JP2008164858A - Color filter substrate, manufacturing method thereof, and display device - Google Patents

Abstract

A color filter substrate, a method for manufacturing the color filter substrate, and a display device capable of maintaining a predetermined height of a photo spacer without adjusting the thickness of a colored layer or a protruding layer.
A step of forming a light-shielding layer having a predetermined pattern having a spacer formation region on a transparent substrate, and simultaneously disposing a plurality of pixel coloring layers in a two-dimensional manner in a region partitioned by the light-shielding layer, A step of sequentially stacking a plurality of color spacer coloring layers three-dimensionally on the spacer formation region of the light shielding layer, a step of forming a transparent conductive film on the pixel coloring layers and the spacer coloring layers of the plurality of colors, and the two Forming a photo spacer having a height Y from the upper surface of the transparent conductive film on the pixel coloring layers of a plurality of colors arranged in a dimension to the upper surface of the spacer protrusion layer, the height of the photo spacer The thickness of the light shielding layer is controlled in accordance with the thickness of the pixel coloring layer so as to obtain a desired value of Y.
[Selection] Figure 1

Description

  The present invention relates to a color filter substrate, a manufacturing method thereof, and a display device, and more particularly, to a color filter substrate for a multi-domain vertical alignment (MVA) mode liquid crystal display device, a manufacturing method thereof, and a liquid crystal display device.

  A liquid crystal display device has features such as a small size, a thin shape, low power consumption, and light weight, and thus is widely used in various display devices such as personal computers, television devices, and mobile phones.

  In such a liquid crystal display device, in order to maintain a predetermined thickness of the liquid crystal layer between both the color filter substrate and the thin film transistor (TFT) substrate, glass or resin spherical particles (beads) or rods called spacers are used. I was spraying my body inside the cell. Since this spacer exists as a foreign substance with respect to the liquid crystal, the alignment of the liquid crystal molecules in the vicinity of the spacer particles is disturbed, light leakage occurs in this portion, the contrast of the liquid crystal display device is lowered, and the display quality is adversely affected. Have the problem.

  As a technique for solving this problem, for example, by patterning a photosensitive resin layer by a photolithography method, a columnar resin spacer is formed on a black matrix having a lattice pattern at a desired position, for example, at a boundary between pixels. Has been proposed (see, for example, Patent Document 1). Such a spacer is hereinafter referred to as a photo spacer.

  Since the photo spacer can be formed at a position avoiding the pixels, improvement in display quality can be desired. Photo spacers are generally formed by applying a photosensitive resin composition to a substrate surface, drying, exposing to light through a photo mask having a predetermined fine pattern, developing, and baking.

  There has also been proposed a method of forming such a photo spacer by three-dimensionally laminating a plurality of colored layers at a predetermined position on the light shielding layer at the same time as forming a plurality of colored layers (for example, Patent Documents). 2). The height of the photo spacer in this case was maintained at a predetermined value by measuring the height immediately before forming the final laminated film and adjusting the film thickness of the final laminated film based on the measured value.

However, such a method for adjusting the height of the photo spacer has a problem in the case of a color filter substrate for a multi-domain vertical alignment (MVA) mode liquid crystal display device. That is, in a color filter substrate for an MVA mode liquid crystal display device, a vertical alignment rib (protrusion) is formed after forming a color filter composed of a plurality of colored layers. A layer made of the material constituting the rib is also formed on the plurality of formed colored layers, and this is the final laminated film. Therefore, if the thickness of the rib that will be the final laminated film is changed to adjust the height of the photo spacer, the thickness of the rib will deviate from the design value, resulting in problems such as a deterioration in viewing angle and a decrease in contrast. Will occur. Therefore, in order to obtain the height of the photo spacer, complicated adjustment of the thickness of the light shielding layer and the colored layer is required.
JP 2001-91954 A JP 2006-292497 A

  The present invention has been made under the circumstances as described above, and a color filter substrate capable of maintaining the height of a predetermined photo spacer without adjusting the thickness of a colored layer or a protruding layer, a manufacturing method thereof, and An object is to provide a display device.

