KR100592387B1 - Electro-luminescence display panel and manufacturing method therefor - Google Patents

Abstract

The present invention provides an EL display panel and a manufacturing method thereof capable of preventing short defects due to metal residues.

To this end, in the EL display panel of the present invention, the first electrode includes a metal electrode having a relatively small line width formed on the substrate; A transparent electrode having a relatively wide line width is provided on the metal electrode.

Description

ELECTROLUMINESCENCE DISPLAY PANEL AND METHOD FOR FABRICATING THE SAME             

1 is a diagram showing the structure of a conventional organic EL display panel.

FIG. 2 is a cross-sectional view of the organic EL display panel shown in FIG. 1.

3A and 3B are plan and cross-sectional views illustrating in detail the structure of the first electrode illustrated in FIG. 1.

4A and 4B are a plan view and a cross-sectional view illustrating in detail a first electrode structure of an organic EL display panel according to an exemplary embodiment of the present invention.

FIG. 5 is a cross-sectional view illustrating a method of manufacturing the first electrode illustrated in FIG. 4B in stages. FIG.

<Description of Symbols for Main Parts of Drawings>

2, 22: substrate 4, 24: first electrode

6: insulating film 8: partition wall

10 organic light emitting layer 12 second electrode

14, 26: metal residue 4A, 24B: transparent electrode

4B, 24A: auxiliary electrode

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electroluminescent display panel, and more particularly, to an electroluminescent display panel capable of preventing defects due to metal residues and a method of manufacturing the same.

Various flat panel display devices that can reduce weight and volume, which are disadvantages of cathode ray tubes, are emerging. Such flat panel displays include a liquid crystal display, a field emission display, a plasma display panel, and an electro-luminescence (hereinafter, EL). And a display panel.

Among them, an EL display panel is a self-luminous element that emits a phosphor by recombination of electrons and holes, and is classified roughly into an inorganic EL using an inorganic compound and an organic EL using an organic compound as the phosphor. Such EL display panels have many advantages such as low voltage driving, self-luminous, thin film type, wide viewing angle, fast response speed, and high contrast, and are expected to be the next generation display devices.

The organic EL element is usually composed of an electron injection layer, an electron transport layer, a light emitting layer, a hole transport layer, and a hole injection layer stacked between a cathode and an anode. In such an organic EL device, when a predetermined voltage is applied between the anode and the cathode, electrons generated from the cathode move toward the light emitting layer through the electron injection layer and the electron transport layer, and holes generated from the anode move into the hole injection layer and the hole transport layer. Move toward the emitting layer through. Accordingly, the light emitting layer emits light by recombination of electrons and holes supplied from the electron transporting layer and the hole transporting layer.

An EL display panel using such an organic EL element includes an organic light emitting layer 10 formed at each intersection of the first electrode 4 and the second electrode 12, as shown in Figs.

The first electrode (anode) 4 using a transparent conductive material (ITO, etc.) electrode is formed side by side separated by vertical lines on the substrate 2. On the substrate 2 on which the first electrode 4 is formed, an insulating film 6 having an opening for each effective light emitting area is formed. On the insulating film 6, a partition wall 8 for separating the second electrode (cathode) 12 to be formed later by horizontal lines is formed. To this end, the partition wall 8 is formed in a direction crossing the first electrode 4 and has an overhag structure in which the upper end portion has a wider width than the lower end portion. R, G, and B light emitting layers 10 made of an organic compound are formed in the opening of the insulating layer 6 to which the first electrode 4 is exposed. The R, G, and B light emitting layers 10 are sequentially formed in the light emitting region through a deposition method through a shadow mask of a corresponding color. In addition, a metal material is entirely deposited on the substrate 2 on which the R, G, and B light emitting layers 10 are formed to form a second electrode 12 separated by horizontal lines by the partition wall 8.

Here, since the first electrode 4 is formed of a transparent conductive material to transmit light generated from the light emitting layer 10, the first electrode 4 has a relatively large resistance component, which causes signal attenuation. To compensate for this, the second electrode 4 further comprises an auxiliary electrode of a metallic material which can compensate for the large resistance of the transparent conductive material.

For example, the first electrode 4 is formed in a structure in which the transparent electrode 4A and the metal electrode 4B are stacked as shown in FIGS. 3A and 3B. The transparent electrode 4A that transmits light is formed to have a relatively wide line width, and the metal electrode 4B is formed to have a relatively narrow line width deviated to one side on the transparent electrode 4A to minimize light blocking.

Looking at the manufacturing method of the first electrode 4 having such a structure as follows.

