JPH0773809A - Display element - Google Patents

Abstract

PURPOSE:To prevent a bus electrode from being put afloat when covering is made with an insulative layer to cause impossibility of generating electric continuity with a transparent electrode and to easily make displaying of high fineness through removing of difficult processes otherwise required according to the conventional technique. CONSTITUTION:A metal bus electrode 2 is formed on a front face base board 1 and covered with a transparent electrode 3, and these two electrodes 2, 3 are covered with an insulative layer 4 consisting of a low melting point lead glass. This precludes risk of glass intrusion between the electrodes 2 and 3.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a display device, and more particularly to a display device used for information display terminals, flat screen televisions and the like.

[0002]

2. Description of the Related Art A plasma display panel is a display device having a structure in which a transparent electrode and a metal bus electrode are covered with a thick glass film. This plasma display panel includes a monochrome panel that uses the emission color of Ne and a color panel that uses the emission color of phosphor. This color plasma display panel is expected as a display element used for information terminals, flat-screen televisions and the like. A color plasma display panel is a display that excites and emits a fluorescent substance by ultraviolet rays generated by gas discharge to obtain visible light and performs a display operation.
It can be classified into C type. Among the AC types, the reflection type AC surface discharge type is superior in brightness, luminous efficiency, and life.

FIG. 2 is a cross-sectional view of an essential part of an example of a conventional reflection type AC surface discharge type plasma display panel. As shown in FIG. 2, first, a plurality of transparent electrodes 3 are formed on the glass front substrate 1. Normally, a pulsed AC voltage of several tens of kHz to several hundreds of kHz is applied between the adjacent transparent electrodes 3 to obtain a display discharge. However, the tin oxide film usually used for the transparent electrode 3 has a sheet resistance of Since it is as high as several tens of Ω / □, the electrode resistance becomes several tens of kΩ particularly in a large-sized panel or a high-definition panel, and the applied voltage pulse does not rise sufficiently to make driving difficult. Therefore, the bus electrode 2 which is usually made of a thick metal film is formed on the transparent electrode 3 to reduce the resistance value of the electrode. Next, the transparent electrode 3 and the bus electrode 2 are covered with an insulating layer 4. The insulating layer 4 is usually a thick film made of low melting point lead glass. However, 600 ° C for forming thick film of low melting point lead glass
A baking process is required to some extent. At this time, the softened low-melting lead glass penetrates between the bus electrode 2 and the transparent electrode 3 due to a thick metal film or the like, and the bus electrode 2 floats in the insulating layer 4. Therefore, electrical contact between the transparent electrode 3 and the bus electrode 2 cannot be established. Therefore, the function of the bus electrode 2 is not fulfilled. This occurs because the adhesion strength between the thick conductive film and the transparent conductive film of tin oxide that is usually used for the transparent electrode is weak. In order to prevent this phenomenon, a small hole is formed in a part of the transparent electrode 3 so that a part of the bus electrode 2 directly contacts the front substrate 1. Since the front substrate 1 is a glass plate, it has high adhesion to a thick metal film, and the bus electrode 2 does not float up even in the firing process of forming the insulating layer 4 of low melting point lead glass, and the electric conductivity of the bus electrode 2 and the transparent electrode 3 is not increased. Physical contact is secured. Next, the protective layer 5 is formed on the insulating layer 4. Protective layer 5
Is formed of, for example, a thin film of MgO or a thick film.

On the other hand, a data electrode 10 for writing display data is formed on the rear substrate 11 and is covered with an insulating layer 9. Further, a fluorescent material 8 of a luminescent color of each pixel is formed in a portion which becomes each pixel.
Apply. A gas that can be discharged inside, for example, a mixture of He and Xe, is adhered to the rear substrate 11 via the black partition wall 6 formed on the front substrate 1 and the white partition wall 7 formed on the rear substrate 11 to hermetically seal them. Enclose the gas at about 300 torr. When a pulsed AC voltage is applied between the adjacent transparent electrodes 3, gas discharge occurs and plasma is generated in the discharge cell. The ultraviolet light generated here excites the phosphor 8 to generate visible light, and display light emission is obtained through the front substrate 1.

