JP4470241B2 - Organic EL display and manufacturing method thereof - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an organic EL display and a manufacturing method thereof, and more particularly to an organic EL display formed by arranging a plurality of light emitting portions and a manufacturing method thereof.
[0002]
[Prior art]
In recent years, flat panel displays such as liquid crystal displays (LCD) and plasma displays (PDP) have been actively developed. Among these, an organic EL (Electroluminescence) display has been attracting attention as a method capable of self-luminous and high-definition display.
[0003]
The organic EL has an element structure of indium tin oxide (ITO) / organic hole transport layer / organic light emitting layer / cathode as shown in the document “Appl. Phys. Lett. 51, 913 (1987)”. . W. Tang et al. Led to a wider research and development triggered by what was proposed in 1987.
[0004]
FIG. 5 is a cross-sectional process diagram for explaining an example of a method for manufacturing an organic EL display. In order to manufacture an organic EL display, first, a striped anode (transparent electrode) 2 is patterned on a transparent substrate 1 as shown in FIG. Thereafter, stripe-like spacers 3 extending in a direction intersecting the anode 2 are formed on the transparent substrate 1 by lithography. As described in JP-A-8-315981, the spacer 3 is formed in a cross-sectional overhang shape using a photoresist or polyimide. Next, as shown in FIG. 5B, low molecules emitting light in red (R), green (G), and blue (B) by vacuum deposition from above the deposition mask 4 placed on the spacer 3. Organic layers 5R, 5G, 5B (for example, a laminated film of an organic hole transport layer and an organic light emitting layer) 5R, 5G, 5B are formed separately, and organic layers 5R, 5G, 5B crossing the transparent electrode 2 are sequentially formed between the spacers 3. To do. Thereafter, as shown in FIG. 5C, the cathode material 6 is vapor-deposited using the spacer 3 as a partition, and the cathode 6a is independently formed on each organic EL layer 5R, 5G, 5B. Although not shown here, an organic EL display is completed by providing an insulating protective film for preventing deterioration of the organic layers 5R, 5G, and 5B on the cathode 6a.
[0005]
In the organic EL display obtained by such a method, each cathode 6a is insulated by the spacer 3, and a predetermined voltage is independently applied to each cathode 6a. A current flows through the organic layers 5R, 5G, and 5B located in the region 5 to emit light, and a full color display can be performed.
[0006]
[Problems to be solved by the invention]
However, a general organic EL display has a problem that the organic layer is easily deteriorated due to the influence of organic substances. Therefore, as in the organic EL display obtained as described above, when the spacer 3 made of photoresist or polyimide is left in the display, the organic layers 5R, 5G, and 5B are deteriorated from the spacer 3. The organic matter is released, and due to the influence of the organic matter, problems such as a decrease in light emission efficiency and a reduction in lifetime in the organic layers 5R, 5G, and 5B, and a non-light emitting area (so-called dark spot) are easily generated in the light emitting portion. .
[0007]
Accordingly, an object of the present invention is to provide an organic EL display capable of obtaining a long-life and high-quality image and a manufacturing method thereof.
[0008]
[Means for Solving the Problems]
  In order to achieve such an object, the organic EL display of the present invention is arranged in parallel on a substrate in stripes.pluralFirst electrode, thisA plurality of organic layers each having an organic light emitting layer provided on a position corresponding to the plurality of light emitting portions on the first electrode, a black matrix made of an inorganic insulating material covering a portion other than the light emitting portion of the first electrode, A plurality of ribs that are provided on the black matrix and extend in a direction intersecting with the plurality of first electrodes, and a plurality of second electrodes that are provided on each light emitting portion of the first electrode via an organic layer. ,The rib is made of an inorganic material.
[0009]
  In the organic EL display having such a configuration, the rib standing on the side of the light emitting portion is made of an inorganic material, so that no organic matter is released from the rib, and deterioration of the organic layer due to the organic matter is prevented. .Further, by providing a black matrix made of an inorganic insulating material so as to cover a portion other than the light emitting portion, a luminescence waveguide component along the substrate can be suppressed, and an external light reflection component can also be suppressed. Therefore, a high-definition display with high contrast and no crosstalk can be obtained.
