JP2005174842A - Organic el display and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an organic EL display wherein an organic thin film layer has constant thickness and display nonuniformity is reduced, and to provide its manufacturing method. <P>SOLUTION: This organic EL display is provided with a positive electrode wiring 1 formed on a substrate, a plurality of partitions 10 formed to intersect the positive electrode wiring 1, a partition junction part 24 provided between the adjacent partitions 10 and connected with the adjacent partition 10, an organic compound layer formed by applying a fluid material on the anode wiring 1 and a negative electrode wiring 5 divided by the partitions. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an organic EL (ElectroLuminescence) display device and a method for manufacturing an organic EL display device.

  In recent years, organic EL displays using organic EL elements have been actively developed. The organic EL display is expected as a next-generation display device because it has a wider viewing angle than liquid crystal display devices, has a high response speed, and has a variety of light emission properties of organic substances. An organic EL device has an anode formed on a substrate, a thin organic compound layered on the anode, and a cathode formed on the organic compound layer so as to face the anode formed on the substrate. It is a structured. An organic EL element is a current-driven display element that emits light when a current is supplied to an organic compound layer disposed between an anode and a cathode. Hereinafter, a thin film of an organic compound to be laminated is referred to as an organic thin film layer. A display pixel is a portion where an anode, a plurality of organic thin film layers, and a cathode are stacked.

  When an organic compound is stacked on an electrode provided on a substrate, an organic thin film layer may be formed by vacuum evaporation of an organic material. However, when an organic material is deposited, if the surface of the electrode serving as the base of the organic thin film layer has foreign matters attached, protrusions, or depressions, the organic thin film layer may not be in a desired state due to the influence.

  As a method for solving this problem, a technique for forming a desired organic thin film layer by dispersing or dissolving an organic material to be an organic thin film layer in a liquid and coating it as a solution to cover foreign matters, protrusions, depressions, etc. A wet coating method, hereinafter simply referred to as a coating method) is known. For example, Patent Document 1 describes that at least one of the organic thin film layers is formed by a coating method.

  Examples of the coating method include an offset printing method, a relief printing method, and a mask spray method. In the offset printing method and the relief printing method, a layer of a solution in which an organic material is dispersed or dissolved in a solvent is formed only in a predetermined region. In the mask spray method, a metal mask or the like having an opening that matches a desired region is disposed, and a solution in which an organic material is dispersed or dissolved is sprayed. In this case, the solution is dispersed in a gaseous medium such as nitrogen, or the solution is atomized using a two-fluid nozzle or the like.

  In the organic EL display, the cathode wiring provided on the organic thin film layer is separately arranged. For this purpose, a separation structure (hereinafter referred to as a partition) is provided (see Patent Document 1). FIG. 8 is a cross-sectional view showing an example of a partition wall described in Patent Document 1. As shown in FIG. An anode wiring 101 is provided on the substrate 111, and then a partition wall 100 is provided. For example, the partition wall 100 is formed so that the cross section increases as the distance from the substrate 11 increases. Such a structure of the partition wall 100 is called an inverted taper structure or an overhang structure. By making the partition wall 100 have an inversely tapered structure, the cathode wiring can be more reliably separated. When each organic thin film layer (hole injection transport layer 102, light emitting layer 103, electron injection transport layer 104) is formed by a coating method or the like with the partition wall 100 provided, the organic thin film layer is separated by the partition wall 100. Each organic thin film layer is formed between the partition walls 100. Thereafter, the cathode wiring 105 is formed by a vapor deposition method or the like. The cathode wiring 105 is separated by the partition wall 100 to form a patterned cathode wiring 105.

  In some cases, an insulating film having an opening is formed over the anode wiring, and a position to be a display pixel is determined by the position of the opening. FIG. 9 is an explanatory diagram showing a configuration example in the case where an insulating film having an opening is provided in the configuration described in Patent Document 1. In FIG. Fig.9 (a) is a schematic diagram which shows the condition which observed the board | substrate from the side by which an electrode is arrange | positioned, FIG.9 (b) is sectional drawing in AA 'of Fig.9 (a). FIG. 9A also shows components that are hidden by cathode wiring or the like provided in the upper layer.

  In the example shown in FIG. 9, first, the anode wiring 101 and the cathode connection wiring 121 connected to the cathode wiring are formed on the substrate 111. Subsequently, an insulating film 122 having an opening 123 is formed. The opening 123 is provided at a position where the anode wiring and the cathode wiring cross each other. A partition wall 100 is formed so as to be orthogonal to the anode wiring 101. Subsequently, an organic material solution is applied or evaporated to form the organic thin film layer 124. Although a plurality of layers are formed as the organic thin film layer, in FIG. 9B, the plurality of layers are collectively shown as the organic thin film layer 124. The solution adjusts the organic material concentration and the like so that the organic thin film layer is formed with a constant thickness in the region where the organic thin film layer is to be formed. After the organic thin film layer 124 is formed, the cathode wiring 105 is deposited on the organic thin film layer. The partition wall 100 separates the organic thin film layer 124 and the cathode wiring 105 to form the organic thin film layer 124 between the partition walls, and the patterned cathode wiring 105 is formed.

