having a longer wavelength than the depth of the opening portion. Is formed, and then the color conversion layer on the second transparent conductive layer other than the opening is peeled off with a pressure-sensitive adhesive tape.

The protective layer may be formed after the color conversion layer at the opening is peeled off with the pressure-sensitive adhesive tape.
Or after forming a protective layer on a color conversion layer, you may peel color conversion layers and protective layers other than an opening part with a pressure-sensitive adhesive tape.
The total thickness of the color conversion layer and the protective layer is preferably thicker than the depth of the opening.
In addition, it is preferable to separate the openings and the portions other than the openings by irradiating the periphery of the openings with an energy beam after the formation of the protective layer and before peeling with the pressure-sensitive adhesive tape.
The energy beam is preferably a femtosecond laser.
Moreover, it is preferable that the area | region which provides an opening part opposes the red filter part of a color filter substrate.

  With the above configuration, light emitted from the blue-green light emitting element can be efficiently extracted to the outside, and a pattern of the color conversion film formed by the vapor deposition method can be accurately formed. Moreover, according to the said preferable aspect, since a color conversion material is peeled and removed after covering with a protective film, it is protected from an environment and can fully exhibit the characteristic.

Hereinafter, an embodiment of the present invention will be described with reference to FIG.
FIG. 1 is a schematic structural view of a top emission type organic EL display of the present invention. This display is configured by bonding an organic EL element portion 1 and a color filter substrate 2 together. The organic EL element portion has a structure in which a substrate 11, a lower reflective electrode 12, an organic EL layer 13, a first transparent conductive layer 14, and a second transparent conductive layer 15 are laminated, and the first transparent conductive layer 14 and the second transparent conductive layer. Layer 15 forms the upper transparent electrode. In the portion of the second transparent conductive layer 15 facing the red filter 22R of the filter substrate 21, the color conversion layer 17 is embedded with the protective layer 18 as a cap layer. The lower reflective electrodes are electrically insulated by an insulating film 19.

  The substrate 11 may be a polymer material such as glass, ceramic, silicon or polycarbonate, polyethylene terephthalate, polyethylene naphthalate. When a polymer material is used, the substrate 11 may be rigid or flexible. On the substrate 11, a plurality of switching elements (TFTs, etc.) and wirings for the elements are formed.

The lower reflective electrode 12 is an electrode that defines an independent light emitting portion of the top emission type organic EL display of the present embodiment, and is composed of a plurality of partial electrodes, each of which is connected to the switching element on a one-to-one basis. Is done. The lower reflective electrode 12 is made of a highly reflective metal (Al, Ag, Mo, W, Ni, Cr, etc.), an amorphous alloy (NiP, NiB, CrP, CrB, etc.), or a microcrystalline alloy (NiAl, etc.). It can be formed by a dry process such as vapor deposition. Optionally, an insulating metal oxide (TiO ₂ , ZrO ₂ , AlO _x, etc.) or an insulating metal nitride (AlN, SiN, etc.) is provided in the gap between the plurality of partial electrodes of the reflective electrode 12. Alternatively, the insulating film 19 may be formed.

  Next, the organic EL layer 13 is formed on the lower reflective electrode 12. The organic EL layer 13 includes at least an organic light emitting layer, and has a structure in which a hole injection layer, a hole transport layer, an electron transport layer and / or an electron injection layer are interposed as required. Specifically, the organic EL layer 13 has a layer structure as described below.

(1) Anode / organic light emitting layer / cathode (2) Anode / hole injection layer / organic light emitting layer / cathode (3) Anode / organic light emitting layer / electron injection layer / cathode (4) Anode / hole injection layer / organic Light emitting layer / electron injection layer / cathode (5) Anode / hole transport layer / organic light emitting layer / electron injection layer / cathode (6) Anode / hole injection layer / hole transport layer / organic light emitting layer / electron injection layer / Cathode (7) Anode / hole injection layer / hole transport layer / organic light emitting layer / electron transport layer / electron injection layer / cathode In the above layer structure, the anode and the cathode are either the lower reflective electrode 12 or the upper transparent electrode. It is.