[0010]
  Moreover, the manufacturing method of the organic electroluminescent display of this invention is on a board | substrate.pluralPatterning the first electrode in stripes;A black matrix made of an inorganic insulating material is formed so as to cover a portion of the first electrode other than the plurality of light emitting portions, and then extends on the black matrix in a direction intersecting with the plurality of first electrodes. A plurality of ribs made of an inorganic material are erected. after that,By film formation from above the ribFirst1 electrodeMultiple ofAn organic layer having an organic light emitting layer on the light emitting portionRespectivelyThe first electrode is then formed by film formation on the ribMultiple ofThe second electrode is placed on the light emitting part through the organic layer.RespectivelyIt is characterized by forming.
[0011]
  In such a manufacturing method, since the rib serving as a mask when the organic layer and the second electrode are formed is formed of an inorganic material, the organic material is not released from the rib left on the substrate. An organic EL display capable of preventing deterioration of the organic layer is obtained.Moreover, by forming a black matrix made of an inorganic insulating material so as to cover a portion other than the light emitting portion, the luminescence waveguide component along the substrate can be suppressed, and the external light reflection component can also be suppressed. Therefore, a high-definition display with high contrast and no crosstalk can be obtained.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of an organic EL display and a method for manufacturing the same according to the present invention will be described in detail with reference to the drawings. FIG. 1 is a cross-sectional view showing an example of the organic EL display of the present invention, FIG. 2 is a plan view of the organic EL display with the main part cut away, and FIG. 3 is the organic EL shown in FIGS. It is sectional process drawing for demonstrating the manufacturing method of a display. 1 and 3 correspond to the A-A ′ cross section of FIG. 2.
[0013]
In this embodiment, a simple matrix type full-color display is taken as an example of the organic EL display, and the configuration will be described in the order of the manufacturing process.
[0014]
First, as shown in FIG. 3A, a transparent substrate 11 made of a translucent material is prepared. The material, thickness, size, and the like of the substrate 11 are not particularly limited, and for example, glass, an organic polymer material such as a translucent polyester film, or the like can be used.
[0015]
Next, the transparent conductive material layer 12 constituting the first electrode is formed on the substrate 11. The transparent conductive material layer 12 is preferably highly conductive, for example, indium tin oxide (ITO) or tin oxide (SnO).₂), Zinc oxide (ZnO), or the like is used. Here, ITO is used as an example. The method for forming the transparent conductive material layer 11 is not particularly limited, but can be formed by a DC sputtering method, an RF magnetron sputtering method, a CVD method, a reactive vacuum deposition method, or the like.
[0016]
Next, the transparent conductive material layer 12 is patterned into a stripe shape, that is, a pattern shape for data lines of a matrix type display, and a transparent electrode 12a made of the transparent conductive material layer 12 is formed as a first electrode. Usually, in the case of a line sequential scanning type flat display, the transparent electrode 12a having a high electrical resistance is not used on the scanning line side through which a large current flows, and the transparent electrode 12a is formed as a vertical data line, Used as an anode for an organic layer to be formed later.
[0017]
The patterning method of the transparent conductive material layer 12 is not particularly limited, but a patterning method in which the edge of the transparent electrode 12a is formed into a tapered shape is desirable. As an example of such a patterning method, hydrochloric acid (HCl) and nitric acid (HNO) using a resist pattern as a mask._ThreeAnd wet etching using a mixed acid.
[0018]
Next, as shown in FIG. 3B, an inorganic insulating film 13 is formed so as to cover the transparent electrode 12a. As this inorganic insulating film 13, a silicon oxide film (SiO₂Or SiOx), silicon nitride film (Si_ThreeN_FourAlternatively, SiNx), silicon oxynitride film (SiOx Ny), or the like is used.
[0019]
The method for forming the inorganic insulating film 13 is not particularly limited, and the inorganic insulating film 13 is formed by a wet method such as a plasma CVD method, a spin coating method, or a sol-gel method.
[0020]
Among these, when the plasma CVD method is adopted, the source gas is not particularly limited, but the film formation is performed by the TEOS plasma CVD method in which a liquid source such as TEOS (Tetraethoxy silane) is vaporized to form a film. Can do. In particular, when the underlying transparent electrode 12a is made of ITO, if the transparent electrode 12a is exposed to plasma for a long time during the formation of the inorganic insulating film 13, the threshold voltage of the obtained organic EL element tends to increase. This must be noted because there are. For this reason, the film formation by the TEOS plasma CVD method is advantageous in that the damage to the base is small.