  In order to solve the above-mentioned problems, a first aspect of the present invention is a method of forming a light-shielding layer having a predetermined pattern having a spacer formation region on a transparent substrate, two-dimensionally in the region partitioned by the light-shielding layer. Simultaneously arranging a plurality of color coloring layers on the spacer formation region of the light shielding layer, and sequentially stacking a plurality of color coloring layers on the spacer formation region of the light shielding layer, Forming a transparent conductive film, and forming a projection layer of a predetermined pattern on the transparent conductive film on the two-dimensionally arranged pixel colored layers, and simultaneously stacking the three-dimensionally A spacer protrusion layer is coated on the transparent conductive film on the plurality of colored spacer coloring layers, and the spacer protrusion layer is formed from the upper surface of the transparent conductive film on the two-dimensionally arranged pixel coloring layers. Height Y to the top surface of Forming a photo spacer, and controlling the thickness of the light shielding layer in accordance with the thickness of the pixel coloring layer so as to obtain a desired value of the height Y of the photo spacer. A method for manufacturing a color filter substrate is provided.

  According to a second aspect of the present invention, there is provided a transparent substrate, a light shielding layer having a predetermined pattern formed on the transparent substrate, having a spacer formation region, and a plurality of two-dimensionally arranged in regions partitioned by the light shielding layer. A colored pixel colored layer, a plurality of colored spacer colored layers three-dimensionally stacked on a spacer forming region of the light shielding layer, a transparent conductive film formed on the colored pixel colored layer and the spacer colored layer, A spacer projecting layer having a predetermined pattern disposed on the transparent conductive film on the pixel coloring layer, and a spacer projecting layer disposed on the transparent conductive film on the spacer coloring layer; In the color filter substrate, a photo spacer having a height Y from the upper surface of the transparent conductive film on the pixel coloring layer to the upper surface of the spacer protrusion layer is constituted by the transparent conductive film and the spacer protrusion layer. Serial shielding layer, so as to obtain a desired value of the height Y of the photo spacers, to provide a color filter substrate and having a thickness that is controlled according to the thickness of the pixel colored layer.

  In such a color filter substrate and the manufacturing method thereof, the thickness of the light shielding layer is controlled by calculating the amount of change in the height Y of the photo spacer that is assumed in accordance with the thickness of the pixel coloring layer. The amount of change in the thickness of the light shielding layer can be calculated, and the amount of change in the height Y of the photo spacer can be offset based on the amount of change in the thickness.

  In this case, the amount of change ΔY in the height Y of the photo spacer can be calculated based on the thickness X of the pixel coloring layer by the following equation (1).

ΔY = 1.0998X−1.5398 (1)
The thickness of the light shielding layer is controlled by calculating the amount of change ΔZ in the thickness of the light shielding layer from the following equation (2) from the amount of change ΔY in the height Y of the photospacer calculated by the equation (1). Can be performed.

ΔY = 0.4996ΔZ + 0.0008 (2)
A third aspect of the present invention is characterized in that the above-described color filter substrate and another substrate are arranged to face each other at a predetermined interval via a photo spacer, and a display medium is sandwiched between these substrates. Provided is a display device.

  According to the present invention, by controlling the thickness of the light shielding layer according to the thickness of the pixel coloring layer, it is possible to maintain a predetermined height of the photo spacer without adjusting the thickness of the coloring layer or the protruding layer. A color filter substrate and a method for manufacturing the same are provided. In addition, a display device including such a color filter substrate is provided.

  Hereinafter, embodiments of the present invention will be described.

  FIG. 1 is a sectional view showing one pixel of a color filter substrate for an MVA mode liquid crystal display device according to the first embodiment of the present invention. In FIG. 1, a light shielding layer 2 having a predetermined pattern is formed on a transparent substrate 1, and a red colored layer 3a, a green colored layer 3b, and a blue colored layer 3c are two-dimensionally arranged in a region divided by the light shielding layer 2. Is arranged. A transparent conductive film, for example, an ITO film 4 is formed on each of the colored layers 3a, 3b, and 3c, and a projection layer 5 having a predetermined pattern is formed on the transparent conductive film, thereby forming a color filter substrate. .

  In such a color filter substrate, the light shielding layer 2 has a spacer forming region 6 having a larger area than the other portions, and the red colored layer 3a and the green colored layer 3b are formed on the spacer forming region 6. When the blue colored layer 3c is formed two-dimensionally, the spacer red colored layer 7a, the spacer green colored layer 7b, and the spacer blue colored layer 7c are sequentially stacked three-dimensionally. On the spacer colored layers 7 a, 7 b and 7 c, a spacer projection layer 8 is laminated via the ITO film 4 simultaneously with the formation of the projection layer 5.

  In addition, since the spacer protrusion layer 8 is formed on the laminated body of spacer colored layers, it is a thin layer and covers the upper surface and side surfaces of the laminated body of colored layers.

