KR20040081496A - Method for forming electrode of plasma display panel - Google Patents

Abstract

PURPOSE: A method is provided to allow for ease of control of line width of electrode and obtain an electrode pattern of high resolution. CONSTITUTION: A method comprises a step of forming a black layer(340) on a transparent substrate(320) by printing a black photosensitive paste; a step of patterning the black layer by radiating light to the front surface of the substrate through the use of a photo mask and developing the resultant structure; a step of forming a white layer(360) by printing a white photosensitive paste on the front surface of the substrate where the pattern of the black layer is formed; a step of forming a pattern of the white layer on the pattern of the black layer by radiating light to the rear surface of the substrate without using a photo mask and developing the resultant structure; and a step of baking patterns of the black layer and the white layer.

Description

Electrode formation method of plasma display panel {METHOD FOR FORMING ELECTRODE OF PLASMA DISPLAY PANEL}

The present invention relates to an electrode forming method of a plasma display panel (PDP), and more particularly to a method of patterning an electrode having a structure in which a black layer for contrast enhancement and a white layer for luminance enhancement are stacked. will be.

In general, a plasma display panel injects and discharges a discharge gas between two substrates coated with a plurality of electrodes, and then discharges each discharge cell by applying a voltage pulse to the electrodes, thereby addressing the intersection of the two electrodes. An image display device for implementing characters or graphics.

1A and 1B are perspective views of a conventional three-electrode surface discharge type plasma display panel, through which a manufacturing process of the plasma display panel is schematically described as follows.

The front substrate 110 is provided, and a plurality of X-electrodes and Y-electrodes are formed on the front substrate. The X-electrode and the Y-electrode are composed of a transparent electrode 114 and a bus electrode 112, respectively, and a pair of X-electrodes and Y-electrodes are provided per unit discharge cell. A dielectric layer 116 is then formed to bury the X- and Y-electrodes. A protective film 118 such as, for example, an MgO film is formed on the dielectric layer.

Meanwhile, in the case of the rear panel facing the front panel, the address electrode 104 is formed on the rear substrate 102. The address electrode is embedded by the dielectric layer 106, and the partition 108 is formed on the dielectric layer in parallel with the address electrode, and the phosphor layer 120a of red, green, and blue (R, G, B) is formed inside the partition. , 120b, 120c are applied.

As described above, the completed front panel and the rear panel are sealed to each other in an aligned state, and exhaust is performed under vacuum to remove impurities such as moisture remaining in the sealed substrate. Next, a mixed gas such as Ne, Xe, He, etc. is sealed in accordance with the required characteristics of the panel, and the panel is separated from the exhaust device. Subsequently, a predetermined voltage is applied to the panel to cause aging and discharge, and a driving chip is mounted to complete the plasma display panel.

An image display process of the plasma display panel configured as described above is as follows.

When the discharge start voltage of 150 V to 300 V is supplied to the sustain electrode (X-electrode or Y-electrode) and the address electrode of an arbitrary discharge cell, wall charges are formed on the inner surface of the corresponding discharge space, and then to the sustain electrode and the address electrode. When the address discharge voltage is supplied, address discharge occurs between the sustain electrode and the address electrode.

The electric field is generated inside the cell by the address discharge, and the trace electrons in the discharge gas are accelerated, the accelerated electrons and the neutral particles in the gas collide with each other, and are ionized into electrons and ions. Neutral particles are gradually ionized into electrons and ions at high velocity due to another collision, and the discharge gas is converted into a plasma state, and vacuum ultraviolet (UV) is generated, and the ultraviolet rays excite the phosphor to generate visible light. Light emission, that is, image display can be recognized.

Subsequently, when a sustain discharge voltage of 150 V or more is supplied to the sustain electrodes (X-electrode and Y-electrode), sustain discharge occurs between sustain electrodes in the corresponding discharge cell so that light emission of the cell is maintained for a predetermined time.