  As a material of each layer constituting the organic EL layer 13, a known material is used. Moreover, each layer which comprises the organic EL layer 13 can be formed using arbitrary methods known in the said techniques, such as a vapor deposition method. For example, organic light-emitting layer materials for obtaining blue to blue-green light emission include fluorescent brighteners such as benzothiazole, benzimidazole, and benzoxazole, metal chelated oxonium compounds, and styrylbenzene. Materials such as compounds and aromatic dimethylidin compounds are preferably used.

An upper transparent electrode is formed on the organic EL layer 13. The upper transparent electrode is a common electrode formed integrally.
The upper transparent electrode is made of ITO, tin oxide, indium oxide, IZO, zinc oxide, zinc-aluminum oxide, zinc-gallium oxide, or conductive transparent in which dopants such as F and Sb are added to these oxides. It can be formed using a metal oxide. The transparent electrode is formed using a vapor deposition method, a sputtering method, or a chemical vapor deposition (CVD) method, and preferably formed using a sputtering method. When the refractive index of the upper transparent electrode is larger than the refractive index (1.8 to 1.9) of the organic film, the light extraction becomes larger.

In the present invention, the transparent electrode is composed of two layers, a first transparent conductive layer 14 and a second transparent conductive layer 15. The refractive index of the first transparent conductive layer 14 needs to be larger than the refractive index of the second transparent conductive layer 15. The first transparent conductive layer 14 does not mainly serve as a charge injection electrode. The refractive index of the second transparent conductive layer 15 is adjusted to reduce the reflectance at the external interface. The film thickness of the first transparent conductive layer 14 is preferably 50 nm to 300 nm and the refractive index is preferably 2.0 to 2.2. The film thickness of the second transparent conductive layer 15 formed thereon is 150 nm to 500 nm. The refractive index is preferably 1.8 to 2.0. Since the transparent conductive film has a high refractive index, the light extraction efficiency is improved, and the light output from the EL layer is improved.
An opening 16 is provided at a predetermined position of the second transparent conductive layer 15 (a region facing at least one filter portion of the color filter). In FIG. 1, the predetermined position is a region facing the red filter 22 </ b> R of the color filter substrate 2.

  A color conversion layer 17 is provided on the first transparent conductive layer 14 in the opening 16 of the second transparent conductive layer 15. The color conversion layer 17 is a layer formed from one or more types of color conversion dyes, and the film thickness of the color conversion layer is made smaller than the depth of the opening provided in the second transparent conductive film. By doing in this way, the color conversion layer 17 is formed to the intermediate depth in the said opening part, and the below-mentioned protective layer 18 is formed as a cap on it. The film thickness of the color conversion layer 17 is preferably 1 μm or less, more preferably 100 nm to 400 nm. Examples of the color conversion dye for forming the color conversion layer 17 include 3- (2-benzothiazolyl) -7-diethylaminocoumarin (coumarin 6), 3- (2-benzimidazolyl) -7-diethylaminocoumarin (coumarin 7), and coumarin. Coumarin dyes such as 135; naphthalimide dyes such as Solvent Yellow 43 and Solvent Yellow 44; 4-dicyanomethylene-2-methyl-6- (p-dimethylaminostyryl) -4H-pyran (DCM-1, ( I)), cyanine dyes such as DCM-2 (II) and DCJTB (III); xanthene dyes such as rhodamine B and rhodamine 6G; pyridine dyes such as pyridine 1; 4,4-difluoro-1,3, 5,7-tetraphenyl-4-bora-3a, 4a-diaza-s-indacene (IV), lumogen F red, Nile red (V), etc. can be used.

