JP2006085123A - Liquid crystal display panel and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a liquid crystal display panel, having high bonding strength between a color filter substrate and a thin-film transistor array substrate, as well as high reliability and display quality, and to provide its manufacturing method. <P>SOLUTION: The liquid crystal display panel is provided with the color filter substrate and the thin-film transistor array substrate, which are disposed parallel to each other and a liquid crystal layer between the substrates. A plurality of spacers are disposed on a black matrix of the color filter substrate. Each spacer abuts against at least one end part of a gate layer line and a source layer line on the thin-film transistor array substrate. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a display panel and a manufacturing method thereof. More particularly, the present invention relates to a highly reliable liquid crystal display panel and a method for manufacturing the same.

  With the rapid development of multimedia systems, image data is mainly transmitted in digital format through a network, not in analog format via a cable. In order to adapt to the lifestyles of modern people, lighter and smaller video display devices or image display devices have also been designed. While conventional cathode ray tubes (CRT) have high display quality and can be produced at a relatively low cost, the electron gun inside the CRT not only generates harmful electromagnetic waves, but also makes the CRT itself bulky. It was.

  Flat panel display devices are forced to develop extremely rapidly due to the recent advancement of optoelectronic manufacturing technology and the maturation of semiconductor manufacturing processes. Liquid crystal displays (LCDs), in particular, have gradually replaced conventional CRTs due to their low operating voltage, irradiation without electromagnetic radiation, light weight, and small volume occupancy, becoming the mainstream of display products.

  A liquid crystal display (LCD) mainly includes a liquid crystal display panel and a backlight module. The liquid crystal display panel further includes a color filter substrate, an active element array substrate, and a liquid crystal layer sandwiched between the two substrates. The backlight module provides a surface light source necessary for the liquid crystal display panel to display an image. After assembling the liquid crystal display panel, a plurality of spacers are often provided between the color filter substrate and the active device array substrate in order to ensure a certain distance between the color filter substrate and the active device array substrate. Is arranged.

  FIG. 1 is a schematic cross-sectional view of the structure of a conventional liquid crystal display panel. As shown in FIG. 1, the liquid crystal display panel 100 mainly includes a color filter substrate 110, a thin film transistor array substrate 120, a liquid crystal layer 130, a sealant 140, and a plurality of spacers 150. The sealant 140 is positioned around the color filter substrate 110 and the thin film transistor array substrate 120 to bond the color filter substrate 110 and the thin film transistor array substrate 120 together. The liquid crystal layer 130 completely fills the space surrounded by the color filter substrate 110, the thin film transistor array substrate 120, and the sealant 140. The spacer 150 is a ball-like element disposed between the color filter substrate 110 and the thin film transistor array substrate 120 so that the two substrates of the color filter substrate 110 and the thin film transistor array substrate 120 are located at a predetermined distance. It is a spacer. However, these ball spacers 150 in the liquid crystal display panel tend to gather in one place when the liquid crystal display panel vibrates. Therefore, even if the electric field of the normal mode exists, the twist of the liquid crystal molecules is reduced in the vicinity of the gathering of the ball spacers 150, leading to the so-called “spacer leakage”.

  Spacer-on-color filter (SOC) technology has been developed to reduce the above-mentioned drawbacks. In this technique, a plurality of spacers made of an organic photosensitive material are formed on a black matrix of a color filter substrate. Accordingly, after the color filter substrate and the thin film transistor array substrate are connected, the spacer is disposed on the scanning line, common line, or data line of the thin film transistor array substrate.

  Here, it should be noted that the size and function of the liquid crystal display panel are in an expanding trend, and that these two will continue to expand in the future. For example, liquid crystal televisions and other wide display devices with attached speakers are quite common. However, if the sealant reaches the age or fatigue limit due to the weight of the large substrate or the acoustic vibration generated by the speaker, or the spacer arrangement becomes uneven, the color filter substrate and the thin film transistor array The substrate may be separated from each other. This often results in abnormal indications and premature failure. These problems can be alleviated by increasing the width of the sealant so that the upper substrate and the lower substrate are more firmly sealed with each other. Often results in inconveniences for manufacturing (coating and curing) and for narrowing the edges of the panel.

