JP2011145377A - Photomask, color filter substrate, pixel electrode substrate, liquid crystal display device, method for producing color filter substrate, and method for producing pixel electrode substrate - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a color filter substrate or a pixel electrode substrate, both of which scarcely having fluctuation irrespective of a process condition, and methods for producing them, by optimizing a photomask for simultaneously forming a fixed spacer and a sub-fixed spacer with different heights for controlling a cell gap by using a positive photoresist on the color filter substrate or on the pixel electrode substrate for a liquid crystal display device, and to provide a high-quality liquid crystal display device. <P>SOLUTION: The photomask 20 is used for forming the fixed spacer 5 for controlling the liquid crystal cell gap and the sub-fixed spacer 55 which is lower than the fixed spacer by one operation, by using the positive photoresist on the color filter substrate 11 or on the pixel electrode substrate in the liquid crystal display device, has a gray tone portion 9 including a total transmission slit on the periphery of a light-shielding portion 8 as a photomask pattern, and further has another total transmission slit or a total transmission opening in the vicinity of an inside center of the light-shielding portion in a photomask pattern of the sub-fixed spacer. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a liquid crystal display device, and in particular, a color filter substrate having a fixed spacer for forming a liquid crystal cell, a pixel electrode substrate, a method for manufacturing the color filter substrate and the pixel electrode substrate, and the color filter substrate and the pixel. The present invention relates to a photomask used for manufacturing an electrode substrate.

  2. Description of the Related Art In recent years, flat display devices have been widely used, and in particular, LCDs (liquid crystal display devices) are multicolor types that perform color display using color filters, especially for display panels such as televisions, monitors, and portable terminals. Use is progressing. In order to make multicolor, a color filter substrate having a micro cell structure is generally used, and the color filter substrate plays an important role in determining the display quality of the liquid crystal display panel.

  An LCD (Liquid Crystal Display) has a cell structure in which liquid crystal is sealed between a pair of substrates having at least one light-transmitting substrate. A color filter is formed on the inner surface of the cell. As shown in FIG. 7, the general configuration of the color filter substrate on which the color filter is formed is a light-blocking black matrix pattern 2 (abbreviated as BM pattern) on one side of the transparent substrate 1 (the side that becomes the inner surface of the liquid crystal cell). The same applies hereinafter) and the repeated arrangement of the colored patterns 30, 31, and 32 for each color filter pixel that regularly fills the gap between the BM pattern 2 is formed by accurate alignment, and, for example, TN (twisted nematic) is formed by a liquid crystal display method. In the case of the type, the transparent electrode layer 4 is formed so as to cover the repeated arrangement of the BM pattern 2 and the colored patterns 30, 31, 32. In the past, the color filter substrate used to refer to the components described so far, but in recent years, especially as liquid crystal cells have become larger and narrower, they have been dispersed in the cell forming process for cell gap control. Instead of the bead spacers, a plurality of fixed spacers (abbreviated as PS portions; hereinafter the same) 5 selectively formed by a photosensitive resin, called photo spacers, post spacers, etc. are often regularly arranged. Further, the PS section 5 is not provided on the color filter substrate side, as shown in the schematic diagram for explaining the cross-sectional structure of the LCD panel in FIG. 6, and is on the side opposite to the color filter substrate constituting the liquid crystal cell structure. It can also be provided on the pixel electrode substrate 12.

  A general example of forming the PS portion by a photographic method is shown in FIG. This is an example of forming a color filter substrate (PS portion formation) 11 as a whole structure in which a new PS portion is added to a conventional color filter substrate (PS portion unformed) 10 having a limited function. The photomask 20 corresponds to a new PS portion pattern formed on the color filter substrate (PS portion unformed) 10 by the light shielding portion 8 formed on the transparent substrate 21, and is opposite to the light shielding portion 8 of the transparent substrate 21. The irradiation light 40 irradiated from the side passes through the portion without the light shielding portion 8 and selectively exposes the positive type photoresist 7 applied on the color filter substrate (PS portion unformed) 10 to develop and dissolve it. give. Thereafter, the light shielding part pattern is baked and fixed on the color filter 10 through development, washing, and baking processes.

