JPH0815727A - Production of electrode substrate for liquid crystal display device - Google Patents

Abstract

PURPOSE:To improve the production yield for the method to form a color filter on a electrode substrate where a TFT is to be formed. CONSTITUTION:A color filter is formed on a supporting sheet to obtain a transfer sheet. Then color filters with pattern defects on the transfer sheet are rejected and only a good transfer sheet is transferred to an electrode substrate where a TFT is to be formed. Then an ITO film is formed and patterned into a specified pattern. An insulating film 11 is formed on the whole surface and a light-shielding film 12 is formed in a specified shape. Therefore, since the color filter is wholly transferred at one time from the preliminarily produced transfer sheet, the production yield of the TFT substrate is improved. Further, since the surface of the oriented film is finally made almost flat, the rubbing treatment of the oriented film is surely performed even when a more precise pattern is formed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing an electrode substrate in an active matrix type liquid crystal display device.

[0002]

2. Description of the Related Art As a typical conventional structure of an active matrix type liquid crystal display device, a light-shielding film and a color filter for concealing the electrodes and wiring of the TFT are provided in the TFT.
A structure formed on an electrode substrate facing the formation-side electrode substrate is widely adopted. However, since the bonding displacement between the two electrode substrates facing each other occurs, it is necessary to design the width of the light-shielding film to be large corresponding to the bonding accuracy, and therefore the area of the color filter becomes small and the aperture ratio becomes small. There was a problem of lowering. In order to solve this problem, for example, as disclosed in Japanese Patent Laid-Open No. 4-253028, a method of improving the aperture ratio by forming a color filter on the electrode substrate on the TFT formation side has been proposed.

[0003]

However, in the method of forming the color filter on the electrode substrate on the TFT formation side as described above, three colors of red (R), green (G) and blue (B) are used.
Since the patterning is performed in separate steps, the number of steps increases, the yield is likely to deteriorate, and the efficiency is not very good, for example, the TFT substrate formed with difficulty is not utilized. The present invention aims to remedy the above problems.

[0004]

Therefore, in the present invention, when manufacturing an electrode plate for a liquid crystal display device, three color filters of red (R), green (G) and blue (B) are provided on the support sheet 1. Then, after forming a transfer sheet, the non-defective color filter on the transfer sheet is transferred to the TFT formation side electrode substrate. It demonstrates in order along FIG. 1-FIG.

First, as shown in FIG. 1, a transfer sheet in which an RGB color filter coloring layer 3 is formed on a support sheet 1 via a release layer 2 is prepared. On the other hand, as shown in FIG. 2, T except the ITO film 10 which becomes the pixel electrode is formed on the glass substrate 8.
Form an FT circuit. In the figure, the opening 7 is where a color filter will be formed in the future. As shown in FIG. 3, a photocurable adhesive layer 9 is formed on the TFT-forming electrode substrate.
4, the transfer sheets are overlapped while controlling the position as shown in FIG. 4, and ultraviolet rays are irradiated from the TFT non-forming surface side of the TFT forming side electrode substrate to cure the adhesive layer 9 ′ in the opening 7. . At this time, the adhesive layer 9 on the TFT is not cured because it is not irradiated with light.

Next, as shown in FIG. 5, the support sheet 1 is peeled off together with the peeling layer 2 to form the color filter coloring layer 3, and then the uncured adhesive layer 9 on the thin film transistor and the wiring portion is formed as shown in FIG. Rinse with water. Next, the ITO film 10 is formed on the entire surface as shown in FIG. 7, and this is etched and patterned into a predetermined shape as shown in FIG. 8 to form the pixel electrode 13. At this time, electrical connection between the pixel electrode 13 and the drain electrode 5 of the TFT is achieved. Then, as shown in FIG. 9, an insulating film 11 is formed on the entire surface as needed, and a light-shielding film 12 covering at least the thin film transistor and the wiring portion is formed in a desired shape as shown in FIG. 10, preferably the surface is flattened. .