  In view of these problems, a method for improving the reliability and increasing the size of a liquid crystal display panel is important in increasing the market share in display products.

  Accordingly, the present invention is directed to a liquid crystal display panel having a thin film transistor array substrate and a color filter substrate. A plurality of spacers are arranged inside the liquid crystal display panel, and the spacers are in contact with the edge of the structure having a step on the surface of the thin film transistor array substrate. This increases the coupling stability between the color filter substrate and the thin film transistor array substrate, thereby improving the reliability and display quality of the liquid crystal display panel.

Furthermore, the present invention is directed to a method for manufacturing a liquid crystal display panel. By changing the distribution of the spacers inside the liquid crystal display panel, the coupling between the color filter substrate and the thin film transistor array substrate is strengthened, and the positioning step between the color filter substrate and the thin film transistor array substrate prior to the coupling step is performed. Simplified. Ultimately, the assembly efficiency of the liquid crystal display panel is increased, and the reliability of the liquid crystal display panel is improved.

  In order to achieve the above and other excellent effects, and according to the purpose of the present invention, the present invention provides a liquid crystal display panel as embodied and outlined herein. The liquid crystal display panel includes a color filter substrate and a thin film transistor array substrate arranged in parallel, a plurality of spacers, and a liquid crystal layer. The thin film transistor array substrate includes a plurality of gate layer lines and a plurality of source layer lines thereon. The spacer is disposed on the color filter substrate and is in contact with at least one edge of the plurality of gate layer lines or the plurality of source layer lines. The liquid crystal layer is disposed in a space between the color filter substrate, the thin film transistor array substrate, and the spacer.

  According to an embodiment of the present invention, the spacer may be disposed in the overlapping region of the gate layer line and the source layer line so that the spacer contacts the gate layer line and the source layer line simultaneously. Further, adjacent spacers attached to the color filter substrate are connected to form a locking structure. The locking structure has a central recess for locking in the overlapping region of the gate layer line and the source layer line.

  According to an embodiment of the present invention, the spacers may be arranged on both sides of the gate layer line or the source layer line so that the spacer contacts the gate layer line or the source layer line. Further, adjacent spacers attached to the color filter substrate are connected to form a locking structure. The locking structure has a central recess for locking to the gate layer line or the source layer line.

  According to one embodiment of the present invention, for example, the gate layer line is a scan line and the source layer line is a data line. In another embodiment of the present invention, for example, the gate layer line is a scan line and a common line, and the source layer line is a data line. For example, the spacer has a cylindrical shape or a wall shape.

  The present invention also provides a method for manufacturing a liquid crystal display panel. First, a thin film transistor array substrate is prepared. The thin film transistor array substrate has a plurality of gate layer lines and a plurality of source layer lines thereon. Thereafter, a color filter substrate is prepared. The color filter substrate has a plurality of spacers thereon. The thin film transistor array substrate and the color filter substrate are positioned in such a manner that a spacer on the color filter substrate contacts at least one edge of the plurality of gate layer lines or the plurality of source layer lines, and Combined.

  In one embodiment of the present invention, a method for forming a color filter substrate includes the following steps. First, a glass substrate is prepared. Thereafter, a black matrix is formed on the glass substrate. The black matrix surrounds several regions in the glass substrate to form a plurality of openings. Next, a color filter unit is formed in the opening. Then, a plurality of spacers are formed on the black matrix. The spacer is formed, for example, by forming an organic photosensitive layer on a glass substrate and patterning the organic photosensitive layer. After the spacer is formed, a post bake operation may be performed.

