JPS62240930A - Manufacture of liquid crystal display panel - Google Patents

Abstract

PURPOSE:To equalize a gap size by leaving a photosensitive resin pattern as a gap holding spacer, on a film thickness conductive transparent electrode pattern layer, using a conductive transparent electrode film substrate as a common electrode use transparent substrate, and injecting and sealing a liquid crystal between said substrate and a main substrate. CONSTITUTION:An ITO film 60 of a transparent opposed common electrode material is stuck to the whole surface of a main surface 15 of an opposed common electrode use transparent substrate 7, and on this film, a photoengraving processing photoresist 16 is formed, and by using it as a mask, the film thickness of the ITO film 60 of a part which becomes a picture element area part 17 is decreased selectively, and said film is hardened and left on a layer of the remaining ITO film 62 whose film thickness is thick. The ITO films 61, 62 having each different film thickness and the common electrode use transparent substrate 7 which has formed a spacer are placed and pressed against on a transparent main substrate 5 so that each main surface is opposed, and also, relative positions of a scanning signal line pattern 3 of the transparent main substrate 5 and the thick film layer 62 of the common electrode use transparent substrate 6 conform with each other, a gap part 9 is formed by sticking and fixing both the substrates 5, 7 and a liquid crystal 10 is injected and sealed into this gap part 9. In this way, the uniformity of the gap can be held and improved.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a liquid crystal display panel (hereinafter abbreviated as "LCD panel"), particularly to a method for manufacturing a large IJ-Fuchs type LCD display panel using active materials such as TFT. It is something.

As shown in FIGS. 3 and 4, an active matrix type LCD panel using conventional technology TPT or the like has a transparent pixel electrode 1 on the main surface and a control element 2 such as TPT that controls the pixel electrode 1. Furthermore, a transparent main substrate 5 made of glass or the like has a scanning signal line pattern 3 for selectively interlocking the control element group and an image signal line pattern 4, and a transparent conductive film is formed on the entire main surface of the transparent substrate such as glass. Transparent substrates 7 for common electrodes coated with so-called ITOli 16 are arranged close to each other at intervals of 2 to 10 Itm (varies depending on the LCD panel configuration) via spacers 8 made of glass beads, etc., and the gap between both substrates 6.7 is This is obtained by injecting and sealing the liquid crystal 1o into the portion 9. In FIG. 4, 11 and 12 are external lead-out electrode terminal portions of the scanning signal line pattern 3 and image signal line pattern 4, respectively, 13 is a liquid crystal sealing portion, and 14 is a portion of the transparent substrate 7 for the common electrode. ITOTeO2 substrate 6
This is an electrode for connection with.

Problems to be Solved by the Invention L c D The transparent counter common electrode used in the panel is generally made of ITOTeO2 as a transparent conductive electrode thin film on the transparent substrate γ as described above.
In consideration of permeability, it is preferable to form the film thinly, and it is usually formed with a film thickness of about 100 to 1000 ohms, and its sheet resistance is about several 10 to several 100 Ω/hole. Moreover, the connection electrode portion with the ITOTeO 2-part circuit, which is the opposing common 7u pole, is often provided at a corner such as a corner portion of the panel due to the structure of the LCD panel. (Fig. 4) If the size of the LCD panel is small, even if the opposing common electrode is configured in the manner described above, the influence of the spreading resistance within the ITO film 6 will not cause any practical problems. As the size of the TO film 6 increases, the spreading resistance within the TO film 6 becomes a factor that adversely affects image quality.

That is, the membrane resistance is different in the vicinity of the external circuit connection electrode part and the part farthest from the corner, and when the ITO film 6 is used as a common electrode, a difference occurs in the potential within the film surface, and the This causes differences in the display characteristics of each unit pixel portion, which poses a problem in providing an LCD panel with uniform pixel images.

As a means to solve this problem, ITOTeO2
- It is possible to lower the resistance. However, in order to lower the sheet resistance, it is necessary to take measures such as increasing the ITOTeO2 thickness or changing the ITOTeO2 formation, that is, the film quality.
2. Since the transmittance is lowered, one of the functions as a transparent conductive film is impaired.

Furthermore, another problem associated with the increase in size of LCD panels is maintaining the gap accuracy at the portion where liquid crystal is injected. That is, to adjust the size of the gap between the main substrate 6 and the transparent substrate 7 for the opposing common electrode, spacers 8 such as glass beads are scattered in the gap, and the gap between the substrates 5 and 7 is maintained and adjusted using the same spacer diameter. method is commonly used. The key in this case is to uniformly distribute the spacers over the entire surface of the substrate, but as the substrate size increases, it is difficult to maintain uniformity in the distribution, resulting in non-uniformity in the gap size.