[0021]
  As the inorganic insulating film 13, aluminum oxide (Alx Oy) or an oxide of an aluminum alloy can be used. In this case, the inorganic insulating film 13 is formed by forming an aluminum film and anodizing it in a solution such as oxalic acid to form an aluminum oxide film, which is used as the inorganic insulating film 13. The method can be adopted. At this time, the porous inorganic insulating film 13 can be obtained depending on the electrolysis conditions. Then, by changing the diameter of the hole, the inorganic insulating film 13 can be made a good absorber for light in the visible region. Also thisEtBy carrying out the sealing treatment, it is possible to obtain a color anodized in various colors.
[0022]
  In particular, by using black alumite, the inorganic insulating film 13 obtained from the substrate can suppress the luminescence waveguide component along the substrate 11, and can also suppress the external light reflection component. In addition, a high-definition display without crosstalk can be obtained. That is, like thisblackIf the inorganic insulating film 13 made of alumite is used, the inorganic insulating film 13 also has a black matrix function. When the inorganic insulating film 13 made of an oxide of an aluminum alloy is formed by anodizing a silicon-containing aluminum alloy, a sufficiently blackened alumite film can be obtained even without performing a sealing treatment. be able to.
[0023]
After the inorganic insulating film 13 is formed as described above, the portion of the inorganic insulating film 13 on the transparent electrode 12a corresponding to the light emitting portion of each pixel is etched by etching using a resist pattern formed by lithography as a mask. By removing, an opening 13 a is formed in the inorganic insulating film 13. Therefore, the light emitting portion 12b of the transparent electrode 12a is exposed for each pixel.
[0024]
At this time, when the inorganic insulating film 13 is made of silicon oxide, silicon nitride, or the like, tetrafluoromethane (CF_Four) Etc., by employing plasma etching such as RIE (Reactive Ion Etching) using a fluorine-based etching gas, it is inorganic with a sufficient selectivity with respect to the underlying transparent electrode 12a made of ITO. The insulating film 13 can be etched, and the opening 13a is formed in the inorganic insulating film 13 with little etching of the transparent electrode 12a.
[0025]
However, in order to suppress the disconnection of the cathode formed on the inorganic insulating film 13 in the subsequent steps, in order to taper the side wall of the inorganic insulating film 13, some oxygen (O₂). Therefore, the etching rate of the resist pattern is increased, the inorganic insulating film 13 is etched while forming the side wall protective film, and the etching side wall (that is, the side wall of the inorganic insulating film 13) is tapered.
[0026]
The etching of the inorganic insulating film 13 made of silicon oxide or silicon nitride is not limited to the dry etching such as RIE described above, and wet etching using a hydrofluoric acid-based etching solution may be employed.
[0027]
When the inorganic insulating film 13 is made of an oxide of aluminum oxide or aluminum alloy, it is preferable to pattern the aluminum oxide or aluminum alloy before performing anodic oxidation for forming the inorganic insulating film 13. . This is because, in the etching of the oxide constituting the inorganic insulating film 13, wet etching with high-temperature phosphoric acid is performed. However, when this oxide is patterned, there is no resist pattern serving as a mask and oxidation is performed. This is because the patterning of objects becomes difficult.
[0028]
Next, as shown in FIG. 3C, the lower layer 14 and the upper layer are formed in a stripe shape orthogonal to the transparent electrode 12a on the inorganic insulating film 13 on the side of the opening 13a (that is, on the side of the light emitting portion 12b of the transparent electrode 12a). 15 is formed. The rib 16 has a height of about 0.5 μm to 10 μm, is made of an inorganic material, has a lower layer 14 undercut with respect to the upper layer 15, and has a cross-sectional overhang shape in which the upper layer 15 protrudes in the direction of the opening 13 a. To be molded.
The formation procedure of the rib 16 will be described in detail with reference to FIG. 4 after the manufacturing method of the organic EL display is described with reference to FIG.
[0029]
Next, as shown in FIG. 3D, a mask (not shown) is disposed on the substrate 11 using the ribs 16 as spacers, and the organic layers 17R and 17G are formed in the openings 13a by film formation from the mask. , 17B. Here, the organic light emitting layer 17R that emits red (R), the organic light emitting layer 17G that emits green (G), and the organic that emits blue (B) are emitted by sequentially repeating mask movement, exchange, and film formation. The light emitting layer 17B is pattern-formed along the transparent electrode 12a. At this time, film formation is performed so that the light emitting portion 12b of the transparent electrode 12a is completely covered with the organic light emitting layers 17R, 17G, and 17B.