  As described above, the present invention forms a plurality of cylindrical or wall-shaped spacers by applying the SOC technology to the color filter substrate. After the liquid crystal display panel is assembled, the spacers are arranged in a unique manner so that the spacers abut against the edges of the gate layer lines or source layer lines on the thin film transistor array substrate. Since the spacers make the inside of the liquid crystal display panel strong, it is difficult for the color filter substrate and the thin film transistor array substrate to move from their original positions to other places due to vibrations and other external pressures. Accordingly, the reliability of the liquid crystal display panel is improved, and the time required for positioning the color filter substrate and the thin film transistor array substrate is shortened. In other words, the overall product yield is improved.

  In summary, the present invention has at least the following features and advantages.

  1. After the liquid crystal display panel is assembled, the spacer contacts the structure having a step on the thin film transistor array substrate. This reduces the possibility that the color filter substrate and the thin film transistor array substrate move relative to each other due to vibrations or other external forces. As a result, high bonding strength, high reliability, and high display quality for the assembled liquid crystal display panel are ensured.

  2. Since the spacer is formed in the black matrix of the color filter substrate, the aperture ratio and the transparency of the liquid crystal display panel can be maintained.

  3. Since the spacer is in contact with the structure having a step on the thin film transistor array substrate, the color filter substrate and the thin film transistor array substrate can be easily aligned during assembly. Therefore, the assembly time for each liquid crystal display panel is shortened and productivity is improved.

  4). Since one end of the spacer has a smooth surface, large tolerances are allowed during assembly. This often facilitates the process of aligning and connecting the color filter substrate and the thin film transistor array substrate together.

  5. In combination with spacer-on-color filter (SOC) technology, spacers can be formed on the color filter substrate, so no additional costs are incurred.

  It should be understood that both the foregoing general description and the following detailed description are exemplary and are intended to further describe the claimed invention in the claims.

  The accompanying drawings are included to enable a further understanding of the present invention, and the drawings are incorporated in the present specification and constitute a part of the present specification. The drawings illustrate embodiments of the invention and, together with the detailed description of the invention, serve to explain the principles of the invention.

  BEST MODE FOR CARRYING OUT THE INVENTION The best mode for carrying out the present invention will be described below in detail with reference to the accompanying drawings illustrating the present invention. When referring to the same or similar parts, the same reference numerals are used in the drawings and the present embodiment as much as possible.

  FIG. 2 is a perspective view showing a part of a liquid crystal display panel according to an embodiment of the present invention. As shown in FIG. 2, the liquid crystal display panel 200 includes a color filter substrate 210, a thin film transistor array substrate 220, a liquid crystal layer 230, and a plurality of spacers 250. The thin film transistor array substrate 220 has a plurality of gate layer lines and a plurality of source layer lines thereon. In one embodiment, for example, the gate layer line comprises a scan line 222 a and the source layer line comprises a data line 224. In another preferred embodiment, for example, the gate layer line comprises a scan line 222a and a common line 222b (shown in FIG. 4), and the source layer line comprises a data line 224. In addition, the liquid crystal display panel 200 may further include a sealant (not shown) provided on a portion near the edge of the color filter substrate 210 and the thin film transistor array substrate 220. The sealant mainly serves as an intermediate element for connecting the color filter substrate 210 and the thin film transistor array substrate 220 together, and also serves to enclose the liquid crystal layer 230 and the spacer 250 in the liquid crystal display panel. Fulfill. Note that the function and design of the sealant should be familiar to those skilled in the art of manufacturing liquid crystal display panels, and detailed description thereof will be omitted.

  As shown in FIG. 2, the spacer 250 is disposed on the color filter substrate 210 and in a region where the scanning line 222 a and the data line 224 overlap. Actually, each of the spacers 250 is in contact with one corner of the overlapping region of the scanning line 222a and the data line 224. Therefore, the color filter substrate 210 can be firmly locked to the thin film transistor array substrate 220 via the spacer 250 in order to obtain high bonding stability.