  After forming the cathode wiring 105, an organic thin film layer made of a polymer or the like may be formed on the cathode wiring 105 in order to protect the organic EL element. This organic thin film layer (not shown) is also formed by a coating method or the like.

  Further, another substrate (not shown) is disposed so as to face the surface of the substrate 111 on which the electrodes and the like are disposed. In this substrate, a sealing material (not shown) is applied to the outer periphery of the region of the substrate 111 facing the organic EL element. With this sealing material, the substrate 111 and another substrate are bonded. The organic EL element is kept from being exposed to moisture and oxygen by being sealed with a substrate and a sealing material.

  However, when an organic material solution is applied after the partition wall 100 is formed, there arises a problem that the applied solution spreads along the partition wall 100. For example, in the example illustrated in FIG. 9, the solution spreads along a portion where the side surface of the partition wall 100 and the insulating film 122 intersect. This is because a phenomenon similar to the capillary action is caused by the space near the portion where the side surface of the partition wall 100 and the surface of the insulating film 122 intersect. In particular, when the partition wall 100 is formed so as to have an inverted taper structure in order to reliably separate the cathode wiring 105 and the like, the space near the intersection of the side surface of the partition wall 100 and the surface of the insulating film 122 becomes narrower, and the solution is more concentrated. It becomes easy to spread.

  FIG. 10 is an explanatory diagram showing a state in which the organic material solution has spread along the partition walls. In FIG. 10, the partition wall 100 and the organic material solution 125 are shown, and other components are not shown. 9 and 10, a region indicated by a broken line indicates a range where the applied solution should remain without spreading. That is, the solution should ideally not expand beyond this dashed area. However, as already described, the solution 125 spreads along the partition wall 100. As a result, as shown in FIG. 10, the solution spreads beyond the range indicated by the broken line. Also in each figure shown below, the range where the solution should stay is shown with a broken line.

  The concentration of the solution is adjusted so that a constant thickness can be obtained. However, since the solution spreads along the partition wall 100, it is difficult to achieve a desired thickness. In particular, since the solution in the vicinity of the outer peripheral portion of the region indicated by the broken line spreads further outward, the thickness of the organic thin film layer becomes thinner toward the outer peripheral portion of the region indicated by the broken line. As described above, unevenness occurs in the thickness of the organic thin film layer, and thus uneven light emission occurs when each display pixel emits light.

Japanese Patent Laid-Open No. 2001-351799 (paragraphs 0012-0017, FIGS. 1 and 2)

  As described above, the conventional organic EL display device has a problem in that the liquid material serving as the organic layer spreads, uneven emission occurs, and display quality deteriorates.

  The present invention has been made in view of the above-described problems, and an object of the present invention is to provide an organic EL display device excellent in display characteristics and a manufacturing method thereof that prevents the organic layer from spreading.

  An organic EL display device according to the present invention includes a first electrode formed on a substrate (for example, the anode wiring 1 in this embodiment) and a plurality of partition walls formed to intersect the first electrode (for example, The partition wall 10) in this embodiment, a partition wall connection portion (for example, the partition wall connection portion 24 in this embodiment) provided between the adjacent partition walls and connected to the adjacent partition wall, and the first electrode An organic compound layer formed by applying a liquid material on the surface, and a second electrode (for example, the cathode wiring 5 in this embodiment) divided on the organic compound layer by the partition wall. is there. Thereby, display characteristics can be improved.

  In the organic EL display device according to the present invention, in the above-described organic EL display device, a connection wiring that is formed under the partition connection portion so as to intersect the partition connection portion and is electrically connected to the second electrode is provided. In addition, an end of the second electrode is formed inside the partition connection portion. As a result, the second electrode can be connected to the connection wiring without being short-circuited.

  In the organic EL display device described above, it is desirable that a plurality of the partition connection portions are provided, and the plurality of partition connection portions are arranged in a substantially line. Thereby, the uniformity of the organic compound layer can be improved, and the occurrence of display unevenness can be reduced.

  In the organic EL display device described above, it is desirable that the partition and the partition connection portion are formed of substantially the same material. Thereby, the display characteristics of the organic EL display device can be improved by a simple process.

  In a preferred embodiment of the organic EL display device described above, the partition connection portion is formed outside the display area.

  The organic EL display device manufacturing method according to the present invention includes a step of forming a first electrode on a substrate, a step of forming a plurality of partition walls intersecting the first electrode on the first electrode, and A partition connecting portion connected to the adjacent partition, a step of forming an organic compound layer by applying a liquid material on the first electrode, and a partition separated by the partition. Forming two electrodes on the organic compound layer. As a result, an organic EL display device having excellent display characteristics can be manufactured.