  The PS section 5 has a function of maintaining a liquid crystal cell gap constant by forming a pattern having the same shape in a regular arrangement selectively determined so as to overlap the BM pattern 2. For the purpose of ensuring a sufficient height for obtaining the cell gap, three colored patterns 30, 31, 32 of red (R), green (G), and blue (B) are overlaid on the BM pattern 2, It is also possible to compensate for the height of only the PS section (see Patent Document 1).

  It is important that the PS unit 5 sufficiently exhibits a function of keeping the liquid crystal cell gap constant against various external pressures. Even after the paneling process, the liquid crystal panel often receives strong pressure from the outside, for example, by polishing the glass substrate from the outside for thinning the panel or using it in combination with a touch panel. Naturally, the strength and elastic characteristics of the material constituting the PS portion are improved so that the PS portion 5 does not collapse against such a strong pressure. There has been an increasing number of measures taken to form the fixing spacer slightly lower than the PS portion as the fixed spacer and use it together with the PS portion.

  Many proposals have been made for forming the PS portion 5 using a positive photoresist, but there are many problems, and at present, a negative photoresist is often used for forming the PS portion. The reason why the positive type photoresist is not always realized despite the advantage that it can be processed at a low material cost is that the control of the height shown in the PS sections 51 and 52 is explained as shown in FIG. This is because of the above-mentioned difficulty and the quality abnormality due to the depression of the upper surface shown in the PS portion 53. That is, in the small PS portions 51 and 52 having a planar size of less than 30 μm, variations in exposure amount and exposure gap with respect to a thickly applied photoresist film are sensitive to development thickness, that is, variations in PS portion height d. The function of the PS section giving a certain height that is particularly important for cell gap control is impaired. In addition, in the large PS portion 53 having a planar size of 30 μm or more, a dent e is generated on the upper surface of the PS portion, which causes a problem that in the liquid crystal cell manufacturing process, quality abnormality is caused when applying an alignment film.

  Further, when a low sub-fixing spacer referred to as the sub-PS is added to the PS portion and appropriately arranged in a batch process, two types of fixing spacers and sub-fixing spacers that maintain a constant height difference are used. Since it is necessary to process the protrusions at the same time while properly controlling the shape, there are more manufacturing difficulties.

  On the other hand, with respect to the control of the thickness of the thickly coated photoresist film as described above, an intermediate exposure amount between a region that provides a sufficient exposure amount and a region that shields light is applied, and the height of the protrusion is set to an intermediate level. There is a way to make it. As a method of forming an intermediate density pattern on a photomask, an average of the entire fine pattern area is semi-translucent by a collection of fine patterns of light shielding films such as dot (halftone dot) arrangement and line and space. There are two types of gray-tone masks: a general gray-tone mask type that corresponds to the part, and a half-tone mask type that forms a uniform semi-transparent part by directly forming a film having semi-transparent film characteristics and patterning means. (Patent Document 2).

  Further, in FIG. 7, in the method of raising the portion corresponding to the base of the PS portion 5 by overlapping two or more of the colored patterns 30, 31, 32 on the BM pattern 2, and consequently forming the PS portion high, Since the thickness of the dedicated layer formed in the process as the PS portion 5 does not necessarily need to be particularly thick, the problems in the case of using the above positive photoresist can be largely avoided. However, when the colored patterns 30, 31, 32 are stacked to partially bulge the BM pattern 2, both the accuracy of application of the material forming each colored pattern and the accuracy of alignment of the overlapping are controlled with extremely high accuracy. This is particularly important and often involves difficulties in stabilizing the production process.

Japanese Patent No. 3651874 JP 2007-248988 A

  The present invention is proposed in view of the above-mentioned problems, and the problem to be solved by the present invention is to control cell gap by using a positive photoresist on a color filter substrate or a pixel electrode substrate for a liquid crystal display device. Optimized photomasks for simultaneously forming fixed spacers and sub-fixed spacers with different heights, and provides a color filter substrate and its manufacturing method with little variation due to process conditions, or a pixel electrode substrate and its manufacturing method It is to provide a high-quality liquid crystal display device.