  As described above, the spacer formation region 6 of the light shielding layer 2, the spacer coloring layers 7a, 7b and 7c, and the spacer protrusion layer 8 constitute a photo spacer.

  The photo spacer needs to be maintained at a predetermined height in order to perform its function, and the height Y is determined from the surface of the ITO film 4 on the colored layer 3a in FIG. It is represented by the distance to the surface. As a method of maintaining the height of the photo spacer at a predetermined value, it is conceivable to adjust the thickness of the spacer projection layer 8 which is the final laminated film. In such a case, the thickness of the projection layer 5 is designed. The value is deviated with respect to the value, resulting in problems such as a deterioration in viewing angle and a decrease in contrast.

As a result of repeated studies on the cause of the variation in the height of the photo spacer, the present inventors change the height of the photo spacer when the thickness of the pixel coloring layer is changed in order to adjust the color characteristics. I found out. Accordingly, the present inventors performed experiments for variously changing the thicknesses of the pixel coloring layers 3a, 3b, and 3c to obtain the amount of change in the height of the photo spacer, and obtained the results shown in Table 1 below. .

  The results of Table 1 are plotted with the horizontal axis indicating the thickness of the pixel coloring layers 3a, 3b, and 3c and the vertical axis indicating the amount of change ΔY in the height of the photo spacer. A straight line was obtained. This straight line can be expressed by the following approximate expression (1).

ΔY = 1.0998X−1.5398 (1)
The correlation coefficient R ² indicating the coincidence between the plotted points and the approximate expression was 0.9956.

  From the above results, when the thickness X of the pixel coloring layers 3a, 3b, and 3c is changed from 1.4 μm to 1.5 μm, for example, the height Y of the photo spacer may be increased by about 0.11 μm. is assumed.

  On the other hand, the inventors adjust the film thickness of the light shielding layer 2 in consideration of the change in the height Y of the photo spacer due to the variation in the thickness X of the pixel coloring layers 3a, 3b, 3c. The inventors have found that the desired photo spacer height Y can be maintained at a desired value.

That is, the present inventors obtained the results shown in Table 2 below when the relationship between the change amount ΔZ of the film thickness of the light shielding layer 2 and the change amount ΔY of the height of the photo spacer was obtained.

  The results shown in Table 2 are plotted with the amount of change ΔZ in the thickness of the light shielding layer 2 on the horizontal axis and the amount of change ΔY in the height of the photo spacer on the vertical axis. A straight line was obtained. This straight line can be expressed by the following approximate expression (2).

ΔY = 0.4996ΔZ + 0.0008 (2)
The correlation coefficient R ² indicating the coincidence between the plotted points and the approximate expression (2) was 0.9992.

  From FIG. 3 and the above equation (2), it can be seen that the change amount ΔZ of the thickness of the light shielding layer 2 and the change amount ΔY of the height of the photo spacer have a linear relationship with an inclination of 0.5.

  From the above, the amount of change ΔY in the height of the photo spacer when the thickness of the pixel coloring layers 3a, 3b, 3c is changed to X by the above equation (1) is obtained, and from the above equation (2). If the amount of change ΔZ in the thickness of the light shielding layer 2 corresponding to ΔY is obtained, and conversely, if the thickness of the light shielding layer 2 is decreased by ΔZ, ΔY is canceled and the photo spacer before the thickness X fluctuates The height of can be maintained.

  Therefore, as described above, when the thickness X of the pixel coloring layers 3a, 3b, and 3c is changed from 1.4 μm to 1.5 μm, it is assumed that the height Y of the photo spacer is increased by about 0.11 μm. However, in order to maintain this at the height Y of the photo spacer before the change of the thickness X, ΔY (= 0.11) / the slope of the straight line (≈0.5) = 0. The film thickness of the light shielding layer 2 may be reduced by 22 (μm).

  Thus, the desired height Y of the photospacer is maintained by setting the film thickness of the light shielding layer 2 from the amount of change in the film thickness of the light shielding layer 2 obtained by the above formulas (1) and (2). Is possible.

FIG. 3 is a cross-sectional view illustrating a configuration of a color filter substrate according to an embodiment of the present invention. The characteristic view which shows the relationship between the area X of a spacer formation area, and the variation | change_quantity (DELTA) Y of the height of a photo spacer. The characteristic view which shows the relationship between the variation | change_quantity (DELTA) Z of the film thickness of a light shielding layer, and the variation | change_quantity (DELTA) Y of the height of a photo spacer.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Transparent substrate, 2 ... Light-shielding layer, 3a ... Red colored layer, 3b ... Green colored layer, 3c ... Blue colored layer, 4 ... ITO film, 5 ... Projection layer, 6 ... Spacer formation area, 7a ... Spacer red colored layer , 7b ... spacer green colored layer, 7c ... blue colored layer, 8 ... spacer projection layer.