  In a preferred embodiment of the organic EL display device described above, the partition and the partition connection portion are formed substantially simultaneously. Thereby, an organic EL display device having excellent display characteristics can be manufactured by a simple process.

  The manufacturing method of the organic EL display device according to the present invention is the above-described manufacturing method of the organic EL display device, wherein the connection wiring crossing the partition connection portion and electrically connected to the second electrode is connected to the partition connection portion. The step of forming the second electrode includes forming the second electrode inside the partition wall connecting portion. As a result, the second electrode can be connected to the connection wiring without being short-circuited.

  The organic EL display device manufacturing method according to the present invention is the above-described organic EL display device manufacturing method, wherein a plurality of the partition connection portions are provided corresponding to the plurality of second electrodes, and the plurality of partition connection portions are substantially omitted. They are arranged in a line. Thereby, the outflow amount of the organic compound layer between the partition walls can be made uniform, and the display characteristics can be made uniform.

  According to the present invention, it is possible to provide an organic EL display device having an excellent display characteristic, and a method for manufacturing the same, by preventing the organic layer from spreading.

  Hereinafter, embodiments to which the present invention can be applied will be described. The present invention is not limited to the following embodiments. For clarity of explanation, the following description is omitted and simplified as appropriate. Further, those skilled in the art will be able to easily change, add, and convert each element of the following embodiments within the scope of the present invention. In addition, what attached | subjected the same code | symbol in each figure has shown the same element, and abbreviate | omits description suitably.

  An element substrate on which an organic EL light emitting element of the organic EL display device according to this example is formed will be described with reference to FIG. FIG. 1 is a plan view showing a configuration of an element substrate of an organic EL display device. Reference numeral 1 is an anode wiring, 5 is a cathode wiring, 10 is a partition, 11 is a substrate, 21 is a + connection wiring, 22 is an insulating film, 23 is an opening, 24 is a partition connection, and 25 is a contact hole.

  A plurality of anode wirings 1 and connection wirings 21 connected to the cathodes are formed on the substrate 11 so as to be in contact with the surface of the substrate 11. The plurality of anode wirings 1 are formed in parallel. The connection wirings 21 are formed corresponding to the number of the cathode wirings 5 and are formed perpendicular to the respective anode wirings 1. The anode wiring 1 and the connection wiring 21 are formed by a transparent conductive film such as ITO. An insulating film 22 is formed on the substrate on which the anode wiring 1 and the connection wiring 21 are formed. The film thickness of the insulating film 22 is 0.7 μm, for example. The insulating film 22 is provided with an opening 23 at a position where the anode wiring 1 and the cathode wiring 5 intersect (that is, a position serving as a display pixel).

  A plurality of organic thin film layers (organic compound layers) and the cathode wiring 5 are sequentially stacked on the insulating film 22. Accordingly, the organic thin film layer is sandwiched between the cathode wiring 5 and the anode wiring 1. However, illustration of the organic thin film layer is omitted in FIG. Further, before the organic thin film layer is formed, a separation structure (hereinafter referred to as a partition wall 10) for separating adjacent cathode wirings is provided. The barrier ribs 10 are separated into a desired pattern at the same time that the cathode wiring 5 is formed by vapor deposition or the like. For example, as shown in FIG. 1, in order to form a plurality of cathode wirings 5 orthogonal to the anode wiring 1, a plurality of partition walls 10 orthogonal to the anode wiring 1 are formed on the anode wiring. The partition wall 10 preferably has an inverted taper structure. That is, it is preferable to form the cross section so as to be separated from the substrate 11. Thereby, the side wall and the rising portion of the partition wall 10 are shadowed by vapor deposition, and the cathode wiring 5 can be divided. The partition wall 10 can be formed with a height of 3.4 μm and a width of 10 μm, for example.

  In this invention, the partition connection part 24 connected to adjacent partition walls is formed. That is, the partition 10 is connected to the adjacent partition 10 provided in parallel by the partition connection portion 24. The partition wall connecting portion 24 is formed perpendicular to the partition wall 10. For example, the partition connection portion 24 is formed outside the display area where the display pixels are formed. That is, the partition wall connection portion 24 is formed in a region outside the extreme end anode wiring 1. The partition wall connecting portion 24 extends from the partition wall 10 to the adjacent partition wall 10. Therefore, the adjacent partition 10 is connected via the partition connection part 24.

  The partition connection portion 24 can be provided in the same manner as the partition 10 in the step of providing the partition 10. That is, exposure is performed using a mask having a pattern corresponding to the partition wall 10 and the partition wall connection portion 24 when patterning the partition wall. The barrier rib 10 and the barrier rib connecting portion 24 are patterned so as to surround one cathode wiring 5 with a U-shaped structure indicated by a one-dot chain line in FIG. Thereby, the partition connection part 24 can be formed by a simple process. The height of the partition connection portion 24 can be formed to be 3.4 μm, which is the same as that of the partition 10. Moreover, it is desirable that the width of the partition connection portion 24 be wider than the partition, for example, 10 to 30 μm.