Here, since the sustain electrode is applied with a voltage for address discharge and sustain discharge, the higher the electrical conductivity is, the better the electrical conductivity is, but since it is located on the path through which visible light passes, it should be formed in consideration of the light transmittance to improve luminance.

Therefore, the sustain electrode is formed of a transparent ITO material to improve light transmittance, which is commonly referred to as a transparent electrode.

However, since ITO transparent electrode is transparent, it improves brightness but has low electrical conductivity. When a high-resolution, large-size plasma display panel is manufactured, a voltage drop occurs between the first part and the last part where voltage is applied to display a desired signal. In order to compensate for this, a metal electrode having excellent electrical conductivity, that is, a bus electrode, is formed on the upper surface of the transparent electrode. As a result, the improvement of luminance by the ITO transparent electrode and the prevention of voltage drop by the opaque bus electrode were simultaneously implemented.

Recently, a technique for forming a sustain electrode using only a trapezoidal bus electrode without a transparent electrode has been reported.

On the other hand, since the bus electrode is made of an opaque metallic material, the overall brightness may be reduced by blocking the light displayed in the discharge space, so the bus electrode should be formed with the minimum width.

The conventional bus electrode forming method will be described.

As the most common bus electrode, a triple structure bus electrode of Cr-Cu-Cr is used, but the bus electrode of such structure requires etching each layer separately, and the etching process is complicated. Cause the quality of the product. In addition, the thickness of Cr-Cu-Cr film needs to be thick to secure excellent electrical conductivity even at the fine electrode width to cope with high definition HDTV. Therefore, it takes a long time to deposit by sputtering and also degrades the film quality. In order to improve the use of a single metal through thick film printing.

The most widely known single metals are aluminum (Al) and silver (Ag), which are inexpensive but have lower electrical conductivity than silver. Recently, silver is mainly used as a bus electrode.

2A to 2C show a prior art process of forming a bus electrode by the photo method (also called the Podel method) using a photosensitive silver (Ag) paste.

First, as shown in FIG. 2A, a black silver paste is printed on the substrate 220 to form a black layer 240, and a white silver paste is printed on the black layer 240 to print the white layer 260. The black layer 240 is for improving the contrast characteristic, and the white layer 260 is for improving the luminance characteristic.

Subsequently, as shown in FIG. 2B, the photomask 280 is aligned on the white layer 260 and exposed to ultraviolet light on the white layer. Then, the electrode pattern is formed as shown in FIG. 2C to stack the black layer / white layer. Will form. In this state, when the organic binder component is decomposed by firing at a predetermined high temperature, a bus electrode having a total thickness of about 5 μm is completed.

However, since the black layer 240 is positioned below the white layer 260 in the above-described conventional technology, the exposure source (ultraviolet ray) does not sufficiently reach at the time of exposure and thus is not sufficiently exposed. In this state, the development is performed according to the degree of covering of the white layer 260, and the black layer 240 is patterned.

Therefore, the above-described prior art is difficult to control the line width of the electrode, there is a problem in forming the electrode with a desired high-definition line width.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described problems, and an object thereof is to provide an electrode forming method of a plasma display panel suitable for forming an electrode with a desired high-definition line width by easily adjusting the line width of the electrode.

1A and 1B are perspective views of a conventional surface discharge plasma display panel,

2A through 2C are cross-sectional views illustrating a method of forming an electrode of a plasma display panel according to the related art;

3A to 3F are cross-sectional views illustrating a method of forming an electrode of a plasma display panel according to an exemplary embodiment of the present invention.

※ Explanation of code for main part of drawing

320: substrate 340: black layer

360: white layer 380: photomask

The electrode forming method of the plasma display panel according to the present invention for achieving the above object comprises the steps of printing a black photosensitive paste for the electrode on a transparent substrate to form a black layer; Irradiating, developing and patterning the black layer on an entire surface of the substrate using a photomask; Forming a white layer by printing a white photosensitive paste for an electrode on a front surface of the substrate on which the black layer pattern is formed; Irradiating and developing an exposure source on the back surface of the substrate without a photomask to form a pattern of the white layer on the pattern of the black layer; And firing the black layer and the white layer pattern.