  In the above-described embodiment, the color filter substrate and the thin film transistor array substrate are fixed at predetermined positions through the spacers using the structure having a step on the thin film transistor array substrate. In addition to the embodiments described above, several other variations having different numbers of spacers and layouts on the thin film transistor array substrate are possible. Other types of layouts for spacers are described below.

  3 to 6D are top views showing layouts of various types of spacers in the liquid crystal display panel according to the present invention. In order to simplify the drawing, the color filter substrate is not shown in FIGS. 3 to 6D. First, as shown in FIG. 3, the spacer 250 is located in a corner area on the diagonal line of the overlapping area of the scanning line 222 a and the data line 224. In FIG. 4, the spacers 250 are located in all four corner regions of the overlapping region of the common line 222 b and the data line 224. Of course, the spacer may be arranged in the corner area of the overlapping area between the scanning line 222a and the data line 224 in addition to the overlapping area between the common line 222b and the data line 224. Alternatively, as shown in FIGS. 5A to 5C, select a spacer such as any one corner region, any pair of diagonal corner regions, adjacent corner regions, or three corner regions. May be arranged.

  6A to 6D are top views showing various types of layouts of the spacers 250 that are in contact with the edges of the scanning lines 222a and the data lines 224. FIG. As shown in FIGS. 6A to 6D, the spacer 250 can be selectively positioned on both sides or one side of the scan line 222 a and the data line 224.

  In the present invention, since the spacer is disposed close to a structure having a step such as a scanning line, a common line, or a data line on the thin film transistor array substrate, the assembled liquid crystal display panel has high coupling stability. Have. However, the above-described embodiments are merely exemplary functions. Those skilled in the art can design various designs by integrating the layouts disclosed in the present invention in various combinations to optimize the combined display panel. For example, spacers may be selectively disposed on the corner area of the overlapping area of the scanning line and the data line, the corner area of the overlapping area of the common line and the data line, and on both sides of the scanning line and the data line. Good. Furthermore, the number of spacers can be changed to reflect the processing conditions and actual demands.

  It should be noted that the spacer is not limited to a cylindrical cross section as in the above-described embodiment. In other embodiments of the present invention, the spacer may have a polygonal cross section or a wall cross section. 7 and 8 are top views showing two different types of layouts of wall spacers inside the liquid crystal display panel according to the present invention. In order to simplify the illustration, the color filter substrate of FIGS. 7 and 8 is not shown. First, as shown in FIG. 7, the wall spacer 260 is disposed so as to abut against the two side edges of the data line 224. The assembled liquid crystal display panel is reinforced by the wall spacer 260. In FIG. 8, wall spacers 260 having a right-angled cross section are in contact with the four corner regions of the overlapping region of the scanning lines 222a and the data lines 224. Of course, in other embodiments, the corner area of the overlapping area of the scanning line and the data line, the corner area of the overlapping area of the common line and the data line, or the wall on each side of the scanning line or the data line A spacer may be selectively disposed. The layout of the wall spacer is the same as that of the cylindrical spacer described above, and a detailed description thereof is omitted.

  In addition, some of the spacers described above may be coupled together to form a locking structure to provide additional strength to the assembled liquid crystal display panel. FIG. 9 is a schematic cross-sectional view showing a part of a liquid crystal display panel according to a preferred embodiment of the present invention. As shown in FIG. 9, the pair of spacers 250 on both sides of the data line 224 are connected together at the base adjacent to the color filter substrate 210. Thus, the pair of spacers 250 together form a hook-shaped locking structure 252. The locking structure 252 has a central recess 252 a corresponding to the position of the data line 224. The spacers in all the layouts of the above-described embodiments can be similarly connected to form a locking structure. For example, the spacers in the corner region of the overlapping region of the gate layer line and the source layer line are connected together to form a claw-like locking structure that locks to the overlapping region of the corresponding gate layer line / source layer line May be.