  As a means for solving the above problems, the invention described in claim 1 is a color filter substrate having a color filter in a liquid crystal display device, or a pixel having a switching element and a pixel electrode for active driving of the liquid crystal display device. A photomask for forming a fixed spacer for controlling a liquid crystal cell gap and a sub-fixed spacer lower than the fixed spacer by using a positive photoresist on an electrode substrate, wherein the photomask pattern of the fixed spacer is shielded from light A gray tone portion including a total transmission slit around the light shielding portion, and a photomask pattern of the auxiliary fixing spacer having a gray tone portion including a total transmission slit around the light shielding portion, and the inside of the light shielding portion. It has other total transmission slit or total transmission opening near the center of It is a photo-mask.

  According to a second aspect of the present invention, the planar shape of the fixed spacer and the sub-fixed spacer is a convex simple polygon or a circle such as a circle or an ellipse, and the sizes thereof are the fixed spacer and the sub-fixed spacer. The diameter of the maximum circle that can be accommodated in the contour of the light-shielding part is 30 to 50 μm, so that the width of the total transmission slit of the gray tone part provided around the light-shielding part is 5 to 7 μm, and the inside of the light-shielding part 2. The photomask according to claim 1, wherein the total size of the light shielding portion and the gray tone portion around the light shielding portion is 30 μm or more.

  In the invention according to claim 3, the width of another total transmission slit provided near the center inside the light shielding portion is set to 2 to 3 μm, or the width of the total transmission opening is set to 6 to 7 μm. The photomask according to claim 1, wherein the photomask is a photomask.

  According to a fourth aspect of the present invention, there is provided a photomask according to any one of the first to third aspects, wherein the fixed spacer and the sub-fixed spacer are selectively provided on a color filter substrate. It is a color filter substrate.

  According to a fifth aspect of the present invention, the height of the fixed spacer from the color filter pixel center outermost surface is 2.0 to 3.8 μm, and the sub-fixed spacer from the color filter pixel central outermost surface. The color filter substrate according to claim 4, wherein the height of the color filter substrate is lower by about 0.4 μm than that of the fixed spacer.

  According to a sixth aspect of the present invention, the photomask according to any one of the first to third aspects is used, and the fixed spacer and the sub-fixed spacer are selectively provided on the pixel electrode substrate. This is a pixel electrode substrate.

  According to a seventh aspect of the present invention, the height of the fixed spacer from the outermost surface of the pixel electrode central portion is 2.0 to 3.8 μm, and the height of the sub-fixed spacer from the outermost surface of the pixel electrode central portion is set. The pixel electrode substrate according to claim 6, wherein the height is about 0.4 μm lower than that of the fixed spacer.

  The invention according to claim 8 is a liquid crystal display device comprising the color filter substrate or pixel electrode substrate according to any one of claims 4 to 7.

  According to a ninth aspect of the present invention, a collective pattern is formed by a proximity exposure method using the photomask according to any one of the first to third aspects, and the fixed spacer and the sub-fixed spacer are placed on a color filter substrate. A method for manufacturing a color filter substrate, which is selectively provided.

  According to a tenth aspect of the present invention, a collective pattern is formed by a proximity exposure method using the photomask according to any one of the first to third aspects, and the fixed spacer and the sub-fixed spacer are formed on the pixel electrode substrate. A method of manufacturing a pixel electrode substrate, which is selectively provided.

  When forming fixed spacers and sub-fixed spacers for controlling cell gaps on color filter substrates for liquid crystal display devices, if the planar size of the spacers is small, variations in the exposure gap and exposure amount greatly affect the finished height of the spacers. In addition, when the planar size of the spacer is large, the portion that should be flat on the upper surface of the spacer is recessed, so that a positive photoresist is effective as a spacer, such as a quality error when applying an alignment film in the liquid crystal cell manufacturing process. However, with the inexpensive photomask having the gray tone portion of the present invention, the high-quality fixed spacer and the sub-fixed spacer whose height is lowered by a certain amount are colored with a positive photoresist. They can be formed collectively on the filter substrate or the pixel electrode substrate.

  According to the invention described in claim 2 or 3, a large planar size spacer particularly suitable for the fixed spacer and the sub-fixed spacer constituting the color filter substrate or the pixel electrode substrate of the present invention can be stably and highly provided. The structure of the photomask to be realized with quality can be defined.

