JPH0419781A - Counter electrode substrate for liquid crystal display device - Google Patents

Abstract

(57) [Abstract] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a counter electrode substrate for a liquid crystal display device used for, for example, a color filter for a TPT-driven liquid crystal flat display.

[Prior Art] FIG. 7 is a cross-sectional view of a conventional counter electrode substrate for a liquid crystal display device disclosed in, for example, Japanese Patent Laid-Open No. 59-10988. In the figure, (1) is a substrate made of glass or the like; (2) is a colored layer, (21) is a light shielding film, (5) is a transparent conductive film, (8
1) is an insulating film, and (7) is an alignment treated film.

That is, a colored layer (2) is formed on a glass substrate (1) by a commonly used screen printing method, and the colored layer (2) is made of, for example, polyimide in which a pigment is dispersed. (2) By vacuum evaporation method etc.
A transparent conductive film (5) such as an ITO (Indium-Tin-Oxide) film is formed, and an insulating film (61) such as silicon chloride is formed on this transparent conductive film (5) by sputtering or the like. Then, an alignment film (7) made of acrylic resin or the like is formed on this insulating film (61) to obtain a counter electrode substrate for a liquid crystal display device.

[Problems to be Solved by the Invention] Since the conventional counter electrode substrate for a liquid crystal display device is configured as described above, the voltage application electrode of the liquid crystal display is only a transparent conductive film (5). Membrane (5)
Since the conductivity of the liquid crystal display is low, as the size of the liquid crystal display becomes larger, the voltage becomes non-uniform within one plane. Also, transparent conductive film (5)
Although it is necessary to have high transparency, there are problems in that improving transparency and improving conductivity are contradictory film qualities, making it difficult to improve transparency.

This invention was made to solve these problems, and it is possible to easily equalize the applied voltage within the liquid crystal display, improve the transparency of the transparent conductive film, and improve the display characteristics of the liquid crystal display device. The purpose is to obtain a counter electrode substrate for devices.

[Means for Solving the Problems] The counter electrode substrate for a liquid crystal display device of the present invention includes a substrate, a transparent conductive film provided on the substrate, and at least one of the substrate side and the opposite side of the transparent conductive film, The device includes a conductive film having a conductivity higher than that of the transparent conductive film and electrically connected to the transparent conductive film.

[Function] In this invention, by forming a conductive film at the above position, it is possible to lower the resistance of the electrode for voltage application, improve the transparency of the transparent conductive film, and improve the display characteristics of the liquid crystal display device. It can be done well.

[Example 1] Figure 1 is a new view of a counter electrode substrate for a liquid crystal display device according to an embodiment of the present invention. (21) is a light-shielding film; (3) is an organic insulating film made of a high-purity acrylic resin film formed by a printing method; (4) (5) is a conductive film formed of a Cr film processed into a desired pattern using, for example, a photolithography method, and (5) is an ITO (Indium-
Transparent conductive film formed of (Tin-Oxide) film, (6
) is an inorganic insulating film made of, for example, a silicon oxide film formed by a sputtering method, and (7) is an alignment film made of a polyimide film formed by, for example, a transfer method.

Hereinafter, an example of manufacturing a counter electrode substrate for a liquid crystal display device according to an embodiment of the present invention will be described based on the above drawings. That is, on a Pyrex glass substrate (1), for example, a light-shielding film (two films) of a polyimide film in which black pigment is dispersed is formed to a thickness of 0.5 to 3 μm by a printing method, and then a red, blue or green film is formed. A colored layer (2), which is a pixel display portion, is formed of a polyimide film in which pigment is dispersed. After that, a layer of 0.5 to 5 μm in thickness is printed on the colored layer (2), for example, by a printing method.
An organic insulating film (3) of a high purity acrylic resin film is formed so as to have the following properties. This acrylic resin film (3) is preferably thickened in order to enhance the effect of suppressing impurities in the colored layer (2) and improve the coverage of the transparent conductive film (5). For example, by sputtering, a thickness of 0.0
A conductive film (4) of Cr film is formed to have a thickness of 5 to 0.3 μI, and this Cr film (4) is processed into a desired pattern using, for example, photolithography. Although it is better for this pattern to be wider in order to improve conductivity, it is preferable to use the same pattern as the light-shielding film in order to prevent a decrease in the aperture ratio of the liquid crystal display.