  A protective layer 18 is provided so as to cover the color conversion layer 17 provided in the opening 16 of the second transparent conductive layer 15. The total film thickness of the color conversion layer 17 and the protective layer 18 is thicker than the depth of the opening 16. The protective layer 18 is a layer for protecting the color conversion layer 17. Further, it is desirable that the protective layer 18 can be removed under conditions for patterning the color conversion layer 17 described later and can be formed under conditions that do not damage the color conversion layer 17. Suitable materials for forming the protective layer 18 include inorganic materials such as silicon oxide, silicon nitride, silicon oxynitride.

Next, the manufacturing method of the upper transparent electrode of the organic EL element part 1 is demonstrated with reference to FIG.
First, as shown in FIG. 2A, the first transparent conductive layer 14 and the second transparent conductive layer 15 are sequentially formed by sputtering or the like.

  The multilayer upper transparent electrode composed of the first transparent conductive layer 14 and the second transparent conductive layer 15 is formed by changing the refractive index without impairing various characteristics such as electric resistance and transmittance. In a film forming method such as an ion plating method, it is possible to change the film forming power and / or change the oxygen concentration in the film forming atmosphere. As a result of examination of transparent electrode film formation, it was found that when the film formation power is high, the specific resistance of the transparent conductive film increases and the refractive index of the film increases. By adopting such a method, it is possible to obtain a predetermined multilayer transparent electrode with one apparatus without changing the target in the same film forming chamber.

  Next, as shown in FIG. 2B, an opening 16 is provided at a predetermined position of the second transparent conductive layer 15 using a photolithography method. A method such as dry etching or wet etching can be used to remove the second transparent conductive layer. This predetermined position is a region facing at least one type of filter part of the color filter 22, and is a part facing the red filter in the example of FIG.

  Next, as shown in FIG. 2C, the color conversion layer 17 is formed on the entire surface of the second transparent conductive layer 15 by vapor deposition. At this time, the film thickness of the color conversion layer 17 is smaller than the depth of the opening 16, that is, the thickness of the second transparent conductive layer 15. Next, as shown in FIG. 2D, the protective layer 18 is formed on the entire surface of the color conversion layer 17. At this time, the thickness of the protective layer 18 is preferably such that the total film thickness with the color conversion layer 17 in the opening 16 is equal to or greater than the depth of the opening 16. For the formation of the protective layer 18, a dry process such as a CVD method, a vapor deposition method, or a sputtering method can be used.

  Next, as shown in FIG. 2E, the color conversion layer 17 and the protective layer 18 are peeled and removed using a pressure-sensitive adhesive tape so that the surface of the original second transparent conductive layer 15 is exposed. As a result, the color conversion part 17 is formed in the opening 16, and the second transparent conductive layer 15 is exposed in the other areas, and light from the blue-green light emitting element is emitted to the outside with reduced reflection loss. This completes the configuration. In this case, the second transparent conductive layer 15 serves as a protective layer except for the portion facing the red filter 22R. In addition, as shown in FIG. 3, the color conversion layer 17 may be peeled and removed first, and then the protective film 18 may be formed.

  That is, the color conversion layer 17 is formed on the entire surface of the second transparent conductive layer 15 in the same manner as in FIGS. 2A to 2C until FIG. Next, as shown in FIG. 3B, the color conversion layer 17 formed on the second transparent conductive layer 15 is peeled and removed, leaving only the color conversion layer 17 of the opening 16 and the desired color conversion layer. Pattern can be obtained. Next, as shown in FIG. 3C, a protective layer 18 may be formed.

  In addition, in order to confirm the validity of peeling using the pressure-sensitive adhesive tape described above, Sample 1 in which a transparent conductive film was formed on a glass substrate, Sample 2 in which a color conversion film was formed on the transparent conductive film, and transparent conductive film 3 samples of sample 3 in which a silicon nitride film was further formed as a protective film on the color conversion film were prepared, and a peel test according to JIS D0202 was performed on these samples. There was no peeling in the film. In sample 2, the entire color conversion film was peeled off. In sample 3, peeling from the color conversion film occurred 100%.