[0005]

In this conventional display element, when a bus electrode is formed on a transparent electrode and covered with a low melting point lead glass, the bus electrode floats away from the transparent electrode, A small hole is formed in the transparent electrode in order to prevent the electrical connection between the transparent electrode and the transparent electrode from becoming unsecured. Was difficult to form. Further, there is a drawback that the yield is reduced because the pattern becomes complicated. These become remarkable especially in a high-definition panel having a narrow electrode width.

The object of the present invention is to ensure the electrical connection between the bus electrode and the transparent electrode without the bus electrode separating from the transparent electrode and floating, and to easily obtain a high-definition display without the need to form small holes. It is to provide a display element.

[0007]

A display device of the present invention covers a glass substrate, a metal bus electrode formed on the glass substrate, a transparent electrode for covering the metal bus electrode, and a transparent electrode for covering the transparent electrode. And an insulating layer made of a thick glass film.

[0008]

Function: A bus electrode is formed on a glass substrate, and this is covered with a transparent electrode. The bus electrode is in direct contact with the glass substrate and is further covered with a transparent electrode. Therefore, without using the difficult process of forming a small hole in the transparent electrode,
When these are covered with an insulating layer of low melting point lead glass, the low melting point lead glass does not enter between the bus electrode and the transparent electrode, and electrical contact is secured.

[0009]

Embodiments of the present invention will now be described with reference to the drawings.

FIG. 1 is a sectional view of the essential portions of an embodiment of the present invention. As shown in FIG. 1, the basic structure is the same as that of the conventional example shown in FIG. 2, except that a bus electrode 2 is formed between the transparent electrode 3 and the front substrate 1, and a small hole is formed in the transparent electrode 3. The difference is that it is not formed. The bus electrode 2 is formed of a thick film of silver, for example. The thick silver film has very high adhesion to the glass substrate and is difficult to peel off. Further, the bus electrode 2 is formed of, for example, a transparent conductive film obtained by doping tin oxide with a slight amount of antimony.
Formed and coated by VD. After patterning this transparent conductive film into an electrode shape to form the transparent electrode 3,
A low melting point lead glass powder is applied by, for example, screen printing, and is baked at a temperature of about 600 ° C. to form the insulating layer 4. At this time as well, the bus electrode 2 is in close contact with the front substrate 1 and is further covered with the transparent electrode 3, so that the bus electrode 2 floats in the low melting point lead glass layer of the insulating layer 4 and electrical connection is made. It is no longer lost.
Therefore, the process of forming a small hole in the transparent electrode 3 of tin oxide, which is very difficult, becomes unnecessary.

In this embodiment, the structure in which the bus electrode 2 is completely covered with the transparent electrode 3 is taken as an example, but the structure in which a part of the bus electrode 2 is covered with the transparent electrode 2 is similar. It goes without saying that the effects can be obtained.

The present invention also provides a transparent electrode other than tin oxide,
For example, it is effective for ITO and the like, and the metal bus electrode is not limited to a thick metal film, but is effective for thin films of aluminum, chrome-copper-chrome, etc.

Further, although the plasma display panel has been described as an example in the present embodiment, it can be applied to a fluorescent display tube and the like.

[0014]

As described above, according to the present invention, the metal bus electrode is formed on the front substrate, and the metal bus electrode is covered with the transparent electrode, so that the transparent electrode is covered with the low melting point lead glass. However, the bus electrode floated in the insulating layer of the low melting point lead glass, and the conduction between the transparent electrode and the bus electrode was not lost. Therefore, it is possible to eliminate the difficult process of making a small hole in the transparent electrode and to easily obtain a high-definition display.

[Brief description of drawings]

FIG. 1 is a sectional view of an essential part of an embodiment of the present invention.

FIG. 2 is a cross-sectional view of a main part of an example of a conventional reflective AC surface discharge type plasma display panel.

[Explanation of symbols]

 1 Front Substrate 2 Bus Electrode 3 Transparent Electrode 4 Insulating Layer 5 Protective Layer 6 Black Partition 7 White Partition 9 Insulating Layer 10 Data Electrode 11 Rear Substrate

Claims (1)

[Claims] 1. A metal bus electrode is formed on a glass substrate,
A display element having at least a structure in which the metal bus electrode is covered with a transparent electrode, and the transparent electrode is further covered with an insulating layer made of a thick glass film.