JP2010118191A - Organic electroluminescent display device and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an organic electroluminescent display device capable of preventing damage due to a mask for film formation and degradation of image quality; and a manufacturing method of the same. <P>SOLUTION: The organic electroluminescent display device 1 includes an insulating substrate 3, a plurality of organic electroluminescent elements 4 formed on the insulating substrate 3, and an insulating film formed on the insulating substrate 3 to demarcate the plurality of organic electroluminescent elements 4 from one another. The organic electroluminescent elements 4 each include a first electrode 6, an organic layer 7 formed on the first electrode 6 and including a light-emitting layer, and a second electrode 8 which is formed on the organic layer 7. On the insulating film 5, a plurality of ribs 14 are provided projecting from a surface 5a of the insulating film 5 in a thickness direction Y of the organic electroluminescent display device 1, and the plurality of electroluminescent elements 4 are each formed between adjacent ones of the ribs 14. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an organic EL display device including an organic EL panel having an organic electroluminescence element (organic electroluminescence element: hereinafter referred to as “organic EL element”), and a method for manufacturing the same.

  In recent years, organic EL display devices have attracted attention as next-generation flat panel display devices. This organic EL display device is a self-luminous display device, has excellent viewing angle characteristics, high visibility, low power consumption, and can be reduced in thickness, so that demand is increasing.

  The organic EL display device includes a plurality of organic EL elements arranged in a predetermined arrangement, and each of the plurality of organic EL elements includes a first electrode formed on an insulating substrate and a first electrode. The organic layer which has the formed light emitting layer, and the 2nd electrode formed on the organic layer are provided.

  In general, a vapor deposition method is known as a method for forming an organic EL thin film used in the organic EL display device on a substrate. In this vapor deposition method, first, the substrate is placed in a horizontal state with the surface to be deposited on the lower side, and a metal mask is brought into close contact with the substrate surface. Next, an organic EL thin film having a predetermined pattern is formed on the surface of the substrate by evaporating an evaporation material (that is, an organic EL material) from the evaporation source provided below the substrate surface through a mask opening in which the predetermined pattern is formed. I am letting.

  Here, in the above vapor deposition method, when forming each pixel region (or light emitting region) of R (red), G (green), and B (blue), the mask is in close contact with the substrate surface, It is necessary to move the mask on the surface of the first electrode or organic EL element formed on the insulating substrate. Further, in order to perform alignment with the substrate, it is necessary to move the mask by a minute distance (about several tens of μm) in a state where the mask is in close contact with the substrate surface. Therefore, with the movement of the mask, the first electrode and the organic EL element formed on the substrate are damaged, resulting in a problem that the yield is lowered.

Therefore, an organic EL element for preventing damage due to such a film-forming mask has been proposed. More specifically, an insulating film is formed so as to surround the pixel region, and a certain space is secured in the pixel region with respect to a mask used when an organic layer is formed in the pixel region. An organic EL element provided with a spacer is disclosed. And it is described that, with such a configuration, when the organic layer is formed, contact between the mask and the organic layer can be avoided, so that a light emitter can be formed satisfactorily without being damaged by the mask. (For example, refer to Patent Document 1).
JP 2003-59671 A

  However, in the organic EL element described in Patent Document 1, damage due to the mask can be avoided, but when forming each pixel region of R (red), G (green), and B (blue), Due to factors such as the alignment accuracy between the substrate and the mask, the finished dimensional accuracy of the mask itself, the adhesion between the substrate and the mask, and the positional accuracy of the mask when the mask is brought into close contact with the substrate surface, the adjacent pixel regions have different colors. There has been a problem in that the light emitting material is mixed to cause a mixture of light emission colors (that is, color mixture) between display pixels, and the image quality is significantly deteriorated.

  In addition, as described above, since it is necessary to provide a spacer in the pixel region, when the organic layer is formed, the spacer serves as a barrier in the vicinity of the spacer in the pixel region, has a uniform film distribution, and is efficient. It has been difficult to form an organic layer having a film thickness necessary for light emission. As a result, defective pixels are generated and the image quality is significantly lowered.

  Furthermore, since it is necessary to provide a spacer in the pixel region, the aperture ratio is lowered, and as a result, there is a problem that the luminance is lowered and a good image quality cannot be obtained.

  Accordingly, the present invention has been made in view of the above-described problems, and provides an organic EL display device and a method for manufacturing the same that can prevent damage caused by a film-formation mask and prevent deterioration in image quality. For the purpose.

  In order to achieve the above object, an invention according to claim 1 is directed to an insulating substrate, a first electrode formed on the insulating substrate, an organic layer formed on the first electrode and having a light emitting layer. Organic EL display device comprising: a plurality of organic EL elements having a layer and a second electrode formed on the organic layer; and an insulating film that is formed on the insulating substrate and partitions the plurality of organic EL elements On the insulating film, a plurality of ribs projecting from the surface of the insulating film in the thickness direction of the organic EL display device are provided, and each of the plurality of organic EL elements is formed between the ribs. It is characterized by that.

  According to this configuration, when the organic layer is formed on the first electrode using the deposition mask by vapor deposition, the mask and the first electrode can be adhered to the surface of the rib. , And contact between the mask and the organic layer provided on the surface of the first electrode can be prevented. Therefore, damage due to the film-formation mask can be prevented, so that an organic EL display device capable of preventing a decrease in yield can be provided.