[0030]
The organic layers 17R, 17G, and 17B for each color are formed of a laminated film such as an organic hole transport layer (not shown) and an organic light emitting layer (not shown) on the upper surface. Further, the order of formation and arrangement of the organic layers 17R, 17G, and 17B for each color, the type of material, the configuration, the film thickness, the dye doping mode, and the like are not particularly limited. For example, as the organic layer 17G that emits green light, an Alq on an organic hole transport layer made of TPD, α-NPD, or the like is used._ThreeA two-layer structure in which an organic light emitting layer that also serves as an electron transporting layer is laminated is used. Depending on the emission color, the organic light emitting layer is composed of Alq doped with an appropriate dye. Since these materials are low molecular organic materials, they can be formed by a vacuum deposition method.
[0031]
Depending on the film configuration, only the organic light emitting layer doped with each dye may be patterned using a mask, and other films may be formed in a lump without using a mask. Further, the emission color is not limited to the three RGB colors, and may be a combination of other emission colors.
[0032]
After the above, as shown in FIG. 1, the conductive material 18 is collectively formed using the ribs 16 as a mask, whereby the cathode 18 a made of the conductive material 18 is formed on the substrate 11 between the ribs 16. It is formed as an electrode. Since the cathode 18a is formed using the rib 16 as a mask, it is formed in a stripe shape intersecting the transparent electrode 12a on the opening 13a and used as a scanning line of the organic EL display.
[0033]
In addition, here, the height of the surface of the cathode 18a is suppressed to be lower than the surface height of the lower layer 14 of the rib 16. As a result, it is possible to prevent the cathode 18a from being short-circuited by the conductive material 18 adhering to the side wall of the upper layer 15 of the rib 16 during film formation for forming the cathode 18a, and the cathode 18a can be formed in an electrically insulated stripe shape. 18a can be formed.
[0034]
The material constituting the cathode 15 is aluminum, but is not limited thereto. For example, a material obtained by doping aluminum (Li) with an appropriate method or a magnesium (Mg) -silver (Ag) alloy. An alloy containing a metal of group 2A of the periodic table such as may be used. All of these materials have a low work function, and have an effect of lowering the threshold voltage of light emission in the organic light emitting layer constituting the organic 17R, 17G, 17B. Moreover, the film-forming method for forming the cathode 15 is not limited, For example, a vacuum evaporation method, a sputtering method, etc. are used.
[0035]
After the above, although illustration is omitted here, an extraction electrode portion for connection with the driver circuit is provided around the pixel portion (region where the display portion 12b is disposed), or the organic light emitting layers 17R and 17G. , 17B protects oxygen and moisture in the air from contact with each other. For example, an insulating protective film for overcoat is formed using a material capable of forming a film with low damage at low temperature, thereby completing an organic EL display. Let
[0036]
Next, an example of a rib forming method will be described using the cross-sectional view of FIG.
[0037]
First, as described with reference to FIGS. 3A and 3B, the transparent electrode 12a is formed on the substrate 11, and the opening 13a is formed in the inorganic insulating film 13 covering the transparent electrode 12a. The process up to the step of exposing the display part 12b of 12a is performed. Thereafter, as shown in FIG. 4A, a lower layer 14 made of chromium (Cr) is formed to a thickness of 1 μm on the inorganic insulating film 13 in which the opening 13a is formed, and further, silicon oxide is formed on the upper surface. The upper layer 15 to be formed is formed to a thickness of 4 μm. Further, a chromium layer 20 serving as an etching mask is formed on the upper layer 15 to a thickness of 0.2 μm.
[0038]
The method for forming these layers is not particularly limited, but the lower layer 14 and the chromium layer 20 are formed by sputtering, vacuum evaporation by EB heating, or the like. The upper layer 15 made of silicon oxide is formed by TEOS plasma CVD or silane (SiH_Four) And oxygen (O₂) Or silane (SiH)_Four) And dinitrogen monoxide (N₂The film is formed by a plasma CVD method using O). However, it is desirable to select a film forming method and film forming conditions for the material constituting the rib so that the higher the height of the rib, the more stress relaxation is performed on the base.