  In addition, according to the invention described in claim 4 or 6, a color filter substrate or pixel electrode substrate having high-quality fixed spacers and sub-fixed spacers uniformly can be obtained at a low material cost, and the obtained color filter substrate Alternatively, the pixel electrode substrate can be adapted to the liquid crystal cell formation process without any abnormality and contribute to the production of a high quality liquid crystal cell.

  Further, according to the invention described in claim 5 or 7, the height particularly suitable for the fixed spacer and the sub-fixed spacer constituting the color filter substrate or the pixel electrode substrate of the present invention can be realized stably and with high quality. Therefore, the obtained color filter substrate or pixel electrode substrate can be adapted to the liquid crystal cell formation process without any abnormality, and can further contribute to the production of a high quality liquid crystal cell.

  According to the invention described in claim 8, a liquid crystal display device including a color filter substrate or a pixel electrode substrate with stable quality can be provided with high quality.

  Further, according to the invention described in claim 9 or 10, a color filter substrate or pixel electrode substrate having uniform high-quality fixed spacers and sub-fixed spacers can be obtained with a low material cost and a stable process. The high yield can improve productivity, and can easily cope with the change in the specifications of the color filter substrate and the pixel electrode substrate without greatly changing the manufacturing process conditions.

It is a conceptual cross-sectional view for explaining the relationship between the photomask of the present invention and the corresponding PS portion and sub-PS. It is a cross-sectional conceptual diagram for demonstrating the general method of forming PS part in a color filter substrate. It is a cross-sectional conceptual diagram for demonstrating the condition where the cross-sectional shape of the conventional PS part produces a malfunction. It is a conceptual cross-sectional view for explaining a situation in which a PS portion and a sub-PS are formed in an optimal cross-sectional shape on the color filter substrate of the present invention. It is a plane conceptual diagram for demonstrating an example of the photomask pattern for forming one PS part with the photomask of this invention. It is a conceptual cross-sectional view for explaining an example of the liquid crystal display device of the present invention. It is a conceptual cross-sectional view for explaining a general configuration of a color filter substrate. It is a cross-sectional conceptual diagram for demonstrating the height of PS part formed on a color filter substrate. It is a plane conceptual diagram for demonstrating the example of the photomask pattern for forming one sub PS with the photomask of this invention, Comprising: Two types (a) and (b) are shown.

  Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings.

  FIG. 2 is a cross-sectional conceptual diagram illustrating a general configuration of the color filter substrate in FIG. 7, and shows a general method for forming a new PS portion 5 on a conventional color filter substrate having no PS portion. This will be described with reference to a conceptual diagram. After forming the BM pattern 2 and the colored patterns 30, 31, 32 on the transparent substrate 1 by repeating different three colors such as red, green, and blue, the color filter substrate on which the transparent electrode layer 4 is formed (PS portion not formed) ) A positive type photoresist 7 is formed on 10 by coating. The positive photoresist 7 is a material for making the PS portion 5 and may be selected in consideration of shape quality including its height accuracy and elastic characteristics. For example, a commercially available novolac resin-based positive photoresist is applied at a dry height of about 3 to 4 μm, but is not limited thereto. The application method is preferably a method with high use efficiency of a photoresist such as a die coating method, but is not particularly limited as long as it can be applied uniformly.

  In FIG. 2, the positive type photo resist 7 is applied and dried to face the color filter substrate 10, the pattern surface of the photo mask 20 is brought close to the opposing surface while being aligned, and exposure for resist exposure from the back side of the photo mask is performed. Exposure is performed with light 40. In the exposure step, g-rays (436 nm), h-rays (405 nm), i-rays from an ultra-high pressure mercury lamp that is easy to obtain high-intensity and parallel light by a collective exposure machine for proximity exposure generally used for manufacturing color filters. With a line (365 nm) as the main wavelength, exposure is performed according to the photoresist sensitivity with an exposure gap of about 100 to 150 μm. Thereafter, through a process of development, washing, and baking, a protruding pattern corresponding to the light-shielding portion 8 of the photomask is formed as a PS portion 5 with a photoresist.