[0007]

The present invention has three functions of red (R), green (G) and blue (B).
Create a transfer sheet with color filters,
Since the color filter on the transfer sheet is transferred to the electrode substrate on which the TFT is formed, only defective products can be formed on the TFT forming substrate after removing the color filter having a defective shape in advance, and the yield of the TFT substrate can be improved.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a method of manufacturing an electrode substrate for a liquid crystal display device of the present invention will be described in detail below with reference to the drawings. FIG. 1 shows an example of a transfer sheet used in the present invention. A release layer 2 made of photo-cured polyvinyl alcohol is formed on the support sheet 1, and three colored layers 3R, 3G, 3B (hereinafter, simply referred to as the colored layer 3) are adjacent to each other on the release layer 2. A color filter layer arranged in a plane is formed.

The support sheet 1 may be made of a heat-resistant synthetic resin such as polyethylene terephthalate, polyimide or polycarbonate, or a nickel iron alloy, and its thickness is preferably in the range of 30 μm to 200 μm. Each of the colored layers 3R,
It is desirable to provide an alignment mark for alignment between the 3G and 3B or between the colored layer 3 and the electrode substrate on the TFT formation side. The peeling layer 2 is applied prior to the formation of the colored layer 3. It is formed on the part of the support sheet 1 which is not present by photolithography or laser light.

The release layer 2 made of photo-cured polyvinyl alcohol adheres well to the support sheet 1 and has good releasability from the colored layer 3. The thickness of the peeling layer 2 is 1 μm to 15 μm.
It is desirable that the surface smoothness is about μm and the surface smoothness is about 0.1 μm or less. The release layer 2 is formed by applying a mixture of polyvinyl alcohol and a photocrosslinking agent such as dichromate, chromate, or diazo compound evenly on the support sheet 1 and irradiating it with ultraviolet rays while heating. Let it harden.

A colored layer 3 is formed on the cured release layer 2. As a method of forming the colored layer 3, any of the conventionally known photolithography method, printing method, electrodeposition method and the like can be adopted. As the photolithography method, either a pigment dispersion method or a dyeing method can be adopted. In addition, it is preferable to finish the colored layer 3 in an inverse taper shape.
It is desirable since it becomes a forward taper after the transfer and prevents the pixel electrode from breaking.

A method for forming a color filter on the TFT formation side electrode substrate using the transfer sheet prepared as described above will be described below. Glass substrate 8 as shown in FIG.
At the stage where the gate electrode 6, the source electrode 4, and the drain electrode 5 were respectively formed thereon, an adhesive layer 9 was applied and formed on the entire surface of the TFT formation side electrode substrate as shown in FIG. As the adhesive, for example, an acrylate-based UV-curable resin similar to the pigment-dispersed resist used for the colored layer 3, except that the pigment component is removed, is applied to a thickness of about 3 μm with a bar coater and air-dried for 10 minutes. To form the adhesive layer 9.

As shown in FIG. 4, the transfer sheet was superposed on the TFT-forming side electrode substrate while aligning it, and while keeping this state, it was set on a hot plate of a roll press and preheated at 100 ° C. for 5 minutes. did. Then the temperature 100
Rolling was performed at a temperature of 5 ° C. and a pressure of 5 kg / cm ² , and ultraviolet rays were radiated from the TFT non-forming surface side to cure the adhesive in the opening 7 excluding the thin film transistor and the wiring portion to transfer the colored layer 3.

Next, the transfer sheet is removed, and the electrode substrate on the TFT formation side where the adhesive layer 9'is cured only in the opening 7 as shown in FIG. The adhesive layer 9 is flowed and the TFT surface appears. Here, as shown in FIG. 7, the ITO film 1
0 was vapor-deposited and formed on the entire surface by sputtering or the like, and this was etched and patterned into a predetermined shape as shown in FIG. 8 to form the pixel electrode 13 on the color filter (coloring layer 3). The pixel electrode 13 is electrically connected to the drain electrode 5.

