KR100587273B1 - Anisotropical Glass Etching Method and Fabricating Method for Barrier Rib of Flat Panel Display Using the same - Google Patents

Abstract

The present invention relates to a method of anisotropic etching of glass.

An anisotropic etching method of glass according to the present invention comprises the steps of forming a mask pattern on a glass substrate, applying a etching solution while maintaining the portion to be etched by the ultraviolet rays in a high energy state, and removing the mask pattern It includes. When such an etching method is used to manufacture partition walls of flat panel displays, high-definition partition walls with large aspect ratios can be easily manufactured.

Description

Glass Anisotropic Etching Method and Fabrication Method of Barrier Panel Using the Same {Anisotropical Glass Etching Method and Fabricating Method for Barrier Rib of Flat Panel Display Using the same}

1 is a perspective view schematically showing a cell structure of a typical AC driving plasma display panel.

Fig. 2 is a sectional view schematically showing a general plasma address liquid crystal display device.

3A and 3B illustrate a method of manufacturing a partition of a flat panel display device using a conventional isotropic etching method of glass.

4A and 4B illustrate an anisotropic etching method of glass according to an embodiment of the present invention.

5 is a diagram showing ultraviolet absorption characteristics of a glass substrate in anisotropic etching of glass.

6A and 6B illustrate an anisotropic etching method of glass according to another embodiment of the present invention.

<Description of Symbols for Main Parts of Drawings>

20,60: upper glass substrate 22,62: lower glass substrate

24 dielectric thick film 26 transparent electrode (ITO electrode)

28: address electrode 30: bus electrode

32, 76: partition 34: dielectric layer

36: protective film 38: phosphor

40,104,124,144: discharge area 50: liquid crystal part

52: plasma channel portion 54: back light

64,74 polarization filter 66 dielectric glass thin film

68 liquid crystal layer 70 transparent electrode

72: color filter 78: anode

80: cathode 82: pixel cell

100,120,140 Glass substrate 102,122,142 Mask pattern

BACKGROUND OF THE INVENTION Field of the Invention The present invention relates to a method of etching glass, and more particularly, to an anisotropic etching method of glass for producing a high-definition microstructure. The present invention also relates to a partition wall manufacturing method for manufacturing a high-definition partition wall in a flat panel display device using an anisotropic etching method of glass.

Cathode ray tube (CRT), which has been the dominant display device means, has a disadvantage in that it is difficult to realize a high definition large screen due to excessive volume and weight. In order to solve these problems, research and development of flat panel displays (hereinafter referred to as "FPDs") that are thin, light, and have high definition image quality have been actively conducted. In particular, a plasma display panel (hereinafter referred to as "PDP") and a plasma address liquid crystal display (Plasma Address) capable of solving a problem caused by a viewing angle or luminance of a liquid crystal display (LCD) device and implementing a large screen among FPDs. There is a growing interest in Liquid Crystal Display (hereinafter referred to as "PALC").

The PDP is a display device in which ultraviolet light generated by gas discharge acts on a phosphor to generate visible light from the phosphor. The PDP is composed of pixel cells divided by partition walls and arranged in a matrix.

1 is a diagram showing a cell structure of a typical AC PDP. Referring to FIG. 1, a PDP includes an upper glass substrate 20 and a lower glass substrate 22, a pair of transparent electrodes 26 arranged on the upper glass substrate 20 in parallel with each other, and a transparent electrode. (26) a pair of bus electrodes 30 arranged parallel to the bottom surface, a dielectric layer 34 covering the pair of transparent electrodes 26 and a pair of bus electrodes 30, and an MgO protective film coated on the bottom of the dielectric layer 34 ( 36 and the address electrodes 28 arranged in a line on the surface of the lower glass substrate 22 opposite to the upper glass substrate 20 so as to vertically cross the transparent electrode 26 and the bus electrode 30; The dielectric thick film 24 covering the address electrode 28, the partition 32 formed vertically on the lower glass substrate 22, and the phosphor applied on the surfaces of the dielectric thick film 24 and the partition wall 32. (38) and a discharge region (40) formed surrounded by the upper glass substrate (20), the lower glass substrate (22), and the partition wall (32).

