JP2007234819A - Organic electroluminescence display, and method for manufacturing organic electroluminescence display - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To make it hard the occurrence of disconnection of the interconnection of one side in an organic electroluminescence display in which the interconnection of one side is electrically connected to the interconnection of another side, by forming a riding-on portion where the interconnection of one side rides on the interconnection of another side. <P>SOLUTION: After depositing an ITO on a glass substrate 10, the ITO is etched to form a positive electrode interconnection 1. Then, the surface of the ITO is polished. Since the patterning of the ITO is already carried out, in other words, the positive electrode interconnection 1 is already formed, the corners of the positive electrode interconnection 1 is also polished. Stated differently, the portion uprising toward the corner Q in the positive electrode interconnection 1 is processed into a taper shape having inclination not uprising vertically from a flat portion, and, the corner deforms into a roundish shape. Then a metal film of aluminum etc. is deposited in the upper layer of the positive electrode interconnection 1, and the metal film is etched to form the positive electrode drawn-around interconnection 11. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

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

  In an organic EL (electroluminescence) display device, an anode wiring connected to the anode or forming the anode itself, and a cathode wiring connected to the cathode or forming the cathode itself are opposed to each other, and Provided to intersect. In general, the cathode wiring is formed of metal, and the anode wiring is formed of a transparent conductive film such as ITO (indium / tin / oxide). An organic thin film (organic EL layer) is disposed between the anode wiring and the cathode wiring. The organic EL display device is a current-driven display device that emits light when a current is supplied to the organic thin film disposed between the anode wiring and the cathode wiring. In the organic EL panel in which the anode wiring and the cathode wiring are arranged in a matrix, the intersection of the anode wiring and the cathode wiring is a pixel. That is, the pixels are arranged in a matrix. The organic EL element is formed of an anode wiring and a cathode wiring and an organic thin film existing between them. When the anode wiring side is set to the high voltage side and a predetermined voltage is applied between both electrode wirings to supply current to the organic thin film, light is emitted. Conversely, when the cathode wiring side is at a high potential, no current flows and no light is emitted.

  The organic EL element is formed on a substrate such as a glass substrate, and generally, a drive circuit for driving the organic EL element is mounted on the substrate (see, for example, Patent Document 1). Therefore, a wiring for transmitting the signal from the drive circuit to the cathode and the anode by connecting the cathode and the anode in the organic EL element to the drive circuit is provided on the glass substrate. Hereinafter, the wiring connecting the cathode and the drive circuit is referred to as a cathode routing wiring, and the wiring connecting the anode and the drive circuit is referred to as an anode routing wiring.

Japanese Patent Laying-Open No. 2005-164679 (paragraph 0027, FIG. 1)

  FIG. 4A is a plan view illustrating a part of a configuration example of the organic EL display device, and FIG. 4B is a cross-sectional view illustrating a BB cross section. In the organic EL display device shown in FIG. 4, anode wiring 1 made of a transparent conductive film (for example, ITO) is formed on a glass substrate 10. An organic thin film 9 is laminated on the anode wiring 1 (on the side opposite to the glass substrate 10), and a cathode wiring 2 made of a metal such as Al is formed on the organic thin film 9. The anode wiring 1 and the cathode wiring 2 are insulated by an insulating film 8. Further, partition walls 16 are formed for separating the respective cathode wirings 2. An insulating film hole 17 is provided in the insulating film 8, and the cathode wiring 2 and the cathode routing wiring 13 are electrically connected through the insulating film hole 17. In addition, an insulating film hole 15 for forming an opening to be a light emitting portion of each pixel is also formed.

  As shown in FIG. 4, the cathode wiring 2 is connected to the cathode routing wiring 13, while the anode wiring 1 is connected to the anode routing wiring (not shown in FIG. 4). FIG. 5A is a plan view showing an example of how to connect the anode wiring 1 and the anode routing wiring 11, and FIG. 5B is a cross-sectional view showing a BB cross section. In the example shown in FIG. 5, the anode routing wiring 11 is formed by forming a wiring 11A made of a metal such as Al on an ITO portion 11B obtained by extending ITO forming the anode wiring 1. Then, the wiring 11A is connected to the drive circuit.

  When the connection method shown in FIG. 5 is used, that is, when the anode routing wiring 11 in which the ITO portion 11B is present below the metal wiring 11A is used, the interval between the wirings 11A becomes large.