  When the organic thin film layer is laminated by applying an organic material solution, the organic thin film layer is separated by the partition walls 10. Even if the liquid material that becomes the organic thin film layer flows out of the display area along the partition wall 10, it is blocked by the partition wall connection portion 24. Accordingly, it is possible to prevent the film thickness from being reduced due to the outflow of the organic material, and to make the film thickness of the organic thin film layer in the display pixel constant. Therefore, occurrence of display unevenness can be prevented. Then, the organic material is concentrated and dried to form an organic thin film layer. Thereby, an organic thin film layer having a uniform thickness is formed in the display region.

  Furthermore, in this embodiment, the partition connection portions 24 for the respective cathode wirings 5 are arranged in a line. Therefore, the distance from the end of the display area to the partition wall connection portion 24 is the same in all the cathode wirings. Thereby, the outflow amount of the organic material between the respective partition walls can be made substantially the same, and the occurrence of display unevenness can be reduced.

  After forming the barrier rib 10 and the barrier rib connecting portion 24, a metal material or the like to be the cathode wiring 5 is vapor deposited from above the organic thin film layer. A plurality of cathode wirings 5 can be formed by separating the cathode pattern by the partition wall 10 having a reverse taper structure. In the present embodiment, the deposition end of the cathode wiring 5 is set to the inside of the partition wall connection portion 24 by performing deposition using a deposition mask covering the partition wall connection portion 24 and the outside thereof. The inner side indicates the center side of the display area. The cathode wiring 5 separated by the partition 10 is formed perpendicular to the anode wiring 1. Thereby, an organic thin film layer is disposed between the cathode wiring 5 and the anode wiring 1 at a position where the cathode wiring 5 and the anode wiring 1 intersect.

  When the organic material is applied after the partition wall 10 and the partition wall connecting portion 24 are provided, the organic material spreads along the partition wall 10. Since the space near the portion where the side surface of the partition wall 10 intersects with the insulating film is narrow, the solution is more easily spread in this space. Accordingly, the organic material flows from the vapor deposition source to the shaded portion in the inverted taper structure. When the organic material is concentrated and dried, the concentrated organic material adheres to the portion into which the organic material flows. Therefore, the portion where the height of the partition wall connection portion 24 from the substrate is low becomes large, and the side wall is at an angle close to perpendicular to the substrate. In other words, the reverse taper angle approaches vertical and the reverse taper structure preferable for the separation of the cathode wiring 5 is lost. If the cathode material is vapor deposited from above, the cathode material is vapor deposited not only on the upper surface but also on the side surface of the partition wall, so that the adjacent cathode wiring 5 may not be separated. Therefore, there is a possibility that adjacent cathode wirings 5 are short-circuited.

  The short circuit of the cathode wiring 5 as described above is highly likely to occur at a location where the partition wall 10 and the partition wall connection portion 24 are connected. This is because the partition wall 10 and the partition wall connecting portion 24 are connected at a substantially right angle. That is, the structure made of a photosensitive resin is patterned in a bent configuration. Usually, the cathode material is not completely deposited from the vertical direction but also from the oblique direction. Due to the presence of the partition wall connection portion 24, the vapor deposition material of the cathode wiring 5 is easily attached to the vicinity of the region where the side surface of the partition wall 10 and the side surface of the partition wall connection portion 24 intersect. Further, the cathode wiring 5 is deposited on the upper surface of the partition wall 10. Therefore, the side surface and the upper surface of the structure are covered with the metal material, and the patterns of the adjacent cathode wirings 5 are electrically connected at the bent portions. As a result, the cathode wiring 5 is short-circuited.

  In order to prevent this short circuit, the inside of the partition connection portion 24 is used as the vapor deposition end of the cathode wiring 5 in this embodiment. Thereby, the material of the cathode wiring 5 can be prevented from adhering to the vicinity of the region where the side surface of the partition wall 10 and the side surface of the partition wall connection portion 24 intersect. By carrying out vapor deposition using the vapor deposition mask that covers the partition wall connection portion 24 and the outside thereof, the vapor deposition end of the cathode wiring 5 can be set inside the partition wall connection portion. Further, it is desirable to design so that the deposition end of the cathode wiring 5 is disposed inside the partition wall connection portion 24 in consideration of the alignment accuracy between the mask and the substrate. That is, it is desirable to design the end of the opening of the mask on the inner side of the partition wall connection portion based on the maximum amount of displacement when the mask and the substrate are aligned. Thereby, even when the position of the mask opening is shifted by the maximum shift amount at the time of alignment, the vapor deposition end can be located inside the partition wall connection portion 24.