  Here, the situation of the shape defect of the PS portion described above will be described in more detail with reference to FIG. 3. In the PS portions 51 and 52 having a planar size of less than 30 μm, the exposure amount and the proximity to the thickly applied photoresist film are determined. Variations in the exposure gap of the exposure method sensitively affect the development thickness, more precisely, the height of the PS portion after baking, resulting in variations d. For this reason, the function which gives the constant height especially important for cell gap control is impaired. Further, in the PS portion 53 having a planar size of 30 μm or more, a dent e is generated on the upper surface of the PS portion, resulting in poor alignment in the liquid crystal cell manufacturing process and causing a quality abnormality.

All of the above phenomena have been found to involve the bulge of the pattern edge due to baking. For example, when confirmed with an example of a regular octagonal shading pattern, a tendency that the bulge of the peripheral edge due to baking is particularly large is observed. Rather, fluctuations in exposure conditions tend to greatly affect the final height variation. On the other hand, in the case of a PS portion having a planar size of 30 μm or more,
A dent on the upper surface of the PS portion is generated. Based on the above knowledge, we considered that it is possible to provide a common improvement measure for each of the above-mentioned plane sizes by providing a region for reducing fluctuations in exposure conditions and thermal deformation at the edge of the photomask pattern. Its effectiveness was confirmed. As a result of intensive studies, the inventors have found a design guideline for a photomask that is particularly convenient for forming a PS portion having a planar size of 30 μm or more without a recess in the upper surface.

  The occurrence of variation in the height of the PS portion and the depression on the upper surface similarly occurs in the sub-PS in which the design value of the height is lowered by about 0.4 μm. In particular, the design guideline for a photomask that is convenient for forming a PS portion and a sub-PS having a planar size of 30 μm or more without a dent on the upper surface is common to both the PS portion and the sub-PS. In addition, in order to realize a certain film thickness difference with good reproducibility when forming both protrusion patterns in the same process, a special device is further included in the sub-PS photomask.

  FIG. 1 is a conceptual cross-sectional view for explaining the relationship between the photomask of the present invention and the corresponding PS portion and sub-PS. The photomask of the present invention is positively applied to a color filter substrate 11 having a color filter in a liquid crystal display device or a pixel electrode substrate 12 (FIG. 6 described later) having a switching element and a pixel electrode for active driving of the liquid crystal display device. A photomask 20 for collectively forming a fixed spacer (PS portion 5) for controlling a liquid crystal cell gap and a sub-fixed spacer (sub-PS55) lower than the fixed spacer using a type photoresist 7, The photomask pattern has a gray tone portion 9 including a total transmission slit around the light shielding portion 8, and the photomask pattern of the auxiliary fixing spacer includes a gray tone portion 9 including a total transmission slit around the light shielding portion. And have other totally transmissive slits or transmissive holes near the center of the inner side 85 of the light shielding portion. It is characterized in that it has an opening.

  As in the case shown in FIG. 2, the transparent substrate 21 of the photomask has a wavelength in a region that uses at least the photosensitivity of the photoresist 7 used for the PS portion 5 among the irradiation light 40 for resist exposure from the exposure machine. Such as fused silica glass and alkali-free glass. Further, in the production of the photomask 20, the light shielding portion 8 is formed by patterning a metal chromium film, which has been mainly formed by a sputtering method, or a thin film of a low reflection film in which chromium oxide is laminated on metal chromium by a photo etching method. In general, the etching means may be wet or dry. Further, the gray tone portion 9 can be formed of the same material as the light shielding portion 8 and by a device on the pattern such as a slit in the same process as the formation of the light shielding portion. The sub PS photomask pattern can also be formed by a combination of the above-described thin film forming method and photoetching method.

