KR100260233B1 - Method for producing spacer for fpd using screen print method - Google Patents

Abstract

PURPOSE: A method of forming a spacer for flat display using a printing method is provided to laminate a spacer by using a mask having pattern holes of different sizes. CONSTITUTION: The first spacer(3a) is formed by laminating a spacer until a height of a spacer corresponds to 3/4 of a thickness of a print mask for the first spacer. A firing process and a hardening process for the first spacer(3a) are performed. The second spacer(3b) is formed on the first spacer(3a) by using a print mask for the second spacer. A size of the print mask for the second spacer is less than a size of a pattern hole of a print mask for the first spacer. The firing process and the hardening process for the second spacer(3b) are performed. The laminating process, the firing process, and the hardening process is performed repeatedly.

Description

Spacer Formation Method for Flat Panel Display Using Printing Method

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a spacer for flat panel displays using a printing method, and more particularly, to a manufacturing method in which a spacer is laminated using a mask having a different size of a pattern hole.

Recently, with the rapid development of ultra-high-density semiconductor manufacturing technology and ultra-high vacuum technology, research on new micron-sized triode tube devices has been vigorous. New flat-panel displays having only the advantages of CRT and LCD are applied to such displays. Pay attention to develop.

A field emission display device is a flat panel display, which consists of a tip- or wedge-type cathode that emits electrons and an anode coated with a planar body, induces electron emission from a plurality of micro tips, and the phosphor is stimulated to generate the outermost electron of the phosphor. The light is generated in the process of being excited and transitioned to display a desired image display. In other words, when the field emission display device applies a high electric field (about 5 × 10 ⁷ V / cm) to a metal or conductor in a vacuum, electrons pop out from the solid through quantum mechanical tunneling. It is a display element which displays an image by accelerating by a magnetic field by a voltage applied to an electrode and hitting the fluorescent layer formed on the electrode to emit light.

In addition, the field emission display device as described above includes a top plate on which a fluorescent layer and a transparent electrode are formed, and a bottom plate on which a cathode array and a gate electrode are formed, and a spacer for maintaining a constant gap therebetween.

The spacer is formed to prevent the substrate from being broken or warped due to compressive stress during high vacuum of the field emission display device, and typically includes a top plate on which a transparent electrode and a fluorescent layer are formed, a bottom plate on which a cathode array and a gate electrode are formed. It is a structure that serves to maintain at intervals of 100 to 300 micrometers.

In a flat panel display such as a field emission display device, the possible distance between the top plate and the bottom plate is in the range of 150 to 2000 μm, but for the panel having high brightness and high luminous efficiency, the distance is as large as possible, that is, around 2000 μm. Spacers are typically formed to prevent the substrate from breaking or flexing due to compressive stress at high vacuum of the device.

However, manufacturing such that the height of the spacer for the field emission display device is about 2000 mu m involves many difficult problems. Various spacer formation methods have been proposed to solve this problem. In the conventional method of forming a spacer, a photolithography method for uniformly applying and patterning a spacer material between a cathode array and a lower plate on which a gate electrode is formed, a method of dispersing fine particles for spacers on a substrate, There is a method of manufacturing a spacer in a separate process without directly forming the spacer and arranging the spacer on a lower plate on which a cathode array and a gate electrode are formed, and a printing method.

However, the above-mentioned methods each have a big problem. Photolithography has great advantages in manufacturing fine spacers, but the process of forming a photoresist film on the material formed of the spacer material to pattern the spacer material and removing the remaining photoresist pattern is complicated and difficult to select materials. In the case of dispersing the fine particles for the spacer on the substrate, it is difficult to manufacture a high-density panel, and if scattered over the entire panel, the cathode tips may be damaged, and when the spacer is manufactured and arranged in a separate process, the spacer may be accurately It is difficult to align and fix in position, and the printing method is very useful because it can be used by applying the partition forming method used in the conventional PDP, but it is difficult to form a spacer having a high height (300 μm) with a narrow width.

In addition, the conventional printing method will be described in more detail because, after the spacer is formed by the thickness of the mask, the conventional printing method is more likely to be separated together with the mask when the spacer formed in the next printing is inserted into the mask hole and separated from the substrate. As a result, it is difficult to form a thickness greater than a printing mask in forming a dot or line spacer. Also, as lamination printing is continuously executed, the gap between the mask and the upper end of the printed surface is changed, so that the printing pressure is changed accordingly, and the existing printed portion is slightly inserted in the mask opening, so that the accumulation printing is performed once per lamination printing. The printed thickness tends to decrease gradually.