  10A to 10D are schematic cross-sectional views showing steps for forming the color filter substrate according to the present invention. As shown in FIG. 10A, a glass substrate 202 is prepared. Then, the black matrix 204 is formed on the glass substrate 202 and is formed so as to surround the plurality of openings 204 a on the glass substrate 202. The black matrix 204 may be formed by, for example, coating a black photosensitive material layer (not shown) on the glass substrate 202 by vapor deposition or sputtering, or by depositing a metallic material, and the black photosensitive material layer or metal. It is formed by patterning the layer.

  As shown in FIG. 10B, a plurality of color filter units 206 are formed in the opening 204a. The color filter unit 206 includes, for example, a red filter unit, a green filter unit, and a blue filter unit. The color filter unit 206 is formed, for example, by sequentially forming a color photosensitive material layer (not shown) on the glass substrate 202. Thereafter, a color filter unit 206 having various colors is formed in each opening 204a through exposure and development.

  As shown in FIG. 10C, a plurality of spacers 250 are formed on the black matrix 204. After the color filter substrate 210 and the thin film transistor array substrate 220 are connected together, the spacer 250 is disposed so as to abut against the edge of the scanning line 222 and the data line 224 (see FIG. 2). Of course, the spacer 250 may be disposed at a position adjacent to the structure having a step on the thin film transistor array substrate 220 according to the above-described embodiment. The spacer 250 is formed, for example, by depositing an organic photosensitive material on the glass substrate 202 and patterning the organic photosensitive material layer (not shown) in an exposure process and a development process. Here, it should be noted that the above-described locking structure is formed on the color filter substrate 202 by processing an organic photosensitive material layer (not shown) in a plurality of patterning operations.

  As shown in FIG. 10D, after the spacer 250 is formed on the color filter substrate 202, a post-baking operation may be performed. Usually, the open end of the spacer 250 (the end away from the glass substrate 202) has a smooth surface 250a. The smooth surface 250a of the spacer 250 facilitates the positioning of the two substrate color filter substrates and the thin film transistor array substrate and allows a large tolerance for assembly of the liquid crystal display panel.

  After the formation of the color filter substrate is completed, the color filter substrate and the thin film transistor array substrate are assembled together to form a liquid crystal display panel. The spacer on the color filter substrate is in contact with at least one side edge of the gate layer line or the source layer line on the thin film transistor array substrate. Therefore, the spacer not only maintains a constant distance between the color filter substrate and the thin film transistor array substrate, but also fixes the mutual position of the color filter substrate and the thin film transistor array substrate. In addition, since the spacer strengthens the assembled liquid crystal display panel against vibration and external force, the color filter substrate and the thin film transistor array substrate are rarely separated from their assembled positions.

  It will be readily apparent to those skilled in the art that various modifications and variations can be made to the structure of the present invention without departing from the scope or spirit of the invention. In view of the above, the present invention is intended to cover improvements and modifications of this invention, and such improvements and modifications are included within the scope of the claims and their equivalents.

It is a schematic cross-sectional view of the structure of a conventional liquid crystal display panel. 1 is a perspective view illustrating a part of a liquid crystal display panel according to an embodiment of the present invention. It is a top view which shows the layout of the spacer in the liquid crystal display panel which concerns on one Example of this invention. It is a top view which shows the layout of the spacer in the liquid crystal display panel which concerns on one Example of this invention. It is a top view which shows the layout of the spacer in the liquid crystal display panel which concerns on one Example of this invention. It is a top view which shows the layout of the spacer in the liquid crystal display panel which concerns on one Example of this invention. It is a top view which shows the layout of the spacer in the liquid crystal display panel which concerns on one Example of this invention. It is a top view which shows the layout of the spacer in the liquid crystal display panel which concerns on one Example of this invention. It is a top view which shows the layout of the spacer in the liquid crystal display panel which concerns on one Example of this invention. It is a top view which shows the layout of the spacer in the liquid crystal display panel which concerns on one Example of this invention. It is a top view which shows the layout of the spacer in the liquid crystal display panel which concerns on one Example of this invention. It is a top view which shows one of the layout of the wall-shaped spacer inside the liquid crystal display panel which concerns on this invention. It is a top view which shows one of the layout of the wall-shaped spacer inside the liquid crystal display panel which concerns on this invention. 1 is a schematic cross-sectional view showing a part of a liquid crystal display panel according to an embodiment of the present invention. It is a schematic cross-sectional view showing a process for forming a color filter substrate according to an embodiment of the present invention. It is a schematic cross-sectional view showing a process for forming a color filter substrate according to an embodiment of the present invention. It is a schematic cross-sectional view showing a process for forming a color filter substrate according to an embodiment of the present invention. It is a schematic cross-sectional view showing a process for forming a color filter substrate according to an embodiment of the present invention.