  A contact hole 25 is formed in the insulating film 22 in order to connect the connection wiring 21 and the cathode wiring 5 outside the display area. It is formed in a place where the cathode wiring 5 and the connection wiring 21 overlap. Since the deposition end of the cathode wiring 5 is inside the partition connection portion 24, the contact hole 25 is also formed inside the partition connection portion 24. Thereby, an electric current can be sent through the organic thin film layer sandwiched between the anode wiring 1 and the cathode wiring 5 in the opening 23, and the organic thin film layer emits light. The area where the opening 23 is provided becomes a display area, and a desired image can be displayed.

  The configuration of the element substrate having the above-described configuration will be described in detail with reference to FIGS. FIG. 2 is a top view simply showing the configuration of the end portion of the element substrate on the connection wiring side before the organic material solution (liquid organic material) is formed. FIG. 3 is a schematic view showing a configuration after application of the organic material solution. FIG. 4 is a cross-sectional view showing the configuration of the end portion of the element substrate on the connection wiring side, and shows the side surface after applying the organic material solution. FIG. 5 is a cross-sectional view showing the structure of the end portion of the element substrate on the connection wiring side, and shows a cross section taken along the line BB in FIG. 3 after forming the cathode wiring. In FIG. 2 and FIG. 3, the anode wiring 1 is omitted. Further, in FIG. 2 and FIG. 3A, the insulating film 22 outside the partition connection portion 24 is omitted.

  FIG. 2 is an enlarged view of the configuration of the end portion of the element substrate, and the right side of the drawing is the outside of the display area. As shown in FIG. 2, a plurality of partition walls 10 are arranged in parallel on an insulating film 22 covering the anode wiring 1. The partition connection portion 24 is provided between the adjacent partition walls 10 perpendicular to the partition wall 10. The partition connection part 24 is connected to the adjacent partition 10. A part of the insulating film 22 is removed between the partition walls 10, and an opening 23 corresponding to the pixel is provided. A connection wiring 21 is provided under the insulating film 22 outside the display area. The insulating film 22 on the cathode wiring 21 is removed and a contact hole 25 is provided. A dotted line in the vertical direction (a direction perpendicular to the cathode 10) shown in FIG. 2 is a vapor deposition end of the cathode wiring. That is, in a later step, the cathode wiring 5 is vapor-deposited by arranging the mask so that the inner side becomes the opening of the mask from the position of the vertical line.

  If the organic material solution 27 used as an organic thin film layer is apply | coated from above, it will become a structure shown to Fig.3 (a). In FIG. 3A, the dotted line in the vertical direction is the solution application end. The organic material solution 27 spreads along the partition wall 10 and is dammed by the partition wall connecting portion 24. Accordingly, the contact hole 25 is expanded so as to surround it. FIG. 3B is a cross-sectional view taken along line AA in FIG. 3A, and shows a cross section between the opening 23 and the partition wall 10. The organic material solution 27 spreads outside the display area along the partition wall. Therefore, the organic material solution 27 flows along the partition wall 10 and is dammed by the partition wall connecting portion 24.

  FIG. 4 is a sectional view taken along line BB in FIG. FIG. 4 shows the organic material solution 27 spreading along the partition wall 10 for the sake of explanation. The organic material solution 27 is applied to the entire display region from above the insulating film 22 through a metal mask. The application end of the organic material solution 27 is the position of the dotted line in the vertical direction in FIG. That is, the solution application end is the position of the insulating film 22 outside the outermost anode wiring 1. The organic material solution 27 spreads along the partition wall and is dammed up by the partition wall connecting portion 24. Accordingly, the height of the organic material solution 27 is increased in the vicinity of the partition wall connecting portion 24. Further, since the organic material solution 27 flows along the partition wall 10, it does not flow into the contact hole 25.

  When the organic material solution 27 is dried, the organic material is concentrated and the organic thin film layer 26 is formed. When a plurality of organic thin film layers are further formed on the organic thin film layer 26 by vapor deposition or the like, and the cathode wiring 5 is formed thereafter, the structure shown in FIG. 5 is obtained. FIG. 5 is a cross-sectional view taken along line BB in FIG. 3A after the cathode wiring is formed. The organic thin film layer 26 is formed on the insulating film 22 and is in contact with the anode wiring 1 through the opening 23. A cathode wiring 5 is disposed on the organic thin film layer 26. The portion of the organic thin film layer 26 in contact with the anode wiring 1 through the opening 23 emits light by the current flowing through the cathode and the anode. In this embodiment, the connection wiring 21 has a two-layer structure of an ITO layer and a metal layer.

