JP2767557B2 - Method for manufacturing substrate with color filter for liquid crystal display device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a substrate with a color filter for a liquid crystal display device, in which two layers of sheet-like electrodes having a color filter interposed are formed on the inner surface of a substrate constituting a liquid crystal cell. It is about.

[0002]

2. Description of the Related Art In a simple matrix driving type liquid crystal color display device, it is necessary to provide a sheet-like transparent electrode for driving a liquid crystal on a color filter in order to improve display performance. Further, in order to increase the duty ratio for driving the liquid crystal, it is necessary to reduce the sheet resistance of the transparent electrode as much as possible.

In order to satisfy the above requirements, for example, as shown in FIG. 8, it has been proposed to sandwich a color filter between sheet-like electrodes having a two-layer structure and to connect them through a contact hole.

That is, first, a first sheet-like transparent electrode 1a is formed on a glass substrate (not shown) (FIG. 8A), and a resist 3 for forming a contact hole is provided thereon (FIG. 8A). 8 (b)). After the color filter 4 is formed thereon (FIG. 8C), the resist 3 is removed to form a contact hole 5 (FIG. 8D). Next, a second-layer sheet-shaped transparent electrode 1b is formed from above (FIG. 8E).

In the liquid crystal cell having the above structure,
The transparent electrode 1b on the upper part of the color filter 4 is electrically connected to the lower transparent electrode 1a via the contact hole 5, and has a configuration in which two layers of transparent electrodes 1a and 1b are connected in parallel. Even if the sheet resistance of the upper transparent electrode 1b is not reduced, the apparent resistance is reduced by using an ITO film or the like having a lower resistance for the lower transparent electrode 1a. Can be.

[0006]

However, in the substrate with a color filter for a liquid crystal display device manufactured as described above, as shown in part A of FIG. Part may occur,
In this case, the two layers of the transparent electrodes 1a and 1b have a poor connection, and an appropriate drive voltage is not transmitted to the transparent electrode 1b on the upper side of the two electrodes. As a result, an unlit portion is generated in the display unit. There is.

That is, in the above-described manufacturing method, the contact hole 5 is formed by forming a hole in the resist 3 when the color filter 4 is formed by electrodeposition. As shown in FIG. 8, the color filter 4 has an inverted slope shape.
When an ITO film or the like to be the transparent electrode 1b is formed thereon by sputtering, film formation inside the contact hole 5 is not sufficiently performed, and a connection failure occurs as described above.

The present invention has been made in view of the above-mentioned problems, and is intended to provide a reliable connection between two layers of sheet-like electrodes, and to prevent the occurrence of unlit pixels in a liquid crystal display device. An object of the present invention is to provide a method for manufacturing a substrate with a color filter.

[0009]

According to the present invention, there is provided a method of manufacturing a substrate with a color filter for a liquid crystal display device, comprising a two-layer sheet-like structure having a color filter interposed on an inner surface of a substrate constituting a liquid crystal cell. In the method of manufacturing a substrate with a color filter for forming an electrode, a first sheet-like electrode formed on the substrate is provided with a through hole, and a resist for forming a contact hole is formed so as to cover a part of the through hole. After forming a color filter thereon, the resist is removed to form a contact hole, a second sheet-like electrode is further formed thereon, and the first sheet electrode is formed through the contact hole. The second sheet-shaped electrode is connected to the second sheet-shaped electrode.

[0010]

In the method of manufacturing a substrate with a color filter for a liquid crystal display device according to the present invention, a resist for forming a contact hole is formed so as to cover a part of a through hole provided in a first sheet-like electrode on the substrate. Is provided, when the color filter is formed, its cross-sectional shape becomes a slope shape, and the second sheet-like electrode formed on the upper side thereof is securely connected to the first sheet-like electrode.

[0011]

FIG. 1 is a perspective view showing an embodiment of the present invention. The same reference numerals as in FIG. 8 denote the same components. 2 to 7 show various examples of the contact hole structure, in which (a) is a plan view, (b) is a longitudinal sectional view, and (c) is a transverse sectional view.

In this embodiment, when the contact hole 5 for connecting the two layers of transparent electrodes 1a and 1b sandwiching the color filter 4 is formed, its cross-sectional shape is made into a slope shape, and the two-layer transparent electrode is formed. This ensures the connection between 1a and 1b. Specifically, as shown in part B of FIG. 2C, when the color filter 4 is formed on the ITO stripe pattern (transparent electrode 1a) by the electrodeposition method, the color filter 4 is formed in the pattern end face direction. It is known that 4 protrudes, and this is based on the fact that the cross section of this portion becomes slope-shaped.

It is an important point of this embodiment that a slit-shaped color filter section is formed inside the contact hole by providing a slit-shaped hole in the first-layer transparent electrode using the above principle. I have. Hereinafter, FIG.
The process of forming a new contact hole will be described.

FIG. 1A shows a glass substrate (not shown) on which an ITO film having a sheet resistance of about 10 Ω / cm ² is formed as a first sheet-like transparent electrode 1a by a photolithographic method. Is patterned. At this time, the photomask is designed so that a through hole (slit-like hole) 2 having a width of about 20 μm is formed in a portion corresponding to a space portion of the opposing pattern.