  In addition, since each of the plurality of organic EL elements is formed between the ribs, when forming each pixel region, it is possible to prevent light emitting materials of different colors from being mixed into adjacent pixel regions. It becomes possible. Therefore, it is possible to provide an organic EL display device that can prevent color mixing and, as a result, can prevent deterioration in image quality.

  Further, unlike the above-described conventional technique, it is not necessary to provide a spacer in the pixel region, so that it is possible to form an organic layer having a uniform film distribution and a film thickness necessary for efficient light emission. Therefore, since an occurrence of defective pixels can be prevented, an organic EL device that can prevent deterioration in image quality can be provided. Further, since it is not necessary to provide a spacer in the pixel region, it is possible to prevent the aperture ratio from being lowered. Therefore, it is possible to provide an organic EL display device that can prevent a decrease in luminance and obtain good image quality.

  A second aspect of the present invention is the organic EL display device according to the first aspect, wherein the insulating film is formed so as to cover a peripheral portion of the first electrode.

  According to this configuration, since the occurrence of the shadow phenomenon can be prevented, a short circuit between the first electrode and the second electrode can be avoided, and the occurrence of leakage current can be prevented. As a result, it is possible to prevent a decrease in light emission efficiency of the element.

  The “shadow phenomenon” as used herein means that when the organic layer is formed on the first electrode by a vapor deposition method on the first electrode, the peripheral portion of the first electrode in the mask opening is This is a phenomenon in which the film thickness at the periphery of the organic layer becomes thinner than the film thickness at the center, behind the mask.

  The invention according to claim 3 is the organic EL display device according to claim 1 or 2, wherein the insulating film and the rib are integrally formed of the same material. .

  According to this configuration, an organic EL display device with a simplified manufacturing process can be provided.

  The invention according to claim 4 is the organic EL display device according to any one of claims 1 to 3, wherein the rib has a thickness of 1 μm or more and 50 μm or less.

  According to this configuration, even when the rib is provided, it is possible to cope with the thinning of the organic EL display device, and the first electrode is formed on the first electrode by using the deposition mask by the vapor deposition method. An organic EL display device capable of reliably preventing contact between the mask and the first electrode and the organic layer provided on the surface of the mask and the first electrode when forming the organic layer on the surface. it can.

  The invention according to claim 5 is the organic EL display device according to any one of claims 2 to 4, wherein the insulating film has a thickness of 0.2 μm or more and 1.0 μm or less. Features.

  According to this configuration, it is possible to prevent a reduction in the light emission efficiency of the element due to the occurrence of leakage current without causing interference such as color mixing between adjacent pixel regions.

  According to a sixth aspect of the invention, there is provided an organic EL display device comprising a plurality of organic EL elements in which a first electrode, an organic layer having a light emitting layer, and a second electrode are formed in this order on an insulating substrate. A method comprising: forming a plurality of first electrodes on an insulating substrate; forming an insulating film that partitions the plurality of first electrodes on the insulating substrate; and insulating the insulating film on the insulating film. Forming a plurality of ribs protruding in the thickness direction of the organic EL display device from the surface of the film, disposing each of the plurality of first electrodes between the ribs, and providing a mask on the surface of the ribs; The method includes at least a step of closely attaching the mask to the rib and a step of forming an organic layer on the first electrode and a second electrode on the organic layer using the mask.

  According to this configuration, when the organic layer is formed on the first electrode using the film formation mask, the mask and the first electrode, and the mask and the first electrode are adhered to the surface of the rib. The contact with the organic layer provided on the surface of can be prevented. Therefore, damage due to the mask for film formation can be prevented, so that a reduction in the yield of the organic EL display device can be prevented.

  In addition, since each of the plurality of organic EL elements is formed between the ribs, it is possible to prevent light emitting materials of different colors from being mixed into adjacent pixel regions when forming each pixel region. become. Therefore, the occurrence of color mixing can be prevented, so that the image quality can be prevented from deteriorating.

  Further, unlike the above-described conventional technique, since it is not necessary to provide a spacer in the pixel region, the organic layer has a uniform film distribution and a film thickness necessary for efficient light emission when forming the organic layer. Can be formed. Therefore. Since the occurrence of defective pixels can be prevented, the image quality can be prevented from deteriorating. Further, since it is not necessary to provide a spacer in the pixel region, it is possible to prevent the aperture ratio from being lowered. Accordingly, it is possible to prevent a decrease in luminance and obtain a good image quality.

  A seventh aspect of the present invention is the method of manufacturing the organic EL display device according to the sixth aspect, wherein an insulating film is formed so as to cover a peripheral portion of the first electrode.

  According to this configuration, since the occurrence of the shadow phenomenon can be prevented, a short circuit between the first electrode and the second electrode can be avoided, and the occurrence of leakage current can be prevented. As a result, it is possible to prevent a decrease in light emission efficiency of the element.

  The invention according to claim 8 is the method for manufacturing the organic EL display device according to claim 6 or 7, wherein the insulating film and the rib are formed simultaneously.

  According to this configuration, the manufacturing process of the organic EL display device can be simplified.