Claims (9)

Forming a light shielding layer of a predetermined pattern having a spacer formation region on the transparent substrate;
Arranging a plurality of color coloring layers in a two-dimensional manner in a region partitioned by the light shielding layer, and simultaneously laminating a plurality of color coloring layers in a three-dimensional manner on the spacer formation region of the light shielding layer;
Forming a transparent conductive film on the plurality of pixel coloring layers and the spacer coloring layer; and a predetermined pattern of protrusions on the transparent conductive film on the two-dimensionally arranged pixel coloring layers And simultaneously forming a layer, covering the transparent conductive film on the three-dimensionally laminated spacer colored layers with a spacer projection layer, and arranging the two-dimensionally arranged pixel colored layers Forming a photo spacer having a height Y from the upper surface of the upper transparent conductive film to the upper surface of the spacer protrusion layer, and obtaining the desired value of the height Y of the photo spacer. A method for producing a color filter substrate, wherein the thickness of the light shielding layer is controlled according to the thickness of the colored layer.   The thickness of the light shielding layer is controlled by calculating the amount of change in the height Y of the photo spacer that is assumed according to the thickness of the pixel coloring layer, and calculating the amount of change in the thickness of the light shielding layer from this amount of change. A method of manufacturing a color filter substrate, wherein the calculation is performed so as to cancel out the change amount of the height Y of the photo spacer based on the change amount of the film thickness. 3. The color filter substrate according to claim 2, wherein the amount of change ΔY in the height Y of the photo spacer is calculated by the following formula (1) based on the thickness X of the pixel coloring layer. Method.
ΔY = 1.0998X−1.5398 (1) The thickness of the light shielding layer is controlled by calculating the amount of change ΔZ in the thickness of the light shielding layer according to the following equation (2) from the amount of change ΔY in the height Y of the photo spacer calculated by the equation (1). The method for producing a color filter substrate according to claim 3, wherein the method is performed.
ΔY = 0.4996ΔZ + 0.0008 (2) Transparent substrate,
A light shielding layer of a predetermined pattern having a spacer formation region formed on the transparent substrate,
A plurality of pixel coloring layers arranged two-dimensionally in a region partitioned by the light shielding layer;
A plurality of colored spacer layers layered three-dimensionally on the spacer formation region of the light shielding layer;
A transparent conductive film formed on the pixel coloring layer and the spacer coloring layer of the plurality of colors;
A protrusion layer having a predetermined pattern disposed on the transparent conductive film on the pixel coloring layer, and a spacer protrusion layer disposed on the transparent conductive film on the spacer coloring layer,
A color filter substrate in which a photo spacer having a height Y from the upper surface of the transparent conductive film on the pixel coloring layer to the upper surface of the spacer protrusion layer is constituted by the spacer coloring layer, the transparent conductive film and the spacer protrusion layer. In
The color filter substrate, wherein the light shielding layer has a thickness controlled according to a thickness of the pixel coloring layer so as to obtain a desired value of the height Y of the photo spacer.   The light shielding layer calculates a change amount of the height Y of the photo spacer that is assumed according to the thickness of the pixel coloring layer, and calculates a change amount of the film thickness of the light shielding layer from the change amount. 6. The color filter substrate according to claim 5, wherein the color filter substrate has a thickness controlled so as to cancel the amount of change in the height Y of the photo spacer based on the amount of change in thickness. The color according to claim 6, wherein the calculation of the change amount ΔY of the height Y of the photospacer is performed by the following formula (1) based on the area X of the spacer formation region of the light shielding layer. Filter substrate.
ΔY = 3 × 10 ⁻⁹ X ² −2 × 10 ⁻⁵ X + 0.029 (1) The thickness of the light shielding layer is controlled by calculating the amount of change ΔZ in the thickness of the light shielding layer according to the following equation (2) from the amount of change ΔY in the height Y of the photo spacer calculated by the equation (1). The color filter substrate according to claim 7, wherein the color filter substrate is formed by:
ΔY = 0.4996ΔZ + 0.0008 (2)   The color filter substrate according to any one of claims 5 to 8 and another substrate are arranged to face each other at a predetermined interval via the photo spacer, and a display medium is sandwiched between the substrates. Display device.

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