[0039]
Next, as shown in FIG. 4B, a resist pattern 21 is formed on the chromium layer 20 by photolithography. The resist pattern 21 is formed in a stripe pattern intersecting the transparent electrode 12a on the side of the light emitting portion 12b of the transparent electrode 12a, that is, the rib pattern.
[0040]
Next, the chromium layer 20 is etched using the resist pattern 21 as a mask. This etching may be either wet etching or dry etching. However, if the rib pattern requires fine dimensional accuracy, it is preferably performed by RIE with high vertical processing accuracy. At this time, as an etching gas, chlorine gas (Cl₂) And oxygen gas (O₂) Can be used, but other gases may also be used.
[0041]
Thereafter, the upper layer 15 made of silicon oxide is etched using the chromium layer 20 as a mask. At this time, for example, an octafluorocyclobutane gas (C_FourF₈However, the present invention is not limited to this, and dry etching using high-density plasma such as ECR (Electron Cyclotron Resonance) plasma etching or NLD (Neutral Line Discharge) plasma etching may be used. Also, the etching gas is C_FourF₈Without being limited to tetrafluoromethane (CF_Four) And O₂A mixed gas may be used.
[0042]
Next, as shown in FIG. 4 (c), resist pattern components, resist pattern residues, and C that are scattered during the etching of the chromium layer (20) and the upper layer 15 are further removed._FourF₈In order to remove the organic volume generated by the etching gas as described above from the substrate 11, an ashing process using oxygen plasma is performed. This prevents the organic material from remaining on the substrate 11.
Note that when the etching of the chromium layer 20 and the upper layer 15 described with reference to FIG. 4B is performed by wet etching, the ashing process here is not necessarily required.
[0043]
Thereafter, as shown in FIG. 4D, the lower layer 14 is isotropically etched using the upper layer 15 as a mask. At this time, for example, wet etching using a mixed aqueous solution of ceric ammonium nitrate and perchloric acid is performed as an etching solution. Since wet etching is isotropic etching and etching proceeds not only in the depth direction but also in the lateral direction, side etching of the lower layer 14 below the patterned upper layer 15 proceeds and an undercut occurs. . For this reason, the rib 16 composed of the lower layer 14 and the upper layer 15 has a side wall formed in an overhang shape. In this etching, if the chromium layer (20) remains on the upper layer 15, this chromium layer is also removed at the same time.
[0044]
Note that wet etching is inferior in the uniformity of the etching rate within the surface of the substrate 11, and is therefore difficult to apply to rib processing of large area displays. For this reason, in the case of a large area display, after the lower layer 14 is etched to some extent by dry etching with high in-plane uniformity of the etching rate, the side etching of the lower layer 14 may be advanced by performing wet etching. However, when the lower layer 14 is completely removed by dry etching, the transparent electrode 12a is not formed in the opening 13a of the inorganic insulating film 13.Light emitting part12b is exposed to plasma and damaged. Because of thisLight emitting partSince the element characteristics of the organic EL element obtained by forming the organic layer on 12b deteriorate,Light emitting partIt is desirable to terminate dry etching with the lower layer 14 left on 12b and switch to wet etching.
[0045]
As described above, the overhanging rib 16 made of the inorganic material in the present invention is obtained.
[0046]
In the above description, the chromium layer 20 is used as an etching mask for the upper layer 15 made of silicon oxide. However, the pattern etching of the upper layer 15 is not limited to this. For example, when the upper layer 15 can be selectively etched with respect to the resist pattern 21, the resist pattern 21 may be directly used as an etching mask for the upper layer 15 without forming the chromium layer 20.
[0047]
Further, silicon oxide (upper layer 15) and chromium (lower layer 14) were used as materials constituting the ribs 16. However, the rib 16 only needs to have a multilayer structure using an inorganic material whose etching rate is lower as the upper layer. By combining such materials and performing the isotropic etching of the lower layer 14, the overhanging rib 16 is obtained. be able to.
[0048]
For example, as the upper layer 15 constituting the rib 16, in addition to silicon oxide, a silicon oxide or silicon nitride material such as silicon nitride (SiNx) or silicon oxynitride (SiOxNy) may be used. The method for forming the upper layer 15 made of these materials is not particularly limited, and can be formed by a plasma CVD method, a sputtering method, or the like.