First, a transparent conductive material is entirely deposited on the substrate 2 and patterned by a photolithography process and an etching process using a first mask to form transparent electrodes 4A separated by vertical lines. Subsequently, a metal material is entirely deposited on the substrate 2 on which the transparent electrode 4A is formed, and then patterned by a photolithography process and an etching process using a second mask so that the metal electrode 4B having a small line width on the transparent electrode 4A is formed. This is biased to one side. At this time, when the metal electrode 4B is patterned, the metal residue 14 remains on the transparent electrode 4A and the substrate 2, and the metal residue 14 is formed on the second electrode to be formed in a subsequent process. It will cause a short defect.

Accordingly, it is an object of the present invention to provide an EL display panel and a manufacturing method thereof capable of preventing short defects due to metal residues.

In order to achieve the above object, in the EL display panel according to the present invention, the first electrode comprises: a relatively small line width metal electrode formed on a substrate; A transparent electrode having a relatively wide line width is provided on the metal electrode.

The transparent electrode is formed to completely cover the metal electrode.

The metal electrode is formed to be biased toward one side of the transparent electrode.

The forming of the first electrode in the method of manufacturing an EL display panel according to the present invention includes forming and patterning a metal film on a substrate to form a metal electrode having a relatively small line width; Forming and patterning a transparent conductive film on the substrate on which the metal electrode is formed to form a transparent electrode having a relatively wide line width on the metal electrode.

The metal residues remaining on the substrate when the metal electrode is formed are covered with the transparent electrode or removed with an etchant used when patterning the transparent electrode.

Other objects and features of the present invention in addition to the above objects will become apparent from the description of the embodiments with reference to the accompanying drawings.

Hereinafter, exemplary embodiments of the present invention will be described with reference to FIGS. 4A to 5.

4A and 4B are a plan view and a sectional view showing the first electrode structure of the EL display panel according to the embodiment of the present invention.

4A and 4B, the first electrode 24 formed on the substrate 22 includes a metal electrode 24A having a small line width and a transparent electrode 24B formed at a wide line width on the metal electrode 24A. The metal electrode 24A is formed to be biased toward one side of the transparent electrode 24B to minimize light blocking, and the transparent electrode 24B is formed to have a structure covering the metal electrode 24A. Accordingly, the metal residue remaining after the metal electrode 24A is formed is removed during the formation of the transparent electrode 24B, which is a subsequent process, or covered by the transparent electrode 24B, thereby preventing short defects due to the metal residue.

FIG. 5 is a cross-sectional view for describing a method of manufacturing the first electrode 23 illustrated in FIG. 4B.

First, a metal material is entirely deposited on the substrate 22 and patterned by a photolithography process and an etching process using a first mask to form a metal electrode 24A having a relatively small line width.

Subsequently, a transparent conductive material is entirely deposited on the substrate 22 on which the metal electrode 24A is formed, and is patterned by a photolithography process and an etching process using a second mask to have a wide line width on the metal electrode 24A. ) Is formed. Each of the transparent electrodes 24B is formed to have a structure completely covering the metal electrode 24A formed to be biased to one side. In this case, the metal residue 26 remaining on the substrate 22 when forming the metal electrode 24A is blocked by the transparent electrode 24B formed thereon or etched by the etchant of the transparent electrode 24B. Removed. Accordingly, short defects with the second electrode to be formed in a subsequent process due to the metal residue 26 can be prevented.

As described above, the EL display panel and the manufacturing method according to the present invention form a transparent electrode of the first electrode on the metal electrode of the first electrode so that the metal residue can be covered with the transparent electrode or removed with an etchant of the transparent electrode. do. Therefore, short defects with the second electrode due to the metal residue of the first electrode can be prevented.

Those skilled in the art will appreciate that various changes and modifications can be made without departing from the technical spirit of the present invention. Therefore, the technical scope of the present invention should not be limited to the contents described in the detailed description of the specification but should be defined by the claims.

Claims (7)

In an EL display panel including a light emitting layer formed between a first electrode and a second electrode, the first electrode may include a light emitting layer. A relatively small line width metal electrode formed on the substrate; A transparent electrode formed to completely cover the metal electrode with a relatively wide line width on the metal electrode, And the metal electrode is formed to be biased toward one side of the transparent electrode. delete delete In the method of manufacturing an electro-luminescence (EL) display panel including a light emitting layer formed between a first electrode and a second electrode, the forming of the first electrode may be performed. Forming and patterning a metal film on the substrate to form a metal electrode having a relatively small line width; Forming a transparent conductive film on the substrate on which the metal electrode is formed and patterning the transparent electrode so as to completely cover the metal electrode with a relatively wide line width on the metal electrode; And the metal electrode is formed to be biased toward one side of the transparent electrode. delete delete The method of claim 4, wherein Metal residues remaining on the substrate when the metal electrode is formed And covering with the transparent electrode or removed with an etchant used when patterning the transparent electrode.

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