The present invention for solving the above problems is to provide a more improved printing method, that is, a manufacturing method for laminating a spacer using a mask having a different size of the pattern hole.

1A is a top view of a substrate with spacers formed in accordance with one embodiment of the present invention.

1B is a perspective view of the substrate on which the spacer of FIG. 1A is formed.

FIG. 2 is an enlarged view of a spacer formed on the substrate of FIG. 1B; FIG.

3A is a top view of a substrate with spacers formed in accordance with another embodiment of the present invention.

3B is a perspective view of the substrate on which the spacer of FIG. 3A is formed.

4 is an enlarged view illustrating a spacer formed on the substrate of FIG. 3B;

* Description of the symbols for the main parts of the drawings *

1: substrate

3: dot type spacer

3a: dot type first spacer

3b: dot-shaped second spacer

3c: dot type third spacer

5: line type spacer

5a: line-type first spacer

5b: second linear spacer

5c: Line 3rd spacer

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

According to one embodiment according to the invention of Figs. 1A to 1B, when the shape of the spacer 3 to be formed by the printing method is a dot, the spacer forming method by the printing method has a height of the spacer 3 first. Lamination printing to form a first spacer 3a (shown in FIG. 2) until it becomes about 3/4 of the thickness of the printing mask for the spacer, firing and curing the first spacer 3a, and 1, by repeating the laminated printing by using the second spacer printing mask made smaller than the pattern hole size of the spacer printing mask to form the second spacer 3b (shown in FIG. 2), the second spacer (3b) is fired and hardened, and the size of the pattern hole is gradually reduced to repeat the above steps, i.e., the printing, firing and curing steps, to form a spacer 3 having a desired height. According to one embodiment of the invention, the height of the spacers stacks only about three quarters of the print mask, which is a problem in the prior art, i.e. when the mask is removed after the printing process is completed, the spacer is removed together with the mask or The nonuniformity of thickness can be prevented from occurring, and printing can be continued without the above-mentioned problem, and manufacture of the spacer 3 of desired height is attained.

For example, in the case of having a thickness of about 120 μm, the first spacer 3a having a height of about 90 μm, which is 3/4 of the mask thickness, is formed by printing, firing, and curing with the printing mask for the first spacer. In the next step, the second spacer printing mask having a smaller pattern hole than the first spacer printing mask is printed, fired, and cured, and laminated printing is performed using the laminated printing mask, thereby forming the upper portion of the upper portion of the first spacer 3a. A 90 micrometers second spacer 3b is formed. The printing mask for the spacer may be prepared with a plurality of different masks, and the mask used in each step may proceed in more steps in order of decreasing size of the pattern hole. In the same manner as described above, the steps are repeated until the spacers 2 of reasonable heights are formed, and lamination printing is performed.

The method according to an embodiment of the present invention makes it possible to stack a dot-shaped spacer much higher than the conventional one.

Incidentally, the above-described spacer printing mask is used for the first, second, third ... It can be a plurality of masks, the size of the pattern hole tends to decrease sequentially, and is used sequentially as the step proceeds.

The size of the pattern hole of the printing mask for the first spacer used at the start of printing is properly designed in consideration of the number of spacers according to the height of the desired spacer and the internal pressure of the panel. Since the size of the pattern hole of the printing mask for the second spacer is not only smaller in diameter than the size of the pattern hole of the printing mask for the first spacer, the degree can be set appropriately by those skilled in the art. It is omitted in the present detailed description. The above-mentioned masks may all have the same thickness. In such a case, as the printing proceeds, the gap between the spacer formed by printing a plurality of times and the mask may be gradually reduced, which may result in deterioration of the printing characteristics. It is possible to fit other masks (e.g. made of polyester) with a predetermined thickness in the spacing to prevent spacing therefrom and to prevent the resulting pressure change due to the progression of the above-described steps.

It is preferable to further include a polyester under the SUS plate in order to improve the printing property, so that the printing mask for the spacer is used as the SUS plate rather than the SUS mesh to provide excellent printing characteristics and provide restoring force.

According to an embodiment of the present invention, the height of the spacer can be made reasonably high, and the width can be narrowed to enable the manufacture of a high-density display device and to increase the space between panels. Since high voltage can be applied, it has the feature to manufacture high brightness and high efficiency panel.