[0049]
In addition to chromium, nickel (Ni), titanium (Ti), molybdenum (Mo), or the like may be used as the lower layer 14 for the upper layer 15 made of such a material. The method for forming the lower layer 14 made of these materials is not particularly limited, and can be formed by a vacuum deposition method, a sputtering method, or the like. In the etching of these materials, wet etching using an appropriately selected etching solution and dry etching using an appropriately selected gas are performed.
[0050]
Furthermore, in the embodiment, the height of the lower layer 14 is 1 μm, and the height of the upper layer 15 is 4 μm. However, the height of the rib 16 may be such that the surface height of the lower layer 14 of the rib 16 is higher than the height of the surface of the cathode 18a. With this height, the cathode 18a is electrically insulated without short-circuiting by the conductive material 18 attached to the side wall of the upper layer 15 of the rib 16 during film formation for forming the cathode 18a. It will be formed in stripes. However, in consideration of the manufacturing cost of the display panel and the accuracy of mask vapor deposition when forming the organic layers 17R, 17G, and 17B, it is desirable to suppress the height of the ribs 16 to a certain level. For this reason, the height of the entire rib 16 is preferably set in a range of 0.5 μm to 10 μm.
[0051]
In the organic EL display having the rib 16 formed as described above, since the rib 16 is made of an inorganic material, the organic material is not released from the rib 16 and the organic layers 17R and 17G made of the organic material are used. , 17B can be prevented. As a result, the light emission efficiency in the organic layers 17R, 17G, and 17B is maintained, and it is possible to prevent the occurrence of defects such as non-light emitting areas (so-called dark spots) in the light emitting portion 12b, thereby extending the life of the organic EL display. It becomes possible to plan.
[0052]
Moreover, when the ribs 16 made of this inorganic material are formed in stripes and the side walls thereof are formed in an overhang shape having an undercut, the cathode 18a is formed by film formation from above the ribs 16. The striped cathodes 18a can be formed by self-alignment using the ribs 16 as a mask during film formation, and the ribs 16 can serve as partition walls to keep the cathodes 18a in an insulated state. In particular, it is difficult to produce a vapor deposition mask in order to form a line and space pattern of 100 μm or less (that is, a striped cathode 18a) over a large area by a vacuum vapor deposition method using a vapor deposition mask. However, there is a problem that it is difficult to obtain a good pattern shape due to large pattern distortion caused by mask deformation. Therefore, this problem can be solved by adopting the method of the present embodiment in which the cathode 18a is formed by film formation using the overhanging rib 16 as a mask.
[0053]
In the present embodiment, the configuration and the manufacturing method of a simple matrix type full-color organic EL display have been described as an example. However, the present invention can also be applied to an active matrix display equipped with a thin film transistor (TFT) and a manufacturing method thereof. However, in the active matrix display, since the scanning line can be formed on the base of the organic layers 17R, 17G, and 17B, it is not necessary to use the cathode 18a as the scanning line. In this case, the cathode 18a may be a solid film and need not be insulated by the ribs 16. Therefore, when the scanning lines are formed on the base of the organic layers 17R, 17G, and 17B in the active matrix display, the ribs 16 do not need to be overhanged. In this case, the ribs 16 are formed in the organic layers 17R, 17G, It will be used as a spacer between the substrate 11 and the deposition film forming mask used when forming 17B.
[0054]
【The invention's effect】
As described above, according to the present invention, the rib standing on the side of the light emitting portion is made of an inorganic material, so that organic matter is not released from the rib, and deterioration of the organic layer due to the organic matter is prevented. be able to. As a result, the luminous efficiency of the organic layer is maintained, and it is possible to prevent the occurrence of problems such as the occurrence of non-light-emitting areas (so-called dark spots) in the light-emitting portion, thereby improving the image quality and extending the life of the organic EL display. Is possible. Moreover, the ribs made of the inorganic material are formed in a stripe shape intersecting the first electrode, and the side walls thereof are overhanged, so that the stripe-shaped second electrode is self-aligned by film formation using the rib as a mask. Can be formed. As a result, it is possible to form a fine stripe-shaped second electrode without using a vapor deposition mask.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view of an organic EL display according to an embodiment.
FIG. 2 is a plan view of an essential part of the organic EL display according to the embodiment.
FIG. 3 is a cross-sectional process diagram for explaining the method of manufacturing the organic EL display according to the embodiment.