A ninth aspect of the invention is a method of manufacturing an organic EL display device according to the eighth aspect of the invention, wherein the insulating film and the rib are integrally formed of the same material.
According to this configuration, the manufacturing process of the organic EL display device can be further simplified.

  The invention according to claim 9 is the method for manufacturing the organic EL display device according to claim 9, wherein the material is a photosensitive material, and the photosensitive material is applied with a plurality of exposure masks having different exposure patterns. Insulating films and ribs are formed by multiple exposure for sequential exposure.

  According to this configuration, the insulating film and the rib can be formed with high accuracy.

  Invention of Claim 11 is a manufacturing method of the organic electroluminescence display device of any one of Claims 6-10, Comprising: Thickness of a rib is formed in 1 micrometer or more and 50 micrometers or less, It is characterized by the above-mentioned. And

  According to this configuration, even when the rib is provided, it is possible to cope with the thinning of the organic EL display device, and the first electrode is formed on the first electrode by using the deposition mask by the vapor deposition method. When the organic layer is formed, contact between the mask and the first electrode and between the mask and the organic layer provided on the surface of the first electrode can be reliably prevented.

  The invention described in claim 12 is the method of manufacturing an organic EL display device according to any one of claims 6 to 11, wherein the insulating film has a thickness of 0.2 μm or more and 1.0 μm or less. It is characterized by forming.

  According to this configuration, it is possible to prevent a reduction in the light emission efficiency of the element due to the occurrence of leakage current without causing interference such as color mixing between adjacent pixel regions.

  ADVANTAGE OF THE INVENTION According to this invention, the damage by the mask for film-forming can be prevented, and the fall of the yield of an organic electroluminescence display can be prevented. Further, it is possible to prevent the occurrence of color mixing and to prevent the image quality from deteriorating.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. The present invention is not limited to the following embodiment.

  FIG. 1 is a plan view of an organic EL display device according to an embodiment of the present invention, and FIG. 2 is a cross-sectional view taken along line AA of FIG. FIG. 3 is a cross-sectional view for explaining an organic layer constituting the organic EL element included in the organic EL display device according to the embodiment of the present invention, and FIG. 4 is an organic EL according to the embodiment of the present invention. It is a top view for demonstrating arrangement | positioning of the insulating film with which a display apparatus is provided.

  As shown in FIG. 1, in the organic EL display device 1, a pixel region 2R that emits red light, a pixel region 2G that emits green light, and a pixel region 2B that emits blue light are arranged according to a predetermined pattern. . An insulating film 5 is provided between the pixel regions 2R, 2G, and 2B to partition the pixel regions 2R, 2G, and 2B.

  As shown in FIG. 2, the organic EL display device 1 includes an insulating substrate 3, a plurality of organic EL elements 4 provided on the surface of the insulating substrate 3 at predetermined intervals, and an organic EL element 4. An insulating film 5 is provided between each of the plurality of organic EL elements 4.

  The insulating substrate 3 is formed of an insulating material such as glass or plastic.

  As shown in FIG. 2, the organic EL element 4 includes a first electrode 6 (anode) provided on the surface of the insulating substrate 3, and an organic layer 7 provided on the surface of the first electrode 6. And a second electrode 8 (cathode) provided on the surface of the organic layer 7.

  A plurality of first electrodes 6 are formed in a matrix at predetermined intervals on the surface of the insulating substrate 3, and each of the plurality of first electrodes 6 is provided in each pixel region 2R, 2G, 2B is configured. The first electrode 6 is made of, for example, Au, Ni, Pt, ITO (indium-tin oxide), or the like.

  The organic layer 7 is formed on the surface of each first electrode 6 partitioned in a matrix. As shown in FIG. 3, the organic layer 7 is formed on the hole injection layer 9, the hole transport layer 10 formed on the surface of the hole injection layer 9, and the surface of the hole transport layer 10. , A light emitting layer 11 that emits one of red light, green light, and blue light, an electron transport layer 12 formed on the surface of the light emitting layer 11, and an electron injection layer formed on the surface of the electron transport layer 12 13. And the organic layer 7 is comprised by laminating | stacking these hole injection layer 9, the hole transport layer 10, the light emitting layer 11, the electron transport layer 12, and the electron injection layer 13 one by one.

  The hole injection layer 9 is for increasing the efficiency of hole injection into the light emitting layer 11. Examples of the material for forming the hole injection layer 9 include benzine, styrylamine, triphenylamine, porphyrin, triazole, imidazole, oxadiazole, polyarylalkane, phenylenediamine, arylamine, oxazole, anthracene, fluorenone, Examples include hydrazone, stilbene, triphenylene, azatriphenylene, or derivatives thereof, or heterocyclic conjugated monomers, oligomers, or polymers such as polysilane compounds, vinylcarbazole compounds, thiophene compounds, or aniline compounds. .

  The hole transport layer 10 is for increasing the efficiency of hole injection into the light emitting layer 11, as with the hole injection layer 9 described above. The thing similar to the hole injection layer 9 can be used.