  Further, a contact hole 25 is formed so that the insulating film 22 covers the connection wiring 21 with a width of 10 to 20 μm. That is, the fogging amount R of the insulating film 22 with respect to the connection wiring 21 is 10 to 20 μm, and the boundary line between the insulating film 22 and the contact hole 25 is disposed 10 to 20 μm from the end of the connection wiring 21 on the display region side. When the fogging amount R is 10 μm or less, the end portion of the connection wiring 21 may not be covered with the insulating film 22 due to the mask alignment accuracy when the connection wiring 21 and the insulating film 22 are formed. In this case, the step at the end of the connection wiring 21 is exposed, and the thickness of the cathode wiring 5 formed on the connection wiring 21 is thin. Therefore, there is a high possibility that the cathode wiring 5 is disconnected at the step. For this reason, the fogging amount R is desirably 10 μm or more.

  Further, when the fogging amount R is 20 μm or more, the area of the contact portion between the cathode wiring 5 and the connection wiring 21 becomes small. Therefore, since the connection resistance increases, a desired current cannot be passed. For this reason, the fogging amount R is desirably 20 μm or less. Via the contact hole 25, the cathode wiring 5 provided in the display area and the connection wiring 21 communicating outside the display area are electrically connected.

  A partition wall connection portion 24 is formed on the insulating film 22. The insulating film 22 below the partition wall connection portion 24 is desirably formed 5 to 10 μm wider than the partition wall connection portion 24 on the display region side. That is, the bottom surface of the insulating film 22 is formed so that the inner side is 5 to 10 μm wider than the width of the top surface of the partition wall connecting portion 24. Accordingly, the inner end portion of the insulating film 22 is disposed 5 to 10 μm inside from the inner end portion of the partition wall connection portion 24. When the thickness is 5 μm or less, the partition wall connecting portion 24 is not formed on the insulating film 22 due to the alignment accuracy. If it is 10 μm or more, the area of the contact hole 25 is reduced and the connection resistance is increased. For this reason, it is desirable that the inner end portion of the insulating film 22 be disposed 5 to 10 μm inside from the inner end portion of the partition wall connecting portion 24. Further, it is desirable that the outer end portion of the insulating film 22 is disposed outside the outer end portion of the partition wall connecting portion 24 by 5 μm or more.

  Next, the manufacturing method of the organic EL display concerning a present Example is demonstrated using FIG. FIG. 6 is a flowchart showing an example of a method for manufacturing an organic EL display according to this example.

  First, the anode wiring 1 and the connection wiring 21 are formed on the substrate 11 (step S101). As the substrate 11, for example, a transparent substrate such as a glass substrate is used. The anode wiring 1 and the connection wiring 21 are formed by depositing ITO on the substrate 11 and etching the ITO film. ITO can be formed on the entire surface of the glass substrate with good uniformity by sputtering or vapor deposition. An ITO pattern is formed by photolithography and etching. This ITO pattern becomes the anode. A phenol novolac resin is used as the resist, and exposure development is performed. Etching may be either wet etching or dry etching. For example, ITO can be patterned using a mixed aqueous solution of hydrochloric acid and nitric acid. As the resist stripping material, for example, monoethanolamine can be used.

  The connection wiring 21 can be made of a low resistance metal material such as Al or an Al alloy. For example, after patterning the ITO to be the anode wiring 1, Al or the like is formed by sputtering or vapor deposition. Alternatively, the anode wiring 1 may be formed after the connection wiring 21 is formed. Then, the connection wiring 21 can be formed by patterning the Al film by photolithography and etching. Thereby, the wiring resistance of the connection wiring can be reduced.

  Furthermore, the configuration of the connection wiring 21 may be a multilayer configuration of ITO and a metal material. For example, a metal thin film of 400 to 500 nm of Mo or Mo alloy may be formed on a 150 nm ITO layer. Thereby, wiring resistance and contact resistance can be reduced.

  Next, the insulating film 22 is formed on the surface of the substrate 11 provided with the anode wiring 1 and the connection wiring 21 (step S102). For example, a photosensitive polyimide solution is applied by spin coating. The thickness of the insulating film 22 may be set to 0.7 μm, for example. After the insulating film layer is patterned by a photolithography process, the insulating film is cured, the insulating film at a position to be a display pixel is removed, and an opening 23 is provided. The intersection of the cathode wiring 5 formed in step S105 described later and the anode wiring 1 is a position that becomes a display pixel. At the same time, contact holes between the cathode wiring 5 and the connection wiring 21 are formed. For example, the pixel opening is about 300 μm × 300 μm, and the contact hole 25 between the cathode wiring 5 and the connection wiring 21 is formed about 100 μm × 100 μm.

  Subsequently, partition walls are formed on the surface of the insulating film (polyimide layer) so that 64 cathode wirings 5 can be separated and arranged (step S103). In FIG. 1, the number of wires is reduced and shown. The partition 10 is formed by applying a photosensitive resin such as a novolac resin or an acrylic resin film on the upper layer of the insulating film. For example, a photosensitive resin is spin-coated, patterned by a photolithography process, and then photoreacted to form cathode barrier ribs. It is desirable to use a negative type photosensitive resin so that the cathode partition has an inversely tapered structure.