  FIG. 6 is an explanatory diagram for explaining the interval between the wirings 11A. In order to form the anode routing wiring 11 in which the ITO portion 11B exists under the metal wiring 11A, first, the ITO is patterned to form the ITO portion 11B, and then the metal is formed, It is necessary to form the wiring 11A by patterning. Then, as shown in FIG. 6A, the width of the wiring 11A cannot be made larger than the width of the ITO portion 11B. Further, it is necessary to provide a margin between the two ITO parts 11B. As a result, as shown in FIG. 6B, the distance a between the wirings 11A shown in FIG. 6A is larger than the distance b between the wirings 11A when the anode routing wiring 11 is formed only by the metal wiring 11A. Become.

  In the organic EL display device, it is desirable that the distance between the wirings 11 </ b> A is small because the area of the portion that does not contribute to the display (so-called frame portion) can be made smaller than the portion that actually contributes to the display.

  FIG. 7 is a plan view showing a part of the organic EL display device in which the anode lead-out wiring 11 is formed of only metal, and FIG. 7B is a cross-sectional view showing a BB cross section.

  When the anode lead-out wiring 11 is formed only by the metal wiring 11A, as shown in FIG. 7B, the structure is such that the metal wiring 11A rides on the ITO portion where the anode wiring 1 is formed. . As a result, the corner portion Q exists in the portion P where the metal is on the step portion in the anode wiring 1. In the portion P, disconnection of the anode lead-out wiring 11 (wiring 11A) is more likely to occur than in the portion R where the metal is on the flat portion of the anode wiring 1 formed of ITO. FIG. 8 is a cross-sectional view schematically showing a state in which disconnection occurs.

  That is, when the anode routing wiring 11 is formed only of metal, the anode routing wiring 11 is compared with the case where the anode routing wiring 11 is formed of the ITO portion and the metal as shown in FIG. However, the disconnection is likely to occur. Since the disconnection is likely to occur, there is a problem that the yield at the time of manufacturing the organic EL display device is lowered and the productivity is lowered.

  Therefore, the present invention provides an organic EL display device in which a run-up portion on which the other wiring rides on one wiring is formed and the one wiring and the other wiring are electrically connected to each other. The purpose is to make it difficult to occur.

  Further, in an organic EL display device having a structure in which a run-up portion on which the anode routing wiring runs is formed on the anode wiring and the anode wiring and the anode routing wiring are electrically connected to each other, the disconnection of the anode routing wiring is less likely to occur. An object of the present invention is to provide an organic EL display device and a method for manufacturing the organic EL display device.

  An organic EL display device according to the present invention includes a first wiring formed of a transparent conductive film, an organic EL layer, and a second wiring formed of a metal, and includes a first wiring and a second wiring. An organic EL display device having a structure in which a run-up portion on which one of the other wires rides on one of the wires and the one and the other wires are electrically connected to each other is provided. The rising part in the wiring is inclined, and the upper part of the rising part is formed in a rounded shape.

  Another embodiment of the organic EL display device according to the present invention includes an anode wiring formed of a transparent conductive film, an organic EL layer, and a cathode wiring, and an anode routing wiring that is formed of metal and transmits a signal to the anode wiring. An organic EL display device having a structure in which the rising portion is formed in the anode wiring and the anode wiring and the anode routing wiring are electrically connected, the rising portion in the anode wiring is inclined at the climbing portion, and The upper part of the rising part is formed in a rounded shape.

  The method for manufacturing an organic EL display device according to the present invention includes an anode wiring formed of a transparent conductive film, an organic EL layer, and a cathode wiring, and an anode routing wiring that is formed of metal and transmits a signal to the anode wiring. A manufacturing method for manufacturing an organic EL display device having a structure in which a rising portion is formed in an anode wiring and the anode wiring and the anode lead-out wiring are electrically connected, and the transparent conductive film formed on the substrate is patterned Then, the anode wiring is formed, the rising part of the anode wiring is inclined at the rising part, and the upper part of the rising part is processed into a rounded shape, and is electrically connected to the anode wiring at the rising part. As described above, the metal formed on the upper layer of the anode wiring is patterned to form an anode routing wiring.

  According to the present invention, since the rising portion of one wiring is inclined and the upper portion of the rising portion is formed in a rounded shape, it is possible to prevent disconnection of the other wiring that rides on one wiring. it can.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(Embodiment 1)
FIG. 1 is a flowchart showing a method for manufacturing an organic EL display device according to a first embodiment (Embodiment 1) of the present invention. Hereinafter, the organic EL display device is referred to as an organic EL panel. Note that the structure of the formed organic EL panel is, for example, as shown in FIG. Therefore, in the following description, the reference numerals attached in FIG.

  As shown in FIG. 1, first, an ITO film is formed on a substrate (glass substrate 10) (step S1), and then the ITO is patterned (step S2). Specifically, the anode wiring 1 is formed by etching ITO. Next, the ITO surface is polished (step S3).