  The light emitting layer 11 is a region in which holes and electrons are injected from each of both electrodes and a hole and an electron are recombined when a voltage is applied by the first electrode 6 and the second electrode 8. The light emitting layer 11 is formed of a material having high luminous efficiency, and is formed of, for example, an organic material such as a low molecular fluorescent dye, a fluorescent polymer, or a metal complex. More specifically, for example, anthracene, naphthalene, indene, phenanthrene, pyrene, triphenylene, perylene, picene, fluoranthene, acephenanthrylene, pentaphen, pentacene, coronene, butadiene, coumarin, acridine, stilbene, or derivatives thereof, Examples include tris (8-quinolinolato) aluminum complex, bis (benzoquinolinolato) beryllium complex, and tri (dibenzoylmethyl) phenanthroline europium complex ditoluyl vinyl biphenyl.

  The electron transport layer 12 is for transporting electrons injected from the second electrode 8 to the light emitting layer 11. Examples of the material forming the electron transport layer 12 include quinoline, perylene, phenanthroline, bisstyryl, pyrazine, triazole, oxazole, oxadiazole, fluorenone, and derivatives or metal complexes thereof. More specifically, tris (8-hydroxyquinoline) aluminum, anthracene, naphthalene, phenanthrene, pyrene, anthracene, perylene, butadiene, coumarin, acridine, stilbene, 1,10-phenanthroline, or a derivative or metal complex thereof may be mentioned. .

  The electron injection layer 13 is for transporting electrons injected from the second electrode 8 to the light emitting layer 11, similarly to the electron transport layer 12 described above, and the material for forming the electron injection layer 13 is described above. The same material as the electron transport layer 12 can be used.

  The second electrode 8 has a function of injecting electrons into the organic layer 7. The second electrode 8 is made of, for example, a magnesium alloy (such as MgAg), an aluminum alloy (such as AlLi, AlCa, or AlMg), metallic calcium, or a metal having a small work function.

  The insulating film 5 is provided on the surface of the insulating substrate 3 and partitions each of the plurality of adjacent first electrodes 6. Examples of the material for forming the insulating film 5 include insulating resin materials such as photosensitive polyimide resin, acrylic resin, methallyl resin, or novolac resin.

  Further, as shown in FIGS. 2 and 4, the insulating film 5 is formed on the insulating substrate 3 so as to cover the peripheral edge 6 a of the first electrode 6. With such a configuration, it is possible to prevent a short circuit between the first electrode 6 and the second electrode 8 and avoid the occurrence of a leakage current.

  That is, in general, when an organic layer is formed on the first electrode by a vapor deposition method on the first electrode, the periphery of the first electrode in the mask opening is behind the mask, and the organic layer A phenomenon (so-called shadow phenomenon) occurs in which the film thickness at the peripheral edge of the film becomes thinner than the film thickness at the center. When the shadow phenomenon occurs, the current concentrates in a thin film thickness, or the first electrode and the second electrode are short-circuited through the thin film. As a result, a leakage current is generated, thereby improving the light emission efficiency of the device. A decline will occur.

  On the other hand, in the present embodiment, as described above, since the insulating film 5 is formed so as to cover the peripheral portion 6a of the first electrode 6, the occurrence of the shadow phenomenon can be prevented. Therefore, a short circuit between the first electrode 6 and the second electrode 8 can be avoided, and the occurrence of leakage current can be prevented.

The thickness _{T 1} of the insulating film 5 is not particularly limited, but is preferably 0.2μm or more 1.0μm or less. If this is less than the thickness T ₁ of the insulating film 5 is 0.2 [mu] m, and in some cases the disadvantage that it is difficult to prevent the occurrence of a leakage current occurs, when 1.0μm greater than, This is because the light generated in the organic EL element 4 propagates through the insulating layer 5 to cause interference such as mixing of emission colors between the adjacent pixel regions 2R, 2G, and 2B.

  Here, in the present embodiment, when the organic layer 7 is formed on the first electrode 6 by using a deposition mask 16 (see FIGS. 8 to 11 described later) by vapor deposition, the mask is used. It is characterized in that ribs 14 serving as spacers between 16 and the first electrode 6 and between the mask 16 and the organic layer 7 are provided. More specifically, as shown in FIGS. 1 and 2, in the organic EL display device 1, the thickness direction of the organic EL display device 1 (that is, the organic EL device) is formed on the insulating film 5 from the surface 5 a of the insulating film 5. A plurality of ribs 14 projecting in the direction perpendicular to the surface direction X of 1 and in the direction of arrow Y in FIG. 2 are provided. Each of the plurality of organic EL elements 4 is formed between these ribs 14.

  With such a configuration, as will be described later, when the organic layer 7 is formed on the first electrode 6 using the deposition mask 16 by vapor deposition, the mask 16 is brought into close contact with the surface 14a of the rib 14. Therefore, contact between the mask 16 and the first electrode 6 and between the mask and the organic layer 7 provided on the surface of the first electrode 6 can be prevented.

  In addition, since each of the plurality of organic EL elements 4 formed in each pixel region 2R, 2G, 2B is formed between the ribs 14, adjacent to each other when forming each pixel region 2R, 2G, 2B. It is possible to prevent light emitting materials of different colors from entering the pixel area.

  In addition, unlike the above-described prior art, it is not necessary to provide a spacer in the pixel region. Therefore, when the organic layer 7 is formed, the organic layer 7 has a uniform film distribution and a film thickness necessary for efficient light emission. The layer 7 can be formed, and the aperture ratio can be prevented from decreasing.