  When a negative photosensitive resin is used, when light is irradiated from above, the photoreaction becomes insufficient at deeper locations. As a result, when viewed from above, the cross-sectional area of the cured portion has a structure that is narrower on the lower side than on the upper side. This means that it has an inverted taper structure. With such a structure, the cathodes can be separated from each other because the portions that are shaded when viewed from the vapor deposition source during vapor deposition of the cathodes do not reach the vapor deposition. Further, in order to modify the surface of the ITO layer in the opening 23, oxygen plasma or ultraviolet light may be irradiated. For example, the height of the partition wall can be 3.4 μm.

  At the same time as the partition wall 10, a partition wall connection portion 24 connected to adjacent partition walls is formed. The partition wall connection portion 24 can be formed simultaneously by using an exposure mask having a pattern corresponding to the partition wall 10 and the partition wall connection portion 24 in the photolithography process. The partition wall connecting portion 24 can prevent the liquid organic material applied by the mask spray method in the next step from flowing out along the partition wall.

  Thereafter, an organic thin film layer is stacked (step S104). First, a metal mask having an opening is attached to a glass substrate. At this time, the metal mask opening and the organic thin film layer are disposed so as to overlap each other, and are attached so that a space of 50 μm is left between the metal mask and the glass substrate. And the ethyl benzoate solution which melt | dissolved 0.5% (mass percentage) polyvinyl carbazole was apply | coated by the mask spray method. Then, the solution is concentrated and dried to form a hole injection layer.

  Subsequently, α-NPD (N, N′-di (naphthalen-1-yl) -N, N′-diphenyl-benzidine) is deposited on the upper layer of the hole injection layer to form a hole transport layer having a thickness of 40 nm. Form. Further, Alq (tris (8-hydroxynato) aluminum) serving as the host compound of the light emitting layer and coumarin 6 serving as the fluorescent dye of the guest compound are simultaneously vapor deposited on the upper layer to form a light emitting layer having a thickness of 60 nm. Form. Subsequently, LiF is deposited on the light emitting layer to form a cathode interface layer having a thickness of 0.5 nm. As described above, when at least one of the organic thin film layers having a multilayer structure is formed of a liquid material, the unevenness of the film thickness can be reduced by the partition wall connection portion 24. Accordingly, unevenness in light emission can be reduced.

  Thereafter, a metal material such as aluminum is vapor-deposited to form a cathode wiring with a film thickness of 100 nm (step S105). As a result, the aluminum film is separated by the partition walls, and the cathode wiring 5 that intersects the anode wiring 1 can be formed between the partition walls. For example, 64 cathode wirings 5 are formed corresponding to the number of pixels.

  Next, in order to seal the organic EL light emitting element formed by the above-mentioned process, a process for manufacturing a sealing counter substrate will be described. First. A glass substrate different from the element substrate is prepared. The glass substrate is processed to form a water catching material storage for storing the water catching material. The water catching material storage part applies a resist to the glass substrate and exposes a part of the substrate by exposure and development. The exposed part is formed by etching to form a water catching material storage part.

  After arranging a water catching material such as calcium oxide in the water catching material storage part, the two substrates are overlapped and bonded (step S106). Specifically, a sealing material is applied to the surface of the counter substrate on which the water catching material storage unit is provided using a dispenser. For example, an epoxy-based ultraviolet curable resin can be used as the sealing material. The sealing material is applied to the entire outer periphery of the region facing the organic EL element. After the two substrates are aligned and face each other, the sealing material is cured by irradiating ultraviolet rays, and the substrates are bonded to each other. Thereafter, heat treatment is performed in a clean oven at 80 ° C. for 1 hour in order to further accelerate the curing of the sealing material. As a result, the sealing material and the pair of substrates separate the substrate where the organic EL element is present from the outside of the substrate. By disposing the water catching material, it is possible to prevent the organic EL element from being deteriorated due to moisture remaining or entering the sealed space.

  Unnecessary portions near the outer periphery of the substrate are cut and removed, a signal electrode driver is connected to the anode wiring 1, and a scanning electrode driver is connected to the connection wiring. A terminal portion connected to each wiring is formed at the substrate end. An anisotropic conductive film (ACF) is attached to this terminal portion, and a TCP (Tape Carrier Package) provided with a drive circuit is connected. Specifically, ACF is temporarily crimped to the terminal portion. ACF uses Hitachi Chemical Anisolm 7106U. The temporary pressure bonding temperature is 80 ° C., the pressure bonding pressure is 1.0 MPa, and the pressure bonding time is 5 seconds. Next, the TCP with the built-in drive circuit is finally bonded to the terminal portion. The main pressure bonding temperature is 170 degrees, the pressure bonding pressure is 2.0 MPa, and the pressure bonding time is 20 seconds. Thereby, a drive circuit is mounted. This organic EL display panel is attached to the housing, and the organic EL display device is completed.