Briefly describing the light emission process, wall charges are accumulated in the dielectric layer 34 by the address discharge between the bus electrode 30 and the address electrode 28. Dielectric layer 34 and thick dielectric film 24 have a function of protecting the electrodes during discharge. Then, in the discharge region 40 filled with the mixed gas of He + Xe or Ne + Xe, the surface discharge between the bus electrodes 30 occurs and ultraviolet rays are emitted. The MgO passivation layer 34 increases the emission efficiency of secondary electrons during discharge and extends the life of the pixel cell. The emitted ultraviolet rays excite the phosphor 38 to generate visible light of any one of red, green, and blue.

The partition 32 is generally made of glass-ceramics material and is designed to be approximately 100 μm wide and 200 μm high. The partition wall 32 is required to have a high-definition structure having a large aspect ratio (a ratio of height to width) in order to obtain a satisfactory aperture ratio. In particular, when the PDP has a high-definition partition wall, the phosphor coating area and the discharge space are increased accordingly, thereby improving the discharge efficiency and luminance.

PALC is a display device that blocks or transmits white light through a liquid crystal layer controlled by gas discharge, and transmits white light through a color filter to implement various colors. PALC is also composed of pixel cells arranged in a matrix separated by partitions.

Referring to FIG. 2, the cell structure of the PALC is largely composed of the plasma channel unit 52, the liquid crystal unit 50, and the back light 54. The plasma channel portion 52 includes a lower glass substrate 62, a polarization filter 64 bonded to a bottom surface of the lower glass substrate 62, an anode 78 formed side by side on an upper surface of the lower glass substrate 62, and Dielectric glass bonded to the partition wall 76 vertically formed on the lower glass substrate 62 with the cathode 80, the pair of anodes 78 and the cathode 80 interposed therebetween. A thin film 66 is provided. The liquid crystal unit 50 includes a top glass substrate 60, a polarizing filter 74 bonded on the top glass substrate 60, and a red, green, and blue color filter bonded to the bottom surface of the top glass substrate 60. 72, a transparent electrode 70 formed on the bottom surface of the color filter 72, and a liquid crystal layer 68 formed between the transparent electrode 70 and the dielectric glass thin film 66. Backlight 54 is a light source that emits white light.

In the visible light emission process, when a high voltage is applied between the anode 78 and the cathode 80, plasma discharge occurs to address the pixel cell 82 to be displayed. Each pixel cell 82 is divided by a partition wall 76. At this time, as the discharge gas is ionized in the discharge space by the plasma discharge, charged particles are generated, and the anode 78 and the dielectric glass thin film 66 are electrically shorted to each other. Accordingly, in the liquid crystal unit 50, the liquid crystal of the liquid crystal layer 68 is rotated by the voltage difference between the anode 78 and the transparent electrode 70 to which the data signal is applied, and is generated from the backlight 54 to generate the polarization filter ( 64) and white light passing through the lower glass substrate 62 is blocked or transmitted. The white light transmitted is emitted as red, green, and blue light through the color filter 72 and the polarization filter 74.

In FPDs such as PDPs and PALCs, the formation of barrier ribs that separate pixel cells occupies an important weight to determine the performance of the device. One of the manufacturing methods conventionally used in the manufacture of such a partition is the manufacturing method of the partition using the isotropic etching of glass. 3A to 3B are diagrams illustrating a method for producing partition walls using isotropic etching of glass. Referring to FIG. 3A, first, a metal mask pattern 102 is formed on a glass substrate 100 by photolithography. Then, when the etching liquid is reacted through the exposed portion where the mask pattern 102 is not formed, the exposed portion is etched as shown in FIG. 3B to form the discharge region 104. After the etching process, the mask pattern 102 is removed and an electrode material is formed by using a photolithography process.