  As a material for forming the rib 14, the same material as that of the insulating film 5 described above can be used. For example, an insulating resin material such as photosensitive polyimide resin, acrylic resin, methallyl resin, or novolac resin can be used. Can be mentioned. Further, when the insulating film 5 and the rib 14 are formed of the same insulating resin material, the insulating film 5 and the rib 14 can be formed integrally. In the present embodiment, as shown in FIG. 2, a rib 14 having a substantially rectangular cross section is provided.

The thickness _{T 2} of the ribs 5 is not particularly limited, but is preferably 1μm or more 50μm or less. This is because when the thickness T ₂ of the rib 5 is less than 1 μm, when the organic layer 7 is formed on the first electrode 6 using the mask 16, the mask 16 adhered to the surface 14 a of the rib 14 is This is because inconvenience may occur that the first electrode 6 and the organic layer 7 are approached. When the thickness is larger than 50 μm, the mask 16 and the first electrode 6 and the mask 16 and the first electrode 6 are provided on the surface. This is because although the contact with the organic layer 7 can be reliably prevented, the thickness of the organic EL display device 1 becomes large, and it may be difficult to reduce the thickness of the device.

  Next, an example of a method for manufacturing the organic EL display device of the present embodiment will be described. 5 to 10 are cross-sectional views for explaining a method of manufacturing an organic EL display device according to an embodiment of the present invention.

  First, as shown in FIG. 5, an ITO film is patterned by sputtering on an insulating substrate 3 such as a glass substrate having a substrate size of 300 × 400 mm and a thickness of 0.7 mm. The electrode 6 is formed. At this time, the film thickness of the first electrode 6 is, for example, about 150 nm.

  Next, as shown in FIG. 6, a positive photosensitive polyimide resin is applied on the insulating substrate 3 by a spin coating method. Thereafter, a part of the first electrode 6 is exposed by a photolithography method, and firing is performed under predetermined conditions (for example, at a temperature of 100 ° C. for 3 minutes), so that each pixel region 2R, 2G, 2B is exposed. The structure 15 is patterned. The film thickness of the structure 15 is, for example, 5 μm. Further, although the structure 13 is formed by a photolithography method, it may be formed by, for example, a transfer method or a printing method.

Subsequently, the structure 13 is subjected to multiple exposure for continuous exposure, whereby the insulating film 5 and the ribs 14 are integrally formed of the same insulating resin material (that is, photosensitive polyimide resin). . More specifically, first, two exposure masks having different exposure patterns are prepared, and an exposure mask having an exposure pattern in which a light-shielding portion is provided only in a region corresponding to the insulating film 5 is used. The first exposure for forming the insulating film 5 is performed with an exposure amount (for example, 300 mJ / cm ₂ ). Next, a second time for forming the rib 14 with a predetermined exposure dose (for example, 150 mJ / cm ₂ ) using an exposure mask having an exposure pattern in which a light-shielding portion is provided only in a region corresponding to the rib 14. Exposure. That is, the cumulative exposure amount for the photosensitive polyimide resin is made different for each region by multiple exposure in which the photosensitive polyimide resin is sequentially exposed with two exposure masks having different exposure patterns.

  Next, development processing is performed on the photosensitive polyimide resin using a developer (for example, tetramethylammonium hydroxide solution). Then, the photosensitive polyimide resin is removed according to the exposure amount, and the insulating film 5 and the plurality of ribs 14 are integrally formed with the photosensitive polyimide resin as shown in FIG.

  Thus, in this embodiment, since the insulating film 5 and the rib 14 are formed simultaneously, the manufacturing process of the organic EL display device 1 can be simplified. Moreover, since the insulating film 5 and the rib 14 are formed by multiple exposure as described above, the insulating film 5 and the rib 14 can be formed with high accuracy.

The insulating film 5 is formed so as to partition the plurality of first electrodes 6 and so as to cover the peripheral edge 6 a of the first electrode 6. Each of the plurality of first electrodes 6 is disposed between the ribs 14. The ribs 14 are formed on the insulating film 5 so as to protrude from the surface 5a of the insulating film 5 in the thickness direction Y of the organic EL display device. The thickness _{T 1} of the insulating film 5 is formed, for example, 0.5 [mu] m, the thickness _{T 2} of the rib 14 is formed, for example, 4.5 [mu] m.

  Next, the organic layer 7 including the light emitting layer 11 and the second electrode 8 are formed on the first electrode 6 by vapor deposition using a metal mask 16.

More specifically, first, the insulating substrate 3 provided with the insulating film 5, the first electrode 6, and the rib 14 is placed in the chamber of the vapor deposition apparatus. Note that the inside of the chamber of the vapor deposition apparatus is kept at a vacuum degree of 1 × 10 ⁻⁵ to 1 × 10 ⁻⁴ (Pa) by a vacuum pump. The insulating substrate 3 provided with the insulating film 5, the first electrode 6, and the rib 14 is installed in a state where two sides are fixed by a pair of substrate receivers attached in the chamber.