  FIG. 4 is a conceptual cross-sectional view for explaining a situation where the PS portion and the sub-PS are formed in an optimal cross-sectional shape on the color filter substrate of the present invention. For example, trapezoidal protrusions having a regular octagonal horizontal cross section are formed on the color filter substrate 11 as the PS portion and sub-PS, and various sizes are conveniently provided as PS portions 51 and 53 and sub-PS 55 and 54. , Displayed adjacent to each other on the same drawing. If the plane size of the PS portion and the sub-PS is represented by regarding the distance between two opposing sides of the lower bottom portion as the diameter of the difference, this plane size becomes an object of each of the above-described two classified plane sizes. In the present invention, a common improvement measure is implemented for both 51 and 55 having a PS and sub-PS plane size of less than 30 μm and 53 and 54 having a plane size of 30 μm or more. This is an effective method for forming 53 and 54 having a planar size of 30 μm or more. Of the patterns on the photomask corresponding to each PS section and sub-PS, 81, 83, 85, and 84 are the light shielding parts or the inner side of the light shielding parts, and 91, 93, and 95 are the gray tone parts around the light shielding parts, respectively. , 94.

Since the PS section needs to exhibit a function as a fixed spacer for constituting a liquid crystal cell,
It is desirable to have a uniform height and shape and elastic properties uniformly. The sub-PS is also slightly lower than the PS portion (the difference is represented by k in FIG. 4), which is necessary for the supplementary function of the PS portion. Therefore, it is desirable to have it uniformly. For this reason, it is not preferable that the planar size of the PS portion and the sub-PS constituting the large liquid crystal cell is too small from the viewpoint of the function and the production yield. Actually, it is desirable that the size of the fixed spacer and the sub-fixed spacer is 20 μm or more.

  In the photomask 20 of the present invention, the patterns corresponding to the PS portions 5, 51, 53 on the color filter substrate 11 cover the patterns of the light shielding portions 8, 81, 83 as shown in FIGS. Gray tone portions 9, 91 and 93 are formed. The structure will be described with reference to FIG. For example, the regular octagonal light shielding portion 8 is covered so as to be surrounded by a gray tone portion 9 including a total transmission slit. In order for the photomask pattern to exert its effect on the formation of the PS portion, it is better to limit the sizes of the light shielding portion and the gray tone portion. As a result of the experimental study, the photomask pattern for forming the PS portion so that the plane size is 30 μm to 50 μm and the upper surface is not dented is the total transmission slit of the gray tone portion provided around the light shielding portion. It has been found that it is optimal to set the width c to 5 to 7 μm and the overall size a of the light-shielding portion and the gray tone portion to 30 μm or more.

  Note that, assuming that the light-shielding line width w of the gray tone portion is as thin as 1 to 2 μm, the light-shielding portion size b is between the light shielding portion and the overall size a of the gray tone portion and the light shielding portion size b in the photomask pattern. In addition, the planar size p of the PS portion formed of photoresist is located. That is, when expressed by a mathematical formula, there is a relationship of a ≧ p ≧ b.

  The planar shape of the PS portion provided as the fixed spacer is not limited to the regular octagon or the general circle described above, and can be used as long as it is a convex simple polygon or a circle such as a circle or an ellipse. . Here, the convex shape means that the inner angles of all the vertices of the polygon are less than 180 degrees. A simple polygon means a region surrounded by a closed multi-sided continuous chain that does not intersect each other. In the above generalized shape, the planar size p of the PS portion can be defined by the diameter of the largest circle that can be accommodated in the outline of the PS portion.

  The relationship between the planar size of the PS portion and the light-shielding portion and the gray tone portion of the photomask pattern is the same in the sub-PS, and is caused by the rise of the end portion of the projection pattern formed of photoresist. In improving the shape, it can be expressed more concretely as follows.

  In the photomask of the present invention, the planar shape of the fixed spacer and the sub-fixed spacer is a convex simple polygon or a circle such as a circle or an ellipse, and the size thereof is within the outline of the fixed spacer and the sub-fixed spacer. The photomask for forming the maximum circle that can be stored to have a diameter of 30 to 50 μm, wherein a width of a total transmission slit of a gray tone portion provided around the light shielding portion is 5 to 7 μm, and the light shielding portion 2. The photomask according to claim 1, wherein the total size including the inner side of the light and the gray tone portion around the light shielding portion is 30 μm or more.

  Further, a device on the photomask pattern for forming the sub-PS lower than the PS portion will be described with reference to FIG.