Next, a transparent conductive film of ITO (Indium-Ti) is deposited on the patterned conductive film (4) of the Cr film to a thickness of 0.03 to 0.3 μm by sputtering or the like.
n-Oxide) film (5) is formed, and this ITO film (5) is formed.
), an inorganic insulating film (6) of a silicon oxide film is formed to a thickness of 0.01 to 1 μm by, for example, a sputtering method, and an inorganic insulating film (6) of a silicon oxide film (6) is formed by a transfer method, for example, to a thickness of 0.01 to 1 μm.
．． A polyimide film (7), which is an alignment-treated film, is formed so as to have a thickness of 0.03 to 0.1 μI to obtain a counter electrode substrate for a liquid crystal display device.

In addition, in the above embodiment, y! A conductive film (4) processed into a desired pattern is formed under the electrical film in the Meimei chamber, but the second
Even if a conductive film (4) is formed on a transparent conductive film (5) as shown in the cross-sectional view of a counter electrode substrate for a liquid crystal display device according to another embodiment of the present invention, the present invention shown in FIG. A conductive film (4) may be formed above and below a transparent conductive film (5) as shown in the cross-sectional view of a counter electrode substrate for a liquid crystal display device in another embodiment.

In the above example, a Pyrex glass substrate was used as the substrate (1), but a thin glass substrate such as a low-alkali glass substrate may also be used.Although a polyimide film with pigment dispersed therein was used as the colored layer (2), it was not possible to dye it. Other colored layers such as a gelatin film may also be used. In particular, the four-light part (21) is formed by the Sakae method or other method, and is patterned by a photolithography method.
A metal film such as a film may also be used.

Further, when the pattern of the conductive film (4) is formed in the same pattern as the light shielding film (21), the cross section of the counter electrode substrate for a liquid crystal display device according to another embodiment of the present invention shown in FIGS. 4 and 5. As shown in the figure, it is not necessary to form the 5 light shielding film (21).

In addition, although a printing method was used to form the colored layer (2), it is also possible to form the organic insulating film (
Although a printing method was used to form 3), a spin coating method may also be used.Although a Cr film was used as the patterned conductive film (4), it has a higher conductivity than ITO, which is the transparent conductive film (5). As long as the transparent conductive film (5) is large, it does not matter what material it is made of.Although the sputtering method was used for its formation, other methods such as vacuum evaporation may also be used.
-Tin-Oxide) film was used, but 5n02, I
Other transparent conductive films such as n2O3 may be used, and sputtering was used as the formation method, but other methods such as vacuum evaporation may also be used. Silicon oxide was used as the inorganic insulating film (6); however,
It may be made of silicon perfluoride, etc., and although the sputtering method was used to form it, other methods such as CVD may also be used.Also, this insulating film (6) does not need to be formed, and the alignment treatment film (7) may be used. Although a polyimide film was used, a film of polyvinyl alcohol or the like may also be used.Although a transfer method was used for the formation method, ordinary photolithography etc. may also be used.Also, the alignment film (7) may be formed using an oblique method of vacuum evaporation. A silicon oxide film formed by vapor deposition may also be used.

In addition, the light-shielding film (21) may be formed of a conductive Cr film (4) as shown in FIG. 5, which is a cross-sectional view of a counter electrode substrate for a liquid crystal display device according to another embodiment of the present invention; however, in this case, It is necessary to pattern the organic insulating film (3) in order to bring the Cr film (4) and the transparent conductive film (5) into contact.

[Effects of the Invention] As explained above, the present invention provides a substrate, a transparent conductive film provided on the substrate, and a conductivity of the transparent conductive film on at least one of the substrate side and the opposite side of the transparent conductive film. By using a conductive film that has a higher conductivity and is electrically connected to the transparent conductive film described above, it is possible to easily equalize the voltage applied within the liquid crystal display, and also to increase the transparency of the transparent conductive film. It is possible to obtain a counter electrode substrate for a liquid crystal display device, which has improved properties and display characteristics of the liquid crystal display device.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a counter electrode substrate for a liquid crystal display device according to an embodiment of the present invention, and FIGS. 2 to 6 are sectional views of a counter electrode substrate for a liquid crystal display device according to other embodiments of the invention. 7
The figure is a sectional view of a conventional counter electrode substrate for a liquid crystal display device. In the figure, (1) is a substrate, (4) is a conductive film, and (5) is a transparent conductive film. Note that the same reference numerals in each figure indicate the same or corresponding parts.

Claims (1)

[Claims] A substrate, a transparent conductive film provided on this substrate, and at least one of the substrate side and the opposite side of this transparent conductive film have a conductivity higher than that of the transparent conductive film, and have an electrical conductivity that is higher than the conductivity of the transparent conductive film. A counter electrode substrate for a liquid crystal display device, which is provided with a conductive film that is electrically connected.