According to another embodiment according to the invention of Figs. 2A to 2B, when the shape of the spacer 5 to be formed by the printing method is a line type, the spacer forming method by the printing method has a height of the spacer 5 first. Lamination printing to form a first spacer 5a (shown in FIG. 3) until it becomes about 3/4 of the thickness of the printing mask for the spacer; firing and curing the first spacer 5a; 1, the laminated printing is again performed using the second spacer printing mask, which has a smaller pattern hole size of the spacer printing mask, to form a second spacer 5b (shown in FIG. 3), the second spacer (5b) is fired and hardened, and the size of the pattern hole is gradually reduced to repeat the above steps, i.e., the printing, firing and hardening steps, thereby forming a spacer 5 having a desired height. . According to one embodiment of the invention, the height of the spacers stacks only about three quarters of the print mask, which is a problem in the prior art, i.e. when the mask is removed after the printing process is completed, the spacer is removed together with the mask or The nonuniformity of thickness can be prevented from occurring, printing can be continued without the above-mentioned problem, and the spacer 5 of desired height can be manufactured.

For example, in the case of having a thickness of about 120 μm, the first spacer 5a having a height of about 90 μm, which is 3/4 of the thickness of the mask, is first formed by printing, firing, and curing with a printing mask for the first spacer. In the next step, the second spacer printing mask having a smaller pattern hole than the first spacer printing mask is printed, fired, and cured, and laminated printing is performed using the laminated printing mask, thereby forming the upper portion of the first spacer 5a. A 90 micrometers second spacer 5b is formed. The printing mask for the spacer may be prepared with a plurality of different masks, and the mask used in each step may proceed in more steps in order of decreasing size of the pattern hole. In the same manner as described above, the steps are repeated until the spacers 5 of reasonable height are obtained, and the laminated printing is performed.

The method according to another embodiment of the present invention makes it possible to laminate print a line-shaped spacer much higher than conventionally.

Incidentally, the above-described spacer printing mask is used for the first, second, third ... It can be a plurality of masks, the size of the pattern hole tends to decrease sequentially, and is used sequentially as the step proceeds.

The size of the first spacer pattern hole used at the start of printing is appropriately designed in consideration of the number of spacers according to the height of the desired spacer and the internal pressure of the panel. The size of the pattern hole of the printing mask for the second spacer is not only smaller on each side than the size of the pattern hole of the printing mask for the first spacer, but the degree can be appropriately set by those skilled in the art. Therefore, the detailed description thereof will be omitted. The above-mentioned masks may all have the same thickness. In such a case, as the printing proceeds, the gap between the spacer formed by printing a plurality of times and the mask may be gradually reduced, which may result in deterioration of the printing characteristics. It is possible to fit other masks (e.g. made of polyester) with a predetermined thickness in the spacing to prevent spacing therefrom and to prevent the resulting pressure change due to the progression of the above-described steps.

It is preferable to further include a polyester under the SUS plate in order to improve the printing property, so that the printing mask for the spacer is used as the SUS plate rather than the SUS mesh to provide excellent printing characteristics and provide restoring force.

Another embodiment according to the present invention can be made to make the height of the spacer reasonably high, and also the width can be narrowed to enable the production of high-density display elements and to increase the distance between panels more than the anode portion Since high voltage can be applied, it has the feature to manufacture high brightness and high efficiency panel.

The dot and line spacers to be printed should generally have an appropriate width in consideration of printing characteristics, and are designed to have a reasonable number since the number is too large when considering the exhaust conductance.

In addition, spacers are designed to form an appropriate number per unit area to withstand external atmospheric pressure.

In the present invention according to the above-described printing, when the continuous printing of the dot- or line-shaped pattern, after the spacer is formed by the thickness of the mask, the printing is performed by inserting the existing spacer formed in the mask pattern hole substrate (1) It is not separated from the mask and can be separated with the mask, and since the height of the spacer can be several times higher, it is possible to apply a higher voltage to the anode to make a panel of high brightness and high luminous efficiency. .

Claims (4)

Forming the first spacer 3a by laminating printing until the height of the spacer is about 3/4 of the thickness of the printing mask for the first spacer, Firing and curing the first spacer 3a, The second spacer 3b is formed on the first spacer 3a by lamination printing using the second spacer printing mask made smaller than the pattern hole size of the first mask for printing the mask. step, Firing and curing the second spacer 3b, and A method of forming a spacer by a printing method comprising selecting one of the plurality of prepared spacer masks in order of decreasing size of the pattern hole and repeating the lamination, firing, and curing steps. The method of claim 1, wherein the thickness of the second spacer is 70 to 80% smaller than the thickness of the mask. The method of claim 1, wherein the spacer is a dot or line. The method of claim 1, wherein the spacer mask is made of SUS material, and further includes a polyester on a lower side of the SUS plate in order to provide a restoring force due to phosphorus pressure during printing.

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