  As a polishing method, a mechanical polishing method or a chemical polishing method may be used. For example, the surface of ITO is polished by applying a polishing cloth supplied with an abrasive to a substrate patterned with ITO and mechanically rotating the polishing cloth or the substrate. Since the ITO has already been patterned, that is, the anode wiring 1 is formed, the corners of the anode wiring 1 are also polished. That is, a portion (for example, see the portion P in FIG. 7B) that rises toward the corner (for example, the corner Q in FIG. 7B) of the anode wiring 1 rises vertically from the flat portion. Instead, it is processed into a tapered shape having a slope, and the corners are rounded (the cross section is a part of a circle, a part of an ellipse, or a shape other than those).

  Next, a metal film such as Al is formed on the upper layer of the anode wiring 1 (step S4), and the metal film is etched to form the anode routing wiring 11 and the cathode routing wiring 13 (step S5).

  Further, an insulating film 8 made of a photosensitive polyimide resin is applied on the member layer formed of a metal film. The insulating film 8 is a structure whose opening defines the light emitting region of the organic EL panel. Then, an insulating film hole 15 is formed in order to form an opening to be a light emitting portion of each pixel in the organic EL panel by performing exposure development and the like. When forming the opening in the organic EL panel, the insulating film at a predetermined portion of the cathode lead-out wiring 13 is removed to form the insulating film hole 17 (step S6).

  Further, after applying a negative type photosensitive resin (a portion exposed to light at the time of exposure) is applied, exposure and development are performed to form the partition 16 (step S7). The formed barrier ribs 16 separate the cathode wirings 2 formed by vapor deposition in the subsequent process. Further, the cathode lead wiring 13 is also separated by the partition wall 16. On the substrate on which the anode wiring 1 and the like are formed as described above, the organic thin film 9 as the organic EL layer is laminated by vapor deposition (step S8). As the organic thin film 9, a hole injection layer, a hole transport layer, a light emitting layer, an electron transport layer, and an electron injection layer are sequentially formed. Next, the cathode wiring 2 is formed of a metal such as aluminum by vapor deposition (step S9). The cathode wiring 2 is electrically connected to the cathode lead wiring 13 at the portion of the insulating film hole 17.

  And in the sealing process of step S10, in order to protect the organic EL layer formed on the glass substrate 10 from moisture, another glass substrate as a second substrate is disposed opposite to the glass substrate. Both glass substrates are joined by a sealing material as a gap material. Then, dry nitrogen gas is sealed in the sealed space formed by the two glass substrates and the sealing material.

  FIG. 2 is a plan view showing a part of the organic EL panel manufactured by the manufacturing method of the present embodiment, in which the anode lead-out wiring is formed only with metal, and FIG. FIG. 4 is a sectional view showing a BB section.

  As shown in FIG. 2B, the anode lead-out wiring 11 has a structure that rides on the anode wiring 1 formed of ITO. However, in the structure shown in FIG. 2, unlike the structure shown in FIG. 7, the corner portion Q of the anode wiring 1 is changed to a rounded shape in the portion P where the step is formed.

  In the structure shown in FIG. 7, the corner portion Q of the anode wiring 1 has an angular shape in the portion P where the step is formed, and therefore the disconnection of the anode routing wiring 11 is likely to occur. However, in the present embodiment, the anode wiring 1 has a rounded shape in the portion P where the step is formed, and therefore the disconnection of the anode routing wiring 11 is less likely to occur.

(Embodiment 2)
In the above-described embodiment, a structure in which a metal wiring runs on the wiring 1A formed of a transparent conductive film (ITO in the above example) and the wiring by the transparent conductive film and the metal wiring are electrically connected is provided. Take an example. However, as shown in FIG. 3, the metal wiring is formed first, and then formed so that the wiring 1A made of a transparent conductive film such as ITO rides on, and the metal wiring and the wiring made of the transparent conductive film are electrically connected. The present invention can be applied to an organic EL panel having a structure.

  In that case, after the metal film is patterned to form a metal wiring or the like, the metal wiring or the like is polished before the transparent conductive film is formed. A mechanical polishing method can be used as the polishing method. For example, metal wiring or the like can be polished by using alumina or the like as an abrasive and using a polishing cloth.

  Also in this case, it is preferable to polish the metal wiring or the like so that the portion rising toward the corner is processed into a tapered shape and the corner is deformed into a rounded shape.

  In each of the above embodiments, the case where polishing is used to round the corners of the anode wiring 1 or the metal wiring is taken as an example. However, other methods may be used as long as the corners can be rounded.

  As described above, in the first and second embodiments, the wiring formed of the transparent conductive film and the metal wiring are electrically connected, and one wiring is connected to the other wiring. In the organic EL panel having a structure that rides up, before forming the wiring provided in the upper layer, the portion rising toward the corner Q on the wiring formed in the lower layer is formed in a tapered shape, and the corner is Since it is processed into a rounded shape, disconnection of the upper wiring can be made difficult to occur.