In FIG. 1B, a resist 3 for forming a contact hole is formed by photolithography so as to cover a part of the through hole 2. Here, it is formed so as to straddle one side of the through hole 2.

FIG. 1 (c) A color filter 4 is formed by an electrodeposition method with the above-mentioned resist 3 for forming a contact hole. At this time, the cross section on the opposite side of the through hole 2 without the resist 3 has a gentle slope shape with the color filter 4 protruding as shown in the figure.

After the color filter 4 is fully baked at 250.degree. C. for 2 hours, the resist 3 is removed with a possible soda to form a contact hole 5. FIG. Thereby, a portion where the first transparent electrode 1a from below the color filter 4 is exposed is formed.

In FIG. 1E, an ITO film to be the second sheet-like transparent electrode 1b is formed on the color filter 4 by a sputtering method. At this time, the first-layer transparent electrode 1a and the second-layer transparent electrode 1b that are exposed from under the color filter 4 are connected through the upper surface of the color filter 4 having a sloped cross section.

Thereafter, the second-layer transparent electrode 1b is patterned in a stripe shape by photolithography so as to be parallel to the first-layer transparent electrode 1a, thereby completing the formation of the contact hole 5 in this embodiment.

In this manner, by connecting the first-layer transparent electrode 1a and the second-layer transparent electrode 1b through the contact hole 5, the connection between the two-layer transparent electrodes 1a and 1b is ensured. Become. Therefore, it is possible to stably manufacture a simple matrix type liquid crystal display device that does not generate unlit pixels.

Although the structure of the contact hole 5 is shown in FIGS. 2 to 7, the color filter 4 is actually used.
Is about 1 μm, and the lateral width of the slope portion of the color filter 4 is about 5 μm. That is,
This portion has a gentle slope with an aspect ratio of 1: 5.

In the method shown in the conventional example, the connection between the two-layered electrodes 1a and 1b is performed by using the back side (reverse slope-shaped portion) of the slope-shaped portion. Outbreaks cannot be completely prevented. In the conventional method, when the thickness of the color filter 4 exceeds the height of the resist 3 for forming a contact hole, the removal of the resist 3 becomes insufficient. An opening will be provided. However, this method has a problem that it is very weak to side etching when patterning the second-layer transparent electrode 1b.

In the present invention, for example, by adopting the structure shown in FIG. 2, FIG. 3, FIG. 5, and FIG. 7, the opening is inevitably inside the upper part of the pattern, and it becomes possible to make the structure resistant to side etching. . Further, by adopting the structure shown in FIGS. 2 to 5 and FIG. 7, even if a connection failure occurs in some of the contact holes 5, the drive voltage can be transmitted through another adjacent contact hole 5 adjacent thereto. This makes it possible to more completely prevent the occurrence of unlit pixels.

FIG. 2 shows an example in which a resist 3 is provided so as to straddle one side of a slit-like through hole 2 as in FIG. 1 to form a contact hole 5, and FIG. FIG. 4 shows an example in which a contact hole 5 is formed so as to cover both sides of the hole 2, and FIG. 4 shows an example in which a resist 3 is provided outside the two semicircular through holes 2 to form the contact hole 5. I have.

FIG. 5 shows an example in which a resist 3 is provided so as to cover both sides at the center of a slit-shaped through hole 2 to form a contact hole 5, and FIG. FIG. 7 shows an example in which two resists 3 are provided on the outside to form a contact hole 5, and FIG. Is shown.

[0026]

As described above, according to the present invention, a contact hole is formed by providing a resist over a part of a through-hole provided in a first sheet-like electrode. When a is formed, the cross-sectional shape becomes a slope shape, the connection between the two layers of sheet-like electrodes is ensured, and it is possible to stably manufacture a liquid crystal display device in which no unlit pixels are generated. It has the effect of becoming.

[Brief description of the drawings]

FIG. 1 is a perspective view showing one embodiment of the present invention.

FIG. 2 is an explanatory view showing another example of the structure of a contact hole.

FIG. 3 is an explanatory view showing another example of the structure of a contact hole.

FIG. 4 is an explanatory view showing another example of the structure of a contact hole.

FIG. 5 is an explanatory view showing another example of the structure of a contact hole.

FIG. 6 is an explanatory view showing another example of the structure of the contact hole.

FIG. 7 is an explanatory view showing another example of the structure of the contact hole.

FIG. 8 is a perspective view showing a conventional example.

[Explanation of symbols]

 1a Transparent electrode 1b Transparent electrode 2 Through hole 3 Resist 4 Color filter 5 Contact hole

Claims (1)

(57) [Claims] 1. A method of manufacturing a substrate with a color filter in which two layers of sheet-like electrodes having a color filter interposed therein are formed on an inner surface of a substrate constituting a liquid crystal cell. A through hole is provided in the sheet-like electrode of the above, a resist for forming a contact hole is formed so as to cover a part of the through hole, a color filter is formed thereon, and then the resist is removed to form a contact. Forming a hole, further forming a second sheet-like electrode thereon, and connecting the first sheet-like electrode and the second sheet-like electrode through the contact hole. A method for manufacturing a substrate with a color filter for a liquid crystal display device.