One of the main problems of this etching method is that during the etching process, as shown in FIG. 3B, the etching lengths in all directions are almost the same isotropic etching, so that they are etched equally to the side by the etching depth. That is, since the etching length is limited in the lateral direction, etching of a sufficient depth in the bottom surface of the glass becomes impossible, and as shown in FIG. 3B, the space occupied by the actual partition wall increases. Thus, the barrier rib formation method using isotropic etching has a problem in that the discharge space of the pixel cell is narrow and the formation of the high-definition barrier rib is difficult. In addition, when the barrier ribs are manufactured by using an isotropic etching method in PALC, the thickness of the lower glass substrate becomes thick, thereby causing a problem of lowering the light transmittance of white light.

As another method of manufacturing the partition wall, a screen print method, a sand blast method, a mold method, and the like have been proposed, but many problems have been pointed out in the respective methods. In the screen printing method, the printing and drying process is performed several times to make a structure having a required height, and then fired to form a partition wall. This manufacturing method takes a lot of manufacturing time due to the repetition of the process, it is difficult to form a high-definition partition wall having a large aspect ratio due to the position of the screen and the substrate is shifted under the repeated operation. In the sandblasting method, a partition wall material is formed to a desired thickness, and then a photosensitive resin pattern is formed thereon to remove unnecessary portions by the sandblasting method to form partition walls. This manufacturing method is not only a waste of the material removed by the abrasive (sand particles) and the manufacturing cost is large, but also a physical impact on the glass substrate by the abrasive has a problem that causes damage to the substrate. In the mold method, the partition wall material is formed and then stamped with a mold to form the partition wall. In the mold method, it is difficult to control the pressure between the mold and the semisolidified partition film or the partition wall paste, and the separation between the mold and the partition wall is difficult, which makes it difficult to manufacture high-definition partition walls. All of the barrier rib manufacturing methods have problems of process complexity, precise process control, etc., and thus are not established as preferable mass production processes.

Accordingly, it is an object of the present invention to provide a method for anisotropic etching of glass for producing high-definition microstructures.

Another object of the present invention is to provide a barrier rib manufacturing method for producing a high-definition barrier rib in FPD.

In order to achieve the above object, the glass etching method of the present invention comprises the steps of forming a mask pattern on a glass substrate, exposing the glass substrate and simultaneously etching the exposed portion by applying an etchant, and removing the mask pattern. It includes a step.

In order to achieve the above object, in the method of manufacturing a partition wall of the flat panel display device of the present invention, a mask pattern is formed on a glass substrate, the glass substrate is exposed, and an etching solution is added to accelerate the etching rate of the exposed portion. Deepening a region and forming a partition wall high, and removing the mask pattern.

Other objects and features of the present invention in addition to the above object 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 4B and 6A to 6B.

4A to 4B are diagrams illustrating an anisotropic etching method of glass according to an embodiment of the present invention. Referring to FIG. 4A, a metal mask pattern 122 is formed on the glass substrate 120 by a photolithography process. As the material of the glass substrate 120, soft glass containing soda lime glass or PbO is used. These glasses have the property of absorbing significant amounts of ultraviolet or other short wavelength (320 nm or less) light, as shown in FIG. As the mask pattern 122, a Cr thin film layer is mainly used, and other suitable metals, inorganic materials, organic materials, and the like may be selected and used. Next, the etching solution is sprayed onto the substrate on which the mask pattern 122 is formed while irradiating ultraviolet rays. As a light source for generating ultraviolet rays, an ultraviolet ray generating lamp having an appropriate wavelength may be used depending on the type of mercury lamp, mercury xenon lamp, and glass substrate 120. The portion of the glass substrate 120 exposed to ultraviolet rays is in a high energy state by ultraviolet energy by absorbing ultraviolet rays. The portion that absorbs ultraviolet rays is in a higher energy state than the portion that is masked by the mask pattern 122, so that the etching rate of the portion absorbing the ultraviolet rays is faster. Thus, as shown in FIG. 4B, an anisotropic etching is performed because the etching rate in the depth direction is faster than the etching rate in the horizontal direction toward the portion covered by the mask pattern 122. The mask pattern 122 formed on one or both surfaces of the glass substrate 120 protects a portion where the microstructure is to be formed during etching.