  In particular, as in the first embodiment, a portion of the anode wiring 1 formed of ITO that rises toward the corner Q is formed into a tapered shape, and the corner Q is processed into a rounded shape. In this case, the disconnection of the anode lead-out wiring 11 can be made difficult to occur.

  As a result, the yield at the time of manufacturing the organic EL panel is increased, so that productivity is improved. In addition, since the anode routing wiring 11 is formed of only metal, it is possible to maintain the effect of reducing the intervals between the many anode routing wirings 11. Therefore, the area occupied by a large number of anode routing wirings 11 can be reduced, and the area of a portion that does not contribute to display (so-called frame portion) can be reduced. Further, since the interval between the anode routing wirings 11 can be reduced, the width of the anode routing wiring 11 can be increased when the area occupied by a large number of anode routing wirings 11 is maintained. That is, it is possible to reduce the resistance value of the anode routing wiring 11 by increasing the area of each anode routing wiring 11 itself.

  When the organic EL display device according to the first embodiment is manufactured, the end surface of the anode wiring 1 formed of ITO is polished by polishing (inclined toward the corner Q in the cross-sectional view of FIG. 2B). When the slope of the surface represented by the line rising to 12 to 15 degrees (the direction of the plane parallel to the surface of the glass substrate 10 is set to 0 degree), disconnection of the anode lead-out wiring 11 hardly occurs. It was confirmed that In addition, when not polishing, that is, when a conventional method for manufacturing an organic EL display device was used, the slope of the end surface of the anode wiring 1 was 26 to 27 degrees, and disconnection occurred. Therefore, it is considered that when the inclination is about 20 degrees or less, the disconnection of the anode lead-out wiring 11 is less likely to occur.

  The present invention is effectively applied to an organic EL panel having a structure in which a wiring formed of a transparent conductive film and a metal wiring are electrically connected.

5 is a flowchart showing a method for manufacturing an organic EL display device according to the present invention. (A) is a top view which shows a part of organic electroluminescent display device in which the anode lead wiring was formed only with the metal, (B) is sectional drawing which shows a BB cross section. Sectional drawing which shows 2nd Embodiment. (A) is a top view which shows a part of organic EL display apparatus as an example, (B) is sectional drawing which shows a BB cross section. (A) is a top view which shows an example of the connection method of the anode wiring 1 and anode routing wiring, (B) is sectional drawing which shows a BB cross section. Explanatory drawing for demonstrating the space | interval of wiring. (A) is a top view which shows a part of organic electroluminescence display in which anode lead wiring was formed only with the metal in case this invention is not applied, (B) is sectional drawing which shows a BB cross section. Sectional drawing which shows typically a mode that the disconnection has arisen in the anode routing wiring.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Anode wiring 2 Cathode wiring 8 Insulating film 9 Organic thin film 10 Glass substrate 11 Anode routing wiring 11A wiring 11B ITO part 13 Cathode routing wiring 15 Insulating film hole 16 Partition 17 Insulating film hole

Claims (3)

A first wiring formed of a transparent conductive film, an organic EL layer, and a second wiring formed of metal, wherein one of the first wiring and the second wiring is connected to the other wiring; In an organic EL display device having a structure in which a climbing portion on which the cable rides is formed and one wiring and the other wiring are electrically connected,
An organic EL display device, wherein a rising portion of the one wiring is inclined at the climbing portion, and an upper portion of the rising portion is rounded. An anode wiring formed of a transparent conductive film, an organic EL layer, and a cathode wiring, and a run-up portion on which an anode routing wiring that is formed of metal and transmits a signal to the anode wiring rides is formed on the anode wiring, and In the organic EL display device having a structure in which the anode wiring and the anode routing wiring are electrically connected,
An organic EL display device, wherein the rising portion of the anode wiring is inclined and the upper portion of the rising portion is rounded at the climbing portion. An anode wiring formed of a transparent conductive film, an organic EL layer, and a cathode wiring, and a run-up portion on which an anode routing wiring that is formed of metal and transmits a signal to the anode wiring rides is formed on the anode wiring, and In a manufacturing method of manufacturing an organic EL display device having a structure in which an anode wiring and the anode routing wiring are electrically connected,
Patterning a transparent conductive film formed on a substrate to form the anode wiring;
In the climbing part, the rising part in the anode wiring is inclined, and the upper part of the rising part is processed into a rounded shape,
Manufacturing the organic EL display device, wherein the anode lead-out wiring is formed by patterning a metal film formed on an upper layer of the anode wiring so as to be electrically connected to the anode wiring at the climbing portion. Method.

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