  Next, as shown in FIG. 8, a metal mask 16 is provided on the surface 14 a of the rib 14, and the mask 16 is brought into close contact with the surface 14 a of the rib 14. At this time, the mask 16 is positioned and positioned so that the opening 16a corresponds to the pixel region 2R that emits red light. As the mask 16, for example, a mask obtained by laser welding an invar mask having a thickness of about 40 μm to an invar frame having a thickness of about 8 mm can be used.

  The alignment between the insulating substrate 3 and the mask 16 is performed by recognizing two alignment marks provided on the insulating substrate 3 and the mask 16 with a CCD camera incorporated in the vapor deposition apparatus. The recognition of the alignment mark is first repeated until the positional error between the alignment marks is within ± 2 μm without contacting the rib 14 and the mask 16. Subsequently, the alignment mark recognition is completed when the position error between the alignment marks is within ± 5 μm in a state where the rib 14 and the mask 16 are completely adhered. If the positional error between the alignment marks does not fall within ± 5 μm with the ribs 14 and the mask 16 being in close contact, the process is repeated from the state where the ribs 14 and the mask 16 are not in contact with each other.

  Next, the four corners of the mask 16 in close contact with the ribs 14 are fixed with a mask receiver in the chamber.

  Then, the vapor deposition materials of the hole injection layer 9, the hole transport layer 10, the light emitting layer 11, the electron transport layer 12, and the electron injection layer 13 are sequentially evaporated from the vapor deposition source, so that the hole injection layer 9, the hole By laminating the transport layer 10, the light emitting layer 11, the electron transport layer 12, and the electron injection layer 13, as shown in FIG. 8, the organic layer 7 is formed in the pixel region 2R. At this time, as shown in FIG. 8, a sufficient distance is secured between the mask 16 adhered to the surface 14 a of the rib 14 and the first electrode 6 and the organic layer 7. Contact between the first electrode 6 and the organic layer 7 does not occur. Further, the rib 14 can prevent the red light emitting material from being mixed into the adjacent pixel region 2G.

  Next, as shown in FIG. 9, alignment is performed so that the opening 16a of the mask 16 in close contact with the surface 14a of the rib 14 corresponds to the pixel region 2G that emits green light. Also in this case, as shown in FIG. 9, a sufficient distance is secured between the mask 16 adhered to the surface 14 a of the rib 14 and the first electrode 6 and the organic layer 7. Contact between the first electrode 6 and the organic layer 7 does not occur. Then, the vapor deposition materials of the hole injection layer 9, the hole transport layer 10, the light emitting layer 11, the electron transport layer 12, and the electron injection layer 13 are sequentially evaporated from the vapor deposition source, so that the hole injection layer 9, the hole By laminating the transport layer 10, the light emitting layer 11, the electron transport layer 12, and the electron injection layer 13, as shown in FIG. 9, the organic layer 7 is formed in the pixel region 2G. At this time, the rib 14 prevents the green light emitting material from being mixed into the adjacent pixel regions 2R and 2B.

  Next, as shown in FIG. 10, alignment is performed so that the opening 16a of the mask 16 in close contact with the surface 14a of the rib 14 corresponds to the pixel region 2B that emits blue light. Also in this case, as shown in FIG. 10, a sufficient distance is secured between the mask 16 adhered to the surface 14 a of the rib 14 and the first electrode 6 and the organic layer 7. Contact between the first electrode 6 and the organic layer 7 does not occur. Then, the vapor deposition materials of the hole injection layer 9, the hole transport layer 10, the light emitting layer 11, the electron transport layer 12, and the electron injection layer 13 are sequentially evaporated from the vapor deposition source, so that the hole injection layer 9, the hole By laminating the transport layer 10, the light emitting layer 11, the electron transport layer 12, and the electron injection layer 13, as shown in FIG. 10, the organic layer 7 is formed in the pixel region 2B. At this time, the rib 14 prevents the blue light emitting material from being mixed into the adjacent pixel region 2G.

  Then, by forming the second electrode 8 on the organic layer 7 using the mask 16, a plurality of organic EL elements 7 are formed between the ribs 14, and the organic EL display device 1 shown in FIG. Will be.

  As described above, in the present embodiment, since each of the plurality of organic EL elements 7 is formed between the ribs 14, it is possible to prevent the light emitting materials of different colors from being mixed into the adjacent pixel regions by the ribs 14. .

  As an evaporation source, for example, a crucible charged with each evaporation material can be used. The crucible is installed in the lower part of the chamber, and the crucible is equipped with a heater, and the crucible is heated by the heater. And when the internal temperature of a crucible reaches the evaporation temperature of various vapor deposition materials by the heating by a heater, the various vapor deposition materials prepared in the crucible become evaporation molecules and jump out upward in the chamber.

  In addition, the evaporation rate of evaporated molecules (film thickness deposited per unit time) is monitored by a quartz oscillator installed in the chamber, and can be opened and closed installed in the chamber until the evaporation rate stabilizes. The shutter is prevented from being deposited on the insulating substrate 3. Then, when the evaporation rate of various vapor deposition materials is stabilized at a desired value, the shutter is opened, and various evaporated molecules jumping out from the crucible are attached to the surface of the insulating substrate 3 through the openings 16a of the mask 16 to form an organic layer. 7 and the second electrode 8 are formed.