FIG. 9 is a schematic plan view for explaining an example of a photomask pattern for forming one sub-PS by the photomask of the present invention, and shows two types (a) and (b). (A) has a total transmission slit with a width s in the vicinity of the center inside the light-shielding portion 8 apart from the total transmission slit with a width c provided in the periphery of the light-shielding portion, and further has a width q on the inner side. It has a central shading part. Further, (b) has a total transmission opening having a width r in the vicinity of the center inside the light shielding portion 8. Shading part 8
Both types have a total transmission slit of width c and a light-shielding line of width w around the same as in the photomask pattern example for forming the PS portion shown in FIG.

  The size of the PS part and the sub-PS is 42 μm, and the height of the PS part is 2.7 μm. As a result of the experimental investigation, in the type (a), the width q of the central light shielding part is assumed to be 3 to 5 μm. By setting the width s of the total transmission slit to 2 to 3 μm, the height of the sub-PS can be formed to be moderately lower than the PS part by about 0.4 μm. In the (b) type, the height of the sub-PS can be appropriately lowered to about 0.4 μm from the PS portion by setting the width r of the central total transmission opening to 6 to 7 μm.

  The height of the PS portion provided as the fixed spacer is suitably 2.0 to 3.8 μm in consideration of the cell gap of the liquid crystal display device. However, as shown in the conceptual cross-sectional view for explaining the height of the PS portion formed on the color filter substrate in FIG. 8, the colored patterns 31 and 32 are formed on the BM pattern 2 so as to swell, and the swell is formed. When the PS part 5 is formed in the part via the transparent electrode layer 4, the height f of the PS part can be set lower by the height g of the raised part. In other words, if the height h from the outermost surface of the color filter pixel central portion at the lowest position to the upper bottom of the PS portion is set to 2.0 to 3.8 μm, it is equivalent to the case where there is no bulging portion. The above situation also applies to the sub-PS, and it is possible to reduce the height of the PS protrusion and the photoresist protrusion of the sub-PS that are actually formed depending on the overlapping state of the colored patterns on the BM pattern. In addition, it is appropriate to set the sub-PS to be low by setting the height difference k between the PS portion and the sub-PS to about 0.4 μm in consideration of the steps after the panel formation of the liquid crystal display device.

  The fixed spacer can be selectively provided on the color filter substrate by a photolithography method using the photomask of the present invention. In the exposure process, a proximity exposure system that maintains an exposure gap of 100 to 150 μm is suitable. As a result, an optimal color filter substrate constituting the liquid crystal display device can be provided.

  In the above description, the case where the PS portion and the sub-PS are formed mainly on the color filter substrate has been described. However, when the PS portion is formed on the pixel electrode substrate, the photomask of the present invention is used similarly. A positive photoresist for forming the PS portion and the sub-PS can be processed and formed by a photolithography method.

  Similarly to the case of the color filter substrate, the height from the outermost surface of the pixel electrode central portion of the PS portion is set to 2.0 to 3.8 μm on the pixel electrode substrate, and the height of the sub PS is set to the PS portion. It is optimal that the thickness be about 0.4 μm in consideration of the cell gap of the liquid crystal display device.

  FIG. 6 is a conceptual cross-sectional view for explaining an example of the liquid crystal display device of the present invention. In the figure, an alignment film 15 for liquid crystal alignment is formed on a transparent substrate 41, an active drive switching element 13 (usually using TFTs), and a pixel electrode substrate 12 in which a PS portion 5 and a sub-PS 55 are formed on the pixel electrode 14. The alignment film 15 is formed on the surface of the color filter substrate (PS portion not formed) 10 on the opposite side, and the liquid crystal 16 is sealed between the two substrates to form the cell structure with the sealant 17. close. An optical layer such as a polarizing plate 18 is appropriately disposed outside both substrates, and a backlight 19 is provided outside the pixel electrode substrate side. Except for the process of forming the PS portion 5 and the sub-PS 55 according to the present invention, the process can be performed in the same manner as the manufacturing process of a normal liquid crystal display device.