Thereafter, as shown in FIG. 9, a SiO ₂ insulating film 11 having a thickness of about 0.1 μm is formed by vapor deposition, and then a light shielding film 12 is formed in a desired shape with an appropriate thickness as shown in FIG. did. By the above operation, the surface of the electrode substrate on which the TFT is formed is made substantially smooth, and the alignment film 14 can be formed flat as shown in FIG. 11, which enables accurate rubbing treatment.

[0016]

According to the present invention, since the respective colors of the colored layer 3 are not directly formed on the TFT substrate in order but are transferred and formed collectively from a transfer sheet prepared in advance, the yield of the TFT substrate can be improved. Moreover, the pixel electrode is simply connected to the drain electrode of the TFT without forming a through hole or the like. Moreover, since the surface of the alignment film is finally almost flattened, there is a merit that the rubbing treatment of the alignment film is surely performed even if the fineness is increased. The entire surface insulating film is provided to prevent a short circuit when the light shielding film is conductive, and can be omitted when the light shielding film is insulating.

[0017]

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing an example of a transfer sheet used in the present invention.

FIG. 2 is an explanatory view showing one embodiment of a method for manufacturing an electrode substrate for a liquid crystal display device of the present invention in the order of steps.

FIG. 3 is an explanatory view showing one embodiment of a method for manufacturing an electrode substrate for a liquid crystal display device of the present invention in the order of steps.

FIG. 4 is an explanatory view showing one embodiment of a method of manufacturing an electrode substrate for a liquid crystal display device of the present invention in the order of steps.

FIG. 5 is an explanatory view showing one embodiment of a method for manufacturing an electrode substrate for a liquid crystal display device of the present invention in the order of steps.

FIG. 6 is an explanatory view showing one embodiment of a method of manufacturing an electrode substrate for a liquid crystal display device of the present invention in the order of steps.

FIG. 7 is an explanatory view showing one embodiment of a method for manufacturing an electrode substrate for a liquid crystal display device of the present invention in the order of steps.

FIG. 8 is an explanatory view showing an embodiment of a method of manufacturing an electrode substrate for a liquid crystal display device of the present invention in the order of steps.

FIG. 9 is an explanatory view showing one embodiment of a method for manufacturing an electrode substrate for a liquid crystal display device of the present invention in the order of steps.

FIG. 10 is an explanatory view showing one embodiment of a method for manufacturing an electrode substrate for a liquid crystal display device of the present invention in the order of steps.

FIG. 11 is an explanatory view showing an example of a method of manufacturing an electrode substrate for a liquid crystal display device of the present invention in the order of steps.

[Explanation of symbols]

 1 Support Sheet 2 Release Layer 3 (3R, 3G, 3B) Colored Layer 4 Source Electrode 5 Drain Electrode 6 Gate Electrode 7 Opening 8 Glass Substrate 9, 9'Adhesive Layer 10 ITO Film 11 Insulating Film 12 Light-Shielding Film 13 Pixel Electrode 14 Alignment film

Claims (2)

[Claims] 1. In a manufacturing process of an active matrix type liquid crystal display device, a color filter on a transfer sheet is attached to a TFT formation side electrode substrate on which a thin film transistor other than a pixel electrode and a wiring portion are formed by using an ultraviolet curable adhesive. Then, the adhesive on the opening is cured by irradiating ultraviolet rays from the side where the TFT is not formed, the support sheet is peeled off, the color filter is transferred, and the uncured adhesive on the thin film transistor and the wiring part is removed, and then the entire surface. A liquid crystal, characterized in that an ITO film is formed on a substrate and patterned into a predetermined shape to form a pixel electrode connected to a drain electrode, and then a light-shielding film that covers at least the thin film transistor and the wiring portion is formed in a desired shape. Manufacturing method of electrode substrate for display device. 2. The method for manufacturing an electrode substrate for a liquid crystal display device according to claim 1, wherein a light shielding film is formed on the TFT and the ITO film with an insulating film interposed therebetween.