  As a method for removing the color conversion layer 17 or the laminate of the color conversion layer 17 and the protective layer 18 in the present invention, peeling with a pressure-sensitive adhesive tape is preferable. Using a commercially available pressure-sensitive adhesive pressure-sensitive adhesive tape, a tape coated with a silicone adhesive, a cellophane tape, or the like, the color conversion layer 17 or the laminate of the color conversion layer 17 and the protective layer 18 formed other than the openings 16 is removed. . The color conversion layer 17 may be peeled off before the protective layer is formed, and then the protective layer 18 may be formed on the color conversion layer 17. In this case, the color conversion layer 17 in the opening 16 is in a hole that is recessed from the other color conversion layer (the color conversion layer formed on the second transparent conductive layer 15), so that it contacts the tape or the like. It is held without.

  When the laminate of the color conversion layer 17 and the protective layer 18 is removed, as shown in FIG. 4A, when a part of the protective layer 18 is continuous with the protective layer on the opening 16, as shown in FIG. It is also preferable to make a cut in advance so as to surround the opening 16 (for example, a region facing the red filter row of the color filter substrate 2) with an energy beam as shown in FIG. Then, by peeling off the laminate or the protective layer on the second transparent conductive layer, only the laminate in the opening is left as shown in FIG. 4C, and the laminate is peeled off cleanly. . When a femtosecond laser is used as an energy beam, thermal damage to the processed surface can be reduced and separation can be performed with high accuracy.

  After peeling off the laminate of the color conversion layer 17 and the protective layer 18, using a rotary polishing machine as necessary, using ceramic fine particles such as alumina as an abrasive, polishing with water, and polishing the peeled surface Good.

Example 1
As the substrate 11, 1737 glass manufactured by Corning, which was washed with pure water and dried and was 50 × 50 × 0.7 mm was used. Next, the lower reflective electrode 12 was a laminate of CrB / IZO. That is, first, CrB having a thickness of 100 nm was formed on a glass substrate. A power of 300 W was applied using Ar as the sputtering gas. Further, 100 nm of IZO was laminated on the CrB film by sputtering with 250 W power using Ar as a sputtering gas, and photoetching was performed with a mixed acid (nitric acid 2%, phosphoric acid 70%, acetic acid 10%), a width of 0.204 mm, A stripe pattern with a gap of 0.134 mm was formed.

  Next, a positive photoresist [WIX-2A] (trade name, manufactured by ZEON CORPORATION) was used, and an insulating film having a thickness of 0.5 μm was formed on the entire surface of the substrate except that the pixel formation portion was an opening.

Next, the substrate on which the lower reflective electrode 12 was formed was mounted in a resistance heating vapor deposition apparatus, and an electron transport layer, an organic light emitting layer, and a hole transport layer were sequentially formed without breaking the vacuum. The vacuum chamber pressure during deposition was reduced to 1 × 10 ^-4 Pa. The electron transport layer was formed by laminating 30 nm of aluminum chelate (Alq3). The host material of the organic light emitting layer (30 nm) is 4,4′-bis (2,2′-diphenylvinyl) biphenyl (DPVBi), and the guest is 4,4′-bis [2- {4- (N, N-diphenyl). Amino) phenyl} vinyl] biphenyl (DPAVBi). The hole transport layer was formed by laminating 40 nm of 4,4′-bis [N- (1-naphthyl) -N-phenylamino] biphenyl (α-NPD).

  Next, two layers of IZO were laminated as an upper transparent electrode by sputtering. The sputtering gas at this time was Ar. The IZO of the first transparent conductive layer 14 was formed with a DC power of 150 W and a film thickness of 200 nm, and the IZO of the second transparent conductive layer 15 was formed with a DC power of 100 W and a film thickness of 300 nm. The refractive index of the first transparent conductive layer 14 was 2.1, and the refractive index of the second transparent conductive layer 15 was 1.9. Thus, the organic EL element part 1 (backlight) was obtained.