Meanwhile, the etching in the present invention may use a glass etching method of dipping. In addition, the etching technique applied in the present invention is to apply a conventional spray or dipping technique, the change in the degree of etching according to the relationship or degree of absorption of the kind or amount thereof is not particularly limited in the present invention, all conventional I can understand.
6a to 6b are views showing a method for etching the glass according to another embodiment of the present invention. Referring to FIG. 6A, first, metal mask patterns 142 are formed on both surfaces of the upper and lower surfaces of the glass substrate 140, and ultraviolet rays are irradiated on opposite surfaces of the surface to be etched. At this time, the etching solution is brought into contact with the surface to be etched, as shown in FIG. 6B, to perform etching. The ultraviolet ray is then absorbed into the glass substrate 140 appropriately without being absorbed by the etching liquid. The portion that absorbs ultraviolet rays without being masked by the mask pattern 142 has a high etching rate during etching, and thus anisotropic etching to the deep portion of the glass substrate 140 is possible. After the etching is completed by the process of FIG. 4B or 6B, the mask patterns 122 and 142 are removed and a structure vertically formed on the glass substrates 120 and 140 is completed.

In the fabrication of barrier ribs of a flat panel display using anisotropic etching of glass as shown in FIG. 4B or 6B, etching is not etched in the same length in all directions during etching, but rather in the depth direction of the glass rather than in the direction where the barrier ribs are to be formed. This is done quickly. Therefore, a high-definition partition wall having a large aspect ratio is formed, and the discharge area 124 and 144 can be widened by reducing the space occupied by the partition wall unnecessarily. In addition, the glass substrate thickness below the discharge region formed by etching can be reduced to a minimum.

In the case of PDP, after forming an electrode material by a general sputtering method or other appropriate method, it is formed into a pattern by the photolithography process. Applying the dielectric layer and the phosphor on this again makes a bottom plate having vertically formed partition walls. In the case of PALC, a discharge cell can be formed by removing a mask pattern, forming a metal pattern on the etched portion of the glass substrate, and then bonding a thin film of dielectric glass.

As described above, the anisotropic etching method of the glass according to the present invention has an advantage that can easily manufacture a high-definition microstructure having a large aspect ratio compared to the conventional isotropic etching method. As a result, unnecessary space occupied by the partition wall can be reduced, thereby increasing the discharge area, thereby improving the discharge efficiency of the FPD. In the case of PALC, since the thickness of the lower glass substrate under the discharge region can be minimized, the light transmittance of the white light can be improved.
Moreover, etching of sufficient depth is possible in the bottom surface direction of the glass, and it has the effect of significantly shortening an etching time or a manufacturing time.

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 (9)

a) forming a mask pattern on the glass substrate, b) exposing the glass substrate and etching by spraying an etching solution on an opposite surface on which the mask pattern is formed; c) removing the mask pattern on the glass substrate on which the etching is completed. The method of claim 1, In the step a), further forming another mask pattern on the etched surface of the glass substrate. The method according to claim 1 or 2, In the step b), etching is performed by applying an etchant to the surface being etched while irradiating ultraviolet rays to the surface on which the mask pattern is formed. The method of claim 1, B) etching the glass substrate by dipping. The method of claim 1, In the step a), the mask pattern including the chromium (Cr) thin film as a material is formed on the portion where the structure of the glass substrate is to be formed. The method of claim 1, The glass substrate is an etching method of glass, characterized in that any one of soda lime glass or soft glass. The method of claim 1, The glass substrate is any one of the glass or the glass which is coated and then baked in the form of a paste, the etching method of glass. A partition wall manufacturing method for a flat panel display device comprising forming a partition wall by using the glass anisotropic etching method of claim 1. delete

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