As described above, a liquid crystal display device can be manufactured using the color filter substrate or the pixel electrode substrate of the present invention. A color filter substrate or a pixel electrode substrate having the same configuration as that of the present invention is manufactured in the same manner as in the case of a liquid crystal display device that is manufactured by a conventional method. In the present invention, a liquid crystal display device with stable quality is manufactured. High quality can be provided. For example, the quality of the PS portion and sub-PS of the color filter substrate or the pixel electrode substrate does not vary in height, and there is no dent in the upper surface of the PS portion and sub-PS when the planar size is large. In the process of manufacturing the display device, no quality abnormality is caused in alignment film application.

1, 21, 41 ... Transparent substrate 2 ... BM pattern 4 ... Transparent electrode layer 5 ... PS part (fixed spacer)
7 ... Positive photoresist 8 ... Shading part 9 ... Gray tone part 10 ... Color filter substrate (PS part not formed)
11 ... Color filter substrate (PS part formation)
DESCRIPTION OF SYMBOLS 12 ... Pixel electrode substrate 13 ... Switching element 14 for active drive ... Pixel electrode 15 ... Orientation film 16 ... Liquid crystal 17 ... Sealant 18 ... Polarizing plate 19 ... Backlight 20 ... Photomask 30, 31, 32 ... Colored pattern 40 ... Irradiation light 51, 52, 53 ... for resist exposure PS part (fixed spacer)
54, 55 ... Sub-PS (Sub-fixing spacer)
81, 82, 83... Light shielding portion 84, 85... Inside the light shielding portion 91, 93, 94, 95.

Claims (10)

  A fixed spacer for controlling a liquid crystal cell gap using a positive photoresist on a color filter substrate having a color filter in a liquid crystal display device or a pixel electrode substrate having a switching element for active driving of the liquid crystal display device and a pixel electrode. A photomask for collectively forming sub-fixed spacers lower than the fixed spacer, wherein the photomask pattern of the fixed spacer has a gray tone portion including a total transmission slit around the light shielding portion, and the sub-fixation The spacer photomask pattern has a gray tone portion including a total transmission slit around the light shielding portion, and another total transmission slit or total transmission opening near the center inside the light shielding portion. Photo mask to be used.   The planar shape of the fixed spacer and the sub-fixed spacer is a convex simple polygon or a circle such as a circle or an ellipse, and the size of the maximum circle that can be stored in the contour of the fixed spacer and the sub-fixed spacer. In order to form 30 to 50 μm, the width of the total transmission slit of the gray tone portion provided around the light shielding portion is 5 to 7 μm, and the inside of the light shielding portion and the gray tone portion around the light shielding portion are 2. The photomask according to claim 1, wherein the total size is 30 μm or more.   3. The width of another total transmission slit provided near the center inside the light shielding portion is set to 2 to 3 [mu] m, or the width of the total transmission opening is set to 6 to 7 [mu] m. The photomask described in 1.   A color filter substrate using the photomask according to claim 1, wherein the fixed spacer and the sub-fixed spacer are selectively provided on the color filter substrate.   The height of the fixed spacer from the color filter pixel center outermost surface is set to 2.0 to 3.8 μm, and the height of the sub-fixed spacer from the color filter pixel central outermost surface is set to be higher than that of the fixed spacer. The color filter substrate according to claim 4, wherein the color filter substrate is lowered by about 0.4 μm.   A pixel electrode substrate comprising the photomask according to claim 1, wherein the fixed spacer and the sub-fixed spacer are selectively provided on the pixel electrode substrate.   The height of the fixed spacer from the outermost surface of the pixel electrode central portion is set to 2.0 to 3.8 μm, and the height of the sub-fixed spacer from the outermost surface of the pixel electrode central portion is set to 0. 0 from that of the fixed spacer. The pixel electrode substrate according to claim 6, wherein the pixel electrode substrate is lowered by about 4 μm.   A liquid crystal display device comprising the color filter substrate or the pixel electrode substrate according to claim 4.   A color filter, wherein the photomask according to claim 1 is used to form a collective pattern by a proximity exposure method, and the fixed spacer and the sub-fixed spacer are selectively provided on a color filter substrate. A method for manufacturing a substrate.   A pixel electrode, wherein the photomask according to claim 1 is used to form a collective pattern by a proximity exposure method, and the fixed spacer and the sub-fixed spacer are selectively provided on the pixel electrode substrate. A method for manufacturing a substrate.