  After applying a resist agent “OFRP-800” (trade name, manufactured by Tokyo Ohka Kogyo Co., Ltd.) on the second transparent conductive layer 15, patterning is performed by a photolithography method, and the width is 0.204 mm and the stripe is located in the red sub-pixel. An opening 16 made of a pattern was formed. The depth of the opening by etching is 300 nm.

  Next, the substrate on which the above structure was formed was conveyed into a vapor deposition apparatus, and a color conversion layer 17 composed of coumarin 6 and DCM-2 was produced. That is, the color conversion layer 17 having a film thickness of 200 nm was produced by co-evaporation in which coumarin 6 and DCM-2 were heated in separate crucibles in the vapor deposition apparatus. At this time, the heating temperature of each crucible was controlled so that the deposition rate of coumarin 6 was 0.3 nm / s and the deposition rate of DCM-2 was 0.005 nm / s. The color conversion layer 17 of this example contained 2 mol% of DCM-2 based on the total number of molecules constituting the color conversion layer 17 (coumarin 6: DCM-2 molar ratio is 49: 1).

Next, using a plasma CVD method using monosilane (SiH ₄ ), nitrogen (N ₂ ), and ammonia (NH ₃ ) as a source gas, silicon nitride (SiN _x ) having a film thickness of 300 nm so as to cover the color conversion layer 17. Then, the protective layer 18 was formed. Here, when depositing SiN _x , the temperature of the stacked body on which the color conversion layer 17 was formed was maintained at 100 ° C. or lower.

  Next, the cellophane tape prescribed | regulated to JISZ1522 was affixed on the non-opening part, and the laminated body of the color conversion layer 17 and the protective film 18 was peeled. Before peeling, a femtosecond laser with a spot size of 15 μm (CPA-2001 made by Clark-MXR) is applied to the peripheral edge of the opening, the thin film with a width of 20 μm is removed, and the film on the opening and the non-opening The upper membrane was separated.

The manufacturing method of the color filter substrate was performed as follows.
A resist resin containing a black dye is applied on a Corning glass 21 (50 mm × 50 mm × 1.1 mm) as a transparent substrate 21 by spin coating, patterning is performed by photolithography, and openings for forming color filters A black matrix having a thickness of 2 μm was formed, leaving the portion.

[Production of blue filter]
After applying blue filter material (Fuji Hunt Electronics Technology: Color Mosaic CB-7001) by spin coating method, patterning by photolithography method, blue filter 22 line width 0.134mm, pitch 1.014mm, film A line pattern with a thickness of 6 μm was obtained.

[Production of green filter]
After applying green filter material (Fuji Hunt Electronics Technology: color mosaic CG-7001) by spin coating method, patterning is performed by photolithography method, green filter 23 line width 0.134mm, pitch 1.01mm, film A line pattern with a thickness of 6 μm was obtained.

[Production of red filter layer]
A red filter material (Fuji Hunt Electronics Technology: Color Mosaic CR-7001) is applied by spin coating, and then patterned by photolithography, and the red filter 24 has a line width of 0.134 mm, a pitch of 1.01 mm, and a film. A line pattern with a thickness of 6 μm was obtained.

  The organic EL device 1 obtained as described above is moved to a nitrogen-substituted glove box without being exposed to the atmosphere, and is adhered to the color filter substrate 2 in an atmosphere of 1 ppm or less of both moisture and oxygen, and the organic EL display Was completed. In the obtained display, the color conversion layer 17 does not remain on the second transparent conductive layer 15, and the color conversion layer 17 is formed in close contact with the entire surface of the first transparent conductive layer 14 in the opening 16. The protective layer 18 was formed on the entire surface of the color conversion layer 17 on the color conversion layer 17 in the opening 16.