  As a specific example of the formation of the organic layer 7 and the second electrode 8, first, on the first electrode 6 patterned on the insulating substrate 3, m-MTDATA ( A hole injection layer 9 made of 4,4,4-tris (3-methylphenylphenylamino) triphenylamine) is formed with a film thickness of, for example, 25 nm through a mask 16. Subsequently, a hole transport layer 10 made of α-NPD (4,4-bis (N-1-naphthyl-N-phenylamino) biphenyl) is formed on the hole injection layer 9 in common to all pixels of RGB. For example, the film is formed with a film thickness of 30 nm through the mask 16. Next, as red light emitting layer 11, 30 weight of 2,6-bis ((4'-methoxydiphenylamino) styryl) -1,5-dicyanonaphthalene (BSN) is added to di (2-naphthyl) anthracene (ADN). % Mixed material is formed with a film thickness of, for example, 30 nm on the hole transport layer 10 formed in the pixel region 2 </ b> R through the mask 16. Next, a green light-emitting layer 11 in which 5% by weight of coumarin 6 is mixed with ADN is deposited on the hole transport layer 10 formed in the pixel region 2G through the mask 16 with a film thickness of, for example, 30 nm. Form. Next, the blue light-emitting layer 11 is obtained by mixing 2.5% by weight of AND with 4,4′-bis (2- {4- (N, N-diphenylamino) phenyl} vinyl) biphenyl (DPAVBi). For example, the film is formed with a film thickness of 30 nm through the mask 16. Next, on each light emitting layer 11, 8-hydroxyquinoline aluminum (Alq 3) is formed as an electron transport layer 12 with a film thickness of, for example, 20 nm through the mask 16 in common for all RGB pixels. Next, lithium fluoride (LiF) is formed as an electron injection layer 13 on the electron transport layer 12 with a film thickness of, for example, 0.3 nm through a mask 16. Then, a cathode made of magnesium silver (MgAg) is formed as the second electrode 8 with a film thickness of 10 nm, for example.

  According to the present embodiment described above, the following effects can be obtained.

  (1) In this embodiment, a plurality of ribs 14 projecting from the surface 5 a of the insulating film 5 in the thickness direction Y of the organic EL display device 1 are provided on the insulating film 5, and each of the plurality of organic EL elements 4 is provided. Is formed between these ribs 14. Therefore, when the organic layer 7 is formed on the first electrode 6 using the deposition mask 16 by vapor deposition, the mask can be brought into close contact with the surface 14 a of the rib 14. Contact between the electrode 6 and the mask and the organic layer 7 provided on the surface of the first electrode 6 can be prevented. Therefore, damage due to the mask 16 can be prevented, and as a result, a decrease in the yield of the organic EL display device 1 can be prevented.

  (2) Since each of the plurality of organic EL elements 4 is formed between the ribs 14, when forming each pixel region 2R, 2G, 2B, a light emitting material of a different color is formed in the adjacent pixel region. It becomes possible to prevent mixing. Therefore, it is possible to prevent color mixing between display pixels, and as a result, it is possible to prevent deterioration in image quality.

  (3) Furthermore, since it is not necessary to provide a spacer in the pixel region, it is possible to form the organic layer 7 having a uniform film distribution and a film thickness necessary for efficient light emission. Therefore. Since the occurrence of defective pixels can be prevented, the image quality can be prevented from deteriorating. Further, since it is not necessary to provide a spacer in the pixel region, it is possible to prevent the aperture ratio from being lowered. Accordingly, it is possible to prevent a decrease in luminance and obtain a good image quality.

  (4) In the present embodiment, the insulating film 5 is formed so as to cover the peripheral edge 6 a of the first electrode 6. Therefore, a short circuit between the first electrode 6 and the second electrode 8 due to the shadow phenomenon can be avoided, and the occurrence of leakage current can be prevented. As a result, it is possible to prevent a decrease in light emission efficiency of the element.

  (5) In the present embodiment, the insulating film 5 and the ribs 14 are integrally formed of the same insulating resin material. Therefore, the manufacturing process of the organic EL display device 1 can be simplified.

(6) In the present embodiment, the thickness T _{2 of the} rib 14 is set to 1 μm or more and 50 μm or less. Therefore, even when the ribs 14 are provided, it is possible to cope with the thinning of the organic EL display device 1, and on the surfaces of the mask 16 and the first electrode 6, and the mask 16 and the first electrode 6. It is possible to reliably prevent contact with the organic layer 7 provided on the surface.

(7) In the present embodiment, the thickness T ₁ of the insulating film 5 is set to 0.2 μm or more and 1.0 μm or less. Therefore, it is possible to prevent a decrease in the light emission efficiency of the element due to the generation of a leakage current without causing interference such as color mixing between adjacent pixel regions 2R, 2G, and 2B.

  (8) In the present embodiment, each organic EL element 4 may be formed between the ribs 14, and it is not necessary to surround the entire periphery of the organic EL element 4 with the ribs 14. Liquid draining can be performed.

  In addition, you may change the said embodiment as follows.

  In the above embodiment, the ribs 14 having a substantially rectangular cross section are provided. However, the shape of the ribs 14 is not particularly limited, as long as the mask 16 can be in close contact with the surface 14a of the ribs 14. Any shape is acceptable. For example, as shown in FIG. 11, it is good also as a structure which provides the rib 14 which has a cross-sectional substantially trapezoid shape. With such a configuration, the adhesion between the surface 14a of the rib 14 and the mask can be improved.