  According to such a method for manufacturing an organic EL display device, the solution is prevented from spreading along the partition walls 10 when a solution of an organic material to be an organic EL element is applied. Thereby, the unevenness of the film thickness of the organic thin film layer is reduced, and the unevenness of light emission of each display pixel can be reduced when the organic EL display is driven.

  In the above-described embodiment, the vapor deposition end of the cathode wiring 5 is disposed inside the partition wall connection portion 24, but may be disposed outside the partition wall connection portion 24 as shown in FIG. In this case, the cathode wiring 5 is formed on the partition connection portion 24. Therefore, if the partition connection portion 24 has an inverse taper structure, the cathode wiring 5 is divided by the partition connection portion 24. In FIG. 7, the organic thin film layer is omitted as in FIG. In the above-described embodiments, the organic material solution is formed by spraying. However, the present invention uses liquid organic materials such as offset printing, letterpress printing, spray coating, and ink jet printing. It can be used for the method that had been.

  In the above-described embodiment, the partition connection portion 24 is provided only at the end portion of the element substrate on the connection wiring side. However, the partition substrate connection portion 24 is provided on the element substrate on the side opposite to the side where the connection wiring 21 is provided. You may provide in an edge part. That is, the structure for one cathode wiring is patterned in a square shape to form the partition connection portion 24 also on the right side of FIG. Thereby, the film thickness of an organic thin film layer can be made more uniform. Further, when the distance from the edge of the display area to the edge of the partition wall is short in the vicinity of the partition wall edge on the opposite side, the area where the coating solution spreads becomes small. Therefore, since the reduction of the film thickness in the display region hardly causes a problem, the partition wall connection portion 24 may be provided only on the connection wiring side.

It is a top view which shows the structure of the element substrate of the organic electroluminescence display concerning the Example of this invention. It is a top view which shows the structure of the element substrate edge part before the organic material solution application | coating of the organic electroluminescent display apparatus concerning the Example of this invention. It is the schematic which shows the structure of the element substrate edge part after the organic material solution application | coating of the organic electroluminescent display apparatus concerning the Example of this invention. It is an expanded sectional view which shows the structure of the element substrate edge part after the organic material solution application | coating of the organic electroluminescent display apparatus concerning the Example of this invention. It is an expanded sectional view which shows the structure of the element substrate edge part after cathode wiring formation of the organic electroluminescent display apparatus concerning the Example of this invention. It is a flowchart which shows the manufacturing process of the organic electroluminescent display apparatus concerning the Example of this invention. It is a top view which shows another structure of the element substrate of the organic electroluminescence display concerning the Example of this invention. It is sectional drawing which shows the structure of the element substrate of the conventional organic electroluminescence display. It is a figure which shows the structure of the element substrate of the conventional organic EL display apparatus. It is a figure which shows the state which the solution of the organic material spread along the partition.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Anode wiring 5 Cathode wiring 10 Partition 11 Substrate 21 Connection wiring 22 Insulating film 23 Opening 24 Partition connection 25 Contact hole 26 Organic thin film layer 27 Organic material solution

Claims (9)

A first electrode formed on a substrate;
A plurality of barrier ribs formed to intersect the first electrode;
A partition wall connecting portion provided between the adjacent partition walls and connected to the adjacent partition wall;
An organic compound layer formed by applying a liquid material on the first electrode;
An organic EL display device comprising: a second electrode separated by the partition on the organic compound layer. A connection wiring that is formed under the partition wall connection portion so as to intersect with the partition wall connection portion and is electrically connected to the second electrode,
The organic EL display device according to claim 1, wherein an end portion of the second electrode is formed inside the partition connection portion. A plurality of the partition connection portions are provided corresponding to the plurality of second electrodes,
The organic EL display device according to claim 1, wherein the plurality of partition wall connection portions are arranged in a substantially line.   The organic EL display device according to claim 1, wherein the partition wall and the partition wall connection portion are formed of the same material.   The organic EL display device according to claim 1, wherein the partition wall connection portion is formed outside a display region. Forming a first electrode on a substrate;
Forming a plurality of barrier ribs intersecting the first electrode on the first electrode;
Providing a partition connecting portion connected to the adjacent partition;
Forming an organic compound layer by applying a liquid material on the first electrode; and
Forming a second electrode separated by the partition on the organic compound layer.   The method for manufacturing an organic EL display device according to claim 6, wherein the partition wall and the partition wall connection portion are formed substantially simultaneously. Forming a connection wiring crossing the partition wall connection portion and electrically connecting to the second electrode below the partition wall connection portion;
8. The method of manufacturing an organic EL display device according to claim 6, wherein in the step of forming the second electrode, the second electrode is formed inside the partition connection portion. 9. A plurality of the partition connection portions are provided corresponding to the plurality of second electrodes,
The method for manufacturing an organic EL display device according to claim 6, wherein the plurality of partition wall connection portions are arranged in a substantially line.

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