Preferably, the paste of the white layer in the present invention is characterized in that the positive type photosensitive paste in which the portion irradiated with the exposure source is removed during development.

Preferably, the black layer paste and the white layer paste are each silver (Ag) paste.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art may more easily practice the present invention.

3A to 3F are cross-sectional views illustrating a method of forming an electrode of a plasma display panel according to an exemplary embodiment of the present invention.

First, as shown in FIG. 3A, a black silver paste is printed and dried on the transparent glass substrate 320 front surface to form a black layer 340. If necessary, printing and drying of the paste can be repeated several times. Drying is carried out at a temperature of about 80 ° C. for about 20 minutes.

The paste of the black layer 340 is a negative type photosensitive paste, and a portion irradiated with ultraviolet rays remains without melting during development to form a pattern.

Subsequently, as illustrated in FIG. 3B, the photomask 380 is aligned on the front side of the substrate on which the black layer 340 is formed, and then the black layer 340 is exposed by irradiating ultraviolet (UV) light. In this case, since the black layer 340 is not covered with the white layer, the black layer 340 is directly exposed to an exposure source, thereby providing sufficient exposure.

Subsequently, the black layer 340 is patterned by developing as shown in FIG. 3C, and then a white silver paste is printed on the entire surface of the substrate on which the black layer 340 pattern is formed to form the white layer 360. If necessary, the printing and drying of the paste may be repeated several times, and the drying may be performed at a temperature of about 80 ° C. for about 20 minutes.

The white layer 360 is a positive type photosensitive paste, which is the type opposite to the black layer. The white layer 360 is then dissolved and removed during development.

Subsequently, exposure is performed without a photomask on the rear surface of the substrate 320 as shown in FIG. 3D. As a result, since the black layer 340 pattern serves as an exposure mask, the portion overlapped with the black layer 340 pattern is not irradiated with ultraviolet rays.

As a result, when the development is performed as shown in FIG. 3E, an electrode pattern in which the black layer 340 and the white layer 360 are stacked may be obtained.

3F is a state of firing at 450 to 600 ° C. for 5 to 6 hours.

The above-described embodiment is an embodiment of forming a bus electrode without an ITO transparent electrode on a front substrate, and the technical idea of the present invention is to form a bus electrode on an ITO transparent electrode when an ITO transparent electrode is formed on a front substrate. The present invention can be applied to the present invention, and the technical idea of the present invention can be applied when the address electrode is formed on the rear substrate.

As such, although the technical idea of the present invention has been described in detail according to the above-described preferred embodiment, it should be noted that the above-described embodiment is for the purpose of description and not of limitation. In addition, those skilled in the art will understand that various embodiments are possible within the scope of the technical idea of the present invention.

The electrode forming method of the present invention has the effect that the line width of the electrode can be easily adjusted to obtain a desired high-definition electrode pattern.

Claims (5)

Printing a black photosensitive paste for an electrode on a transparent substrate to form a black layer; Irradiating and developing an exposure source on a front surface of the substrate using a photomask to pattern the black layer; Forming a white layer by printing a white photosensitive paste for an electrode on a front surface of the substrate on which the black layer pattern is formed; Irradiating and developing an exposure source on the back surface of the substrate without a photomask to form a pattern of the white layer on the pattern of the black layer; And Firing the black and white layer patterns Electrode formation method of a plasma display panel comprising a. The method of claim 1, The paste of the white layer is a positive type photosensitive paste in which a portion irradiated with an exposure source is removed during development. The method of claim 1, The paste of the black layer and the paste of the white layer are silver (Ag) pastes, respectively. The method according to any one of claims 1 to 3, And the electrode is a bus electrode of a front panel. The method according to any one of claims 1 to 3, And the electrode is an address electrode of a rear panel.