  In the above embodiment, the insulating film 5 and the ribs 14 are integrally formed of the same material, but the insulating film 5 and the ribs 14 may be formed separately from different materials. Moreover, in the said embodiment, although the insulating film 5 and the rib 14 were formed simultaneously, it is good also as a structure which forms the insulating film 5 and the rib 14 by another process. For example, first, the insulating film 5 is formed by performing exposure and development using the above-described photosensitive polyimide resin. Next, the rib 14 may be formed on the surface of the insulating film 5 by applying a photosensitive acrylic resin on the insulating film 5 and performing exposure and development processes.

  -It is good also as a structure which provides a sealing film (not shown) on the 2nd electrode 8. FIG. The sealing film has a role of protecting the second electrode 8 from moisture in the atmosphere, and the sealing film is formed so as to cover the second electrode 8. This sealing film can be formed of, for example, glass or plastic.

  As described above, the present invention is suitable for an organic EL display device including an organic EL panel having an organic EL element and a manufacturing method thereof.

1 is a plan view of an organic EL display device according to an embodiment of the present invention. It is AA sectional drawing of FIG. It is sectional drawing for demonstrating the organic layer which comprises the organic EL element with which the organic EL display apparatus which concerns on embodiment of this invention is provided. It is a top view for demonstrating arrangement | positioning of the insulating film with which the organic electroluminescence display which concerns on embodiment of this invention is provided. It is sectional drawing in order to demonstrate the manufacturing method of the organic electroluminescence display which concerns on embodiment of this invention. It is sectional drawing in order to demonstrate the manufacturing method of the organic electroluminescence display which concerns on embodiment of this invention. It is sectional drawing in order to demonstrate the manufacturing method of the organic electroluminescence display which concerns on embodiment of this invention. It is sectional drawing in order to demonstrate the manufacturing method of the organic electroluminescence display which concerns on embodiment of this invention. It is sectional drawing in order to demonstrate the manufacturing method of the organic electroluminescence display which concerns on embodiment of this invention. It is sectional drawing in order to demonstrate the manufacturing method of the organic electroluminescence display which concerns on embodiment of this invention. It is a top view which shows the modification of the organic electroluminescence display which concerns on embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Organic EL display device 3 Insulating substrate 4 Organic EL element 5 Insulating film 5a Surface of insulating film 6 First electrode 6a Peripheral portion of first electrode 7 Organic layer 8 Second electrode 11 Light emitting layer 14 Rib 14a Rib surface 16 Mask Thickness of T1 insulating film T2 Thickness of rib Y Thickness direction of organic EL display device

Claims (12)

An insulating substrate;
A plurality of organic layers having a first electrode formed on the insulating substrate, an organic layer formed on the first electrode and having a light emitting layer, and a second electrode formed on the organic layer. An EL element;
An organic EL display device comprising: an insulating film formed on the insulating substrate and defining the plurality of organic EL elements;
A plurality of ribs protruding from the surface of the insulating film in the thickness direction of the organic EL display device are provided on the insulating film, and each of the plurality of organic EL elements is formed between the ribs. An organic EL display device comprising:   The organic EL display device according to claim 1, wherein the insulating film is formed so as to cover a peripheral portion of the first electrode.   3. The organic EL display device according to claim 1, wherein the insulating film and the rib are integrally formed of the same material.   The organic EL display device according to claim 1, wherein a thickness of the rib is 1 μm or more and 50 μm or less.   5. The organic EL display device according to claim 2, wherein the insulating film has a thickness of 0.2 μm to 1.0 μm. A method of manufacturing an organic EL display device comprising a plurality of organic EL elements in which a first electrode, an organic layer having a light emitting layer, and a second electrode are formed in this order on an insulating substrate,
Forming a plurality of the first electrodes on the insulating substrate;
Forming an insulating film for partitioning the plurality of first electrodes on the insulating substrate;
Forming a plurality of ribs projecting in the thickness direction of the organic EL display device from the surface of the insulating film on the insulating film, and disposing each of the plurality of first electrodes between the ribs;
Providing a mask on the surface of the rib, and attaching the mask to the rib;
Forming the organic layer on the first electrode using the mask, and forming the second electrode on the organic layer. The method for manufacturing an organic EL display device, comprising:   The method of manufacturing an organic EL display device according to claim 6, wherein the insulating film is formed so as to cover a peripheral portion of the first electrode.   8. The method of manufacturing an organic EL display device according to claim 6, wherein the insulating film and the rib are formed simultaneously.   9. The method of manufacturing an organic EL display device according to claim 8, wherein the insulating film and the rib are integrally formed of the same material.   2. The insulating film and the rib are formed by multiple exposure in which the material is a photosensitive material and the photosensitive material is sequentially exposed with a plurality of exposure masks having different exposure patterns. 9. A method for producing an organic EL display device according to 9.   The thickness of the said rib is formed in 1 micrometer or more and 50 micrometers or less, The manufacturing method of the organic electroluminescence display of any one of Claims 6-10 characterized by the above-mentioned.   The method of manufacturing an organic EL display device according to claim 6, wherein the insulating film is formed to have a thickness of 0.2 μm to 1.0 μm.

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