Explanation of symbols

200 liquid crystal display panel 202 glass substrate 204 black matrix 204a opening 206 color filter unit 210 color filter substrate 220 thin film transistor array substrate 222a scanning line 222b common line 224 data line 230 liquid crystal layer 250 spacer 250a smooth surface 252 locking structure 252a central recess 260 Wall spacer

Claims (14)

A color filter substrate;
A thin film transistor array substrate disposed in parallel with the color filter substrate;
A plurality of spacers disposed on the color filter substrate;
A liquid crystal layer disposed between the color filter substrate and the thin film transistor array substrate,
The thin film transistor array substrate has a plurality of gate layer lines and a plurality of source layer lines thereon,
The spacer is in contact with at least one side edge of a plurality of side edges of the gate layer line or the source layer line.   The liquid crystal display panel according to claim 1, wherein the gate layer line includes a scanning line, and the source layer line includes a data line.   The liquid crystal display panel according to claim 2, wherein the gate layer line further includes a common line.   4. The spacer according to claim 1, wherein the spacer is disposed in an overlapping area between the gate layer line and the source layer line and is in contact with both the gate layer line and the source layer line. A liquid crystal display panel according to any one of the above.   The adjacent spacers are connected together on the color filter substrate to form a locking structure, and a central recess of the locking structure is an overlapping area between the gate layer line and the source layer line. The liquid crystal display panel according to claim 1, wherein the liquid crystal display panel can be locked onto the liquid crystal display panel.   The liquid crystal display panel according to claim 1, wherein the spacer is disposed on both sides of the gate layer line and is in contact with the gate layer line.   The adjacent spacers are connected together on the color filter substrate to form a locking structure, and a central recess of the locking structure can be locked on the gate layer line. Item 7. A liquid crystal display panel according to item 6.   The liquid crystal display panel according to claim 1, wherein the spacer is disposed on both sides of the source layer line and is in contact with the source layer line.   The adjacent spacers are connected together on the color filter substrate to form a locking structure, and a central recess of the locking structure can be locked onto the source layer line. Item 9. A liquid crystal display panel according to Item 8.   The liquid crystal display panel according to claim 1, wherein the spacer has a cylindrical shape or a wall shape. Preparing a thin film transistor array substrate;
Preparing a color filter substrate;
Connecting the thin film transistor array substrate and the color filter substrate together,
The thin film transistor array substrate has a plurality of gate layer lines and a plurality of source layer lines thereon,
The color filter substrate has a plurality of spacers thereon,
The thin film transistor substrate and the color filter substrate may be configured such that the spacer on the color filter substrate is at least one side edge of a plurality of side edges of the gate layer line or the source layer line of the thin film transistor array substrate. A method for forming a liquid crystal display panel, which is coupled together so as to abut against a portion. The color filter substrate is
Preparing a glass substrate;
Forming the black matrix on the glass substrate such that the black matrix surrounds a plurality of openings on the glass substrate;
Forming a plurality of color filter units in the openings surrounded by the black matrix;
Forming a plurality of spacers on the black matrix. The step of forming the spacer includes
Forming an organic photosensitive material layer on the glass substrate;
And patterning the organic photosensitive material layer.   14. A method according to claim 12 or 13, comprising post-baking the spacer after forming the spacer.

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