FIG. 4 is a cross-sectional process diagram for explaining the manufacture of ribs in the organic EL display of the embodiment.
FIG. 5 is a cross-sectional process diagram for explaining a conventional organic EL display and a manufacturing method thereof.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 11 ... Board | substrate, 12a ... Transparent electrode (1st electrode), 12b ... Light-emitting part, 14 ... Lower layer, 15 ... Upper layer, 16 ... Rib, 17R, 17G, 17B ... Organic layer, 18a ... Cathode (2nd electrode)

Claims (13)

A plurality of first electrodes arranged in parallel in a stripe pattern on the substrate;
A plurality of organic layers provided on the first electrode at positions corresponding to the plurality of light emitting portions, each having an organic light emitting layer;
A black matrix made of an inorganic insulating material covering a portion other than the light emitting portion of the first electrode;
A plurality of ribs standing on the black matrix and extending in a direction intersecting with the plurality of first electrodes;
A plurality of second electrodes provided on each light emitting portion of the first electrode via the organic layer;
Prepared,
The rib is made of an inorganic material. The organic EL display according to claim 1,
2. The organic EL display according to claim 1, wherein the rib is provided in a stripe shape so as to intersect the first electrode. The organic EL display according to claim 2.
2. The organic EL display according to claim 1 , wherein the rib is formed in an overhang shape on a side wall facing the first electrode . The organic EL display according to claim 3.
2. The organic EL display according to claim 1, wherein the rib has a multilayer structure made of a material having a slower etching rate as the upper layer. The organic EL display according to claim 4, wherein
The organic EL display, wherein the rib has a multilayer structure including at least two layers of an upper layer made of a silicon oxide-based material or a silicon nitride-based material and a lower layer made of chromium, nickel, titanium, or molybdenum. Forming a plurality of first electrodes in a stripe pattern on a substrate;
Forming a black matrix made of an inorganic insulating material so as to cover a portion of the first electrode other than the plurality of light emitting portions;
Providing a plurality of ribs made of an inorganic material on the black matrix so as to extend in a direction intersecting the plurality of first electrodes ;
Forming each organic layer having an organic light emitting layer on a plurality of light emitting portions of the first electrode by film formation from the ribs;
By deposition from the said ribs, a plurality of manufacturing process of an organic EL display which is characterized in that the step of forming a second electrode over the organic layer on the light-emitting portion each of said first electrode . In the manufacturing method of the organic electroluminescent display of Claim 6,
In the step of forming the organic layer, film formation is performed in a state where a mask is disposed on the substrate via the rib. A method for manufacturing an organic EL display, comprising: In the manufacturing method of the organic electroluminescent display of Claim 6,
The method of manufacturing an organic EL display, wherein the rib is patterned in a stripe shape so as to intersect the first electrode. 9. The method of manufacturing an organic EL display according to claim 8, wherein a side wall of the rib toward the first electrode is formed in an overhang shape. The organic EL display according to claim 9,
In the step of forming the rib, a multilayer film made of a material having a slower etching rate as the upper layer is subjected to pattern etching. The organic EL display according to claim 10.
In the step of forming the rib, a multilayer film including at least two layers of an upper layer made of a silicon oxide-based material or a silicon nitride-based material and a lower layer made of chromium, nickel, titanium, or molybdenum was formed, and the upper layer was patterned Then, the lower layer is isotropically etched using this as a mask. An organic EL display manufacturing method. A plurality of first electrodes patterned for each pixel on a substrate;
A plurality of organic layers provided on the first electrode at positions corresponding to the plurality of light emitting portions, each having an organic light emitting layer;
A black matrix made of an inorganic insulating material covering a portion other than the light emitting portion of the first electrode;
A plurality of ribs erected on the black matrix;
A second electrode provided on the organic layer;
Prepared,
The rib is made of an inorganic material. Patterning a plurality of first electrodes for each pixel on a substrate;
Forming a black matrix made of an inorganic insulating material so as to cover a portion of the first electrode other than the plurality of light emitting portions;
Erecting a plurality of ribs made of an inorganic material on the black matrix;
A step of placing the mask to form an organic layer having an organic light-emitting layer into a plurality of light emitting portions on one of the first electrode through the mask each said rib as a spacer,
Forming a second electrode on each of the organic layers. A method for manufacturing an organic EL display, comprising:

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