  The reflectance at the upper transparent electrode of the obtained display could be suppressed to 3%, and the output of the organic EL element was improved by 15%. In addition, since the red light emission can use the color conversion layer formed by the vapor deposition method patterned by this method, the light emission efficiency can be improved from 0.8 cd / A to 1.5 cd / A.

(Example 2)
In the production of the organic EL element, instead of peeling off the laminate of the color conversion layer 17 and the protective film 18, tape peeling was performed after the color conversion layer 17 was produced, and then the protective layer 18 was formed. Thus, an organic EL display was produced. In this case, since the color conversion layer is in the concave portion of the opening, it does not come into contact with the tape. Therefore, only the color conversion layer 17 on the non-opening is peeled off without problems even without processing the periphery of the opening with a femtosecond laser. did it. Therefore, in Example 2, as well as Example 1, no color conversion layer remains on the second transparent conductive layer, and the color conversion layer adheres in the opening so as to cover the entire surface of the first transparent conductive layer. A protective layer was formed in close contact with the color conversion layer in the opening so as to cover the entire surface of the color conversion layer.
The reflectance of the upper transparent electrode of the obtained display, the output improvement of the organic EL element, and the efficiency improvement were the same as those of the display of Example 1.

It is a figure which shows the structure of the top emission type organic EL element of this invention. It is a figure which shows the manufacturing process in the 1st Embodiment of this invention. It is a figure which shows the manufacturing process in the 2nd Embodiment of this invention. It is a figure which shows an example of the process of forming a color conversion layer and a protective layer in an opening part in this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Organic EL element part 2 Color filter board | substrate 11 Board | substrate 12 Lower reflective electrode 13 Organic EL layer 14 1st transparent conductive layer 15 2nd transparent conductive layer 16 Opening part 17 Color conversion layer 18 Protective layer 19 Insulating film 21 Transparent substrate (filter board | substrate) )
22 (R, G, B) Color filter layer (red, green, blue)
30 Light from light emitting part (a: not converted, c: converted by color conversion layer 17)
40 (R, G, B) Output light (red, green, blue)

Claims (7)

  The transparent electrode provided in contact with the organic EL layer of the organic EL element unit to be bonded to the color filter substrate is composed of two layers of the first transparent conductive layer and the second transparent conductive layer from the organic EL layer side, and the first transparent conductive layer The refractive index of the second transparent conductive layer is larger than the refractive index of the second transparent conductive layer, and the second transparent conductive layer is provided with an opening in a region facing at least one type of filter portion of the color filter. And forming a color conversion layer that converts light emitted from the light emitting layer into light containing visible light having a longer wavelength than the depth of the opening, and then a second transparent conductive layer other than the opening. A method for producing an organic EL display, comprising peeling off the upper color conversion layer with a pressure-sensitive adhesive tape.   2. The method of manufacturing an organic EL display according to claim 1, wherein a protective layer is formed after peeling with the pressure-sensitive adhesive tape.   The method for producing an organic EL display according to claim 1, wherein after the protective layer is formed on the color conversion layer, the color conversion layer and the protective layer other than the opening are peeled off by the pressure-sensitive adhesive tape.   4. The method of manufacturing an organic EL display according to claim 3, wherein the total film thickness of the color conversion layer and the protective layer is formed to be thicker than the depth of the opening.   4. The device according to claim 3, wherein after the formation of the protective layer and before the peeling with the pressure-sensitive adhesive tape, the periphery of the opening is irradiated with an energy beam to separate the opening and other than the opening. 4. A method for producing an organic EL display according to 4.   6. The method of manufacturing an organic EL display according to claim 5, wherein the energy beam is a femtosecond laser.   The method for manufacturing an organic EL display according to claim 1, wherein a region where the opening is provided is opposed to a red filter portion of the color filter substrate.

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