Means for Solving the Problem In order to solve this problem, the present invention provides a method in which the ITO film of the opposing common electrode located in the light transmitting region is formed to be thin.
The ITOg layer in the non-transparent region is formed thickly to reduce the resistance.By forming the opposing common electrode using a manufacturing method with a so-called two-layer structure, the sheet resistance within the ITO film is reduced.
By using the mask material used in the process of forming a thick ITO film layer in the non-transparent region as a spacer material for maintaining the gap size, it is possible to maintain a uniform gap size even when the substrate size is increased. The planar shape of the selectively formed low resistance ITO layer and spacer mask material is as follows:
It is formed in the same shape as the scanning signal line pattern 3 or the image signal line pattern 4 formed on the main substrate S of the LCD panel.

The transparent ITO film for the counter common electrode manufactured by this manufacturing method has a thin layer I with emphasis on transmittance in the pixel display area, that is, the light-transmitting part.
The TO film has a thick I film with emphasis on conductivity in the non-light-transmitting areas.
Since it has a structure in which a TO film is formed, it is possible to lower the sheet resistance of the entire opposing common electrode and not to reduce the transmittance of the light-transmitting region, in other words, it is possible to provide a transmissive LCD panel with low loss. Since the gap maintaining spacer is formed over the entire substrate in a predetermined size and shape by a pattern forming method, it is possible to maintain a uniform gap size over the entire panel surface.

Embodiment FIG. 1 is an enlarged partial cross-sectional view showing the completed cross-sectional structure of an LCD panel constructed by the manufacturing method of the present invention. Also,
FIGS. 2A to 2C are enlarged cross-sectional diagrams showing a method of manufacturing a common electrode having a spacer function according to the present invention. Note that the dimensions of the drawings are arbitrarily enlarged for convenience of drawing and explanation.

The details will be explained below with reference to the drawings. Note that in FIGS. 1 and 2, the same parts as in the conventional example are given the same numbers. First, the second
As shown in the figure, hundreds of ITO films 60 are coated as a transparent counter common electrode material on the entire main surface 15 of the transparent substrate 7 for the counter common electrode.
Deposit with a film thickness of 0 Å or more. Next, on this ITO film 6 film, a photoresist for true etching treatment is applied to a thickness of several μm to '+ottm.
Formed with a film thickness of The setting of the film thickness of the photoresist at this time will be described later, but the formation method is the spin code method using liquid photoresist when the film thickness is 2 to 37 tm or less, and the spin code method using liquid photoresist when the film thickness is thick. Although a film-like photoresist corresponding to the film thickness is used, the forming method is not limited to this, and any method that can form a film with a predetermined thickness may be used.

Next, a photomask used to form patterns for the functional elements 2, control wiring, etc. on the main substrate 6 as described in FIG. When the pattern pitch of the photoresist film is determined using a photomask, it has a cross-sectional shape as shown in FIG. 2B, and the pattern width Wm and pattern pitch Pm are the pattern width W of the running signal line pattern 3
A striped photoresist pattern 16 equal to p and pattern pitch Pp is formed on the ITO film 6o (
The cross-sections in FIGS. 2B and 2C are enlarged schematic views of portions corresponding to the man-to-man' section in FIG. ).

Note that the striped photoresist pattern 16 may be formed using a photomask for forming the image signal line pattern 4 on the main substrate 5.

Using this photoresist pattern 16 as a mask, FIG.
As shown in FIG.
The thickness of the TO film 60 is selectively reduced, and the ITO
After forming the film into a thin ITO film layer 61 with a thickness of 1000 Å or less, the photoresist pattern 16 used as a mask is subjected to heat treatment or electron beam irradiation treatment to form the remaining thick ITO film 6 and two layers. Leave the top up.

Note that the thickness of the photoresist formed on the ITO film eo is set as follows. For example, the gap (cell gear 7) 9 in the liquid crystal injection part of the LCD panel is 6 μm, the thickness of the thin ITO film 61 in the pixel area 17 is 600, and the thickness of the remaining thick ITO film 62 is 1 μm. If so, a film thickness of 5 lt+α is set at the time of deposition, taking into account shrinkage during curing, so that the film thickness of the photoresist after residual curing is approximately 51 t.

ITO films 61 with different film thicknesses manufactured as described above.
A common electrode transparent substrate 7 on which a spacer made of 62 and a hardened photoresist 16 is formed is placed so that its main surfaces face each other on a transparent main substrate 5 on which functional elements 2 and others are formed on its main surface, as shown in FIG. And if the scanning signal line pattern 3 of the transparent main substrate 6 and the thick film layer ITO film 62 of the common electrode transparent substrate 7 are placed and pressed so that their relative positions match, and the two substrates 6 and 7 are fixed with adhesive, A thick film layer of ITO [
62 and a spacer made of a photoresist pattern 16, a gap 9 is formed, and a liquid crystal 10 is formed in this gap 9.
An LCD panel is obtained by injection sealing.

Effects of the Invention In the conventional transparent counter common electrode made only of a thin ITO film, the electrode resistance increases as the substrate becomes larger due to the sheet resistance of the thin ITO film. In an LCD panel using a facing common electrode substrate,
As shown in FIG. 1, the ITO film 6 of the transparent counter common electrode of the pixel area 17 that controls the light 18 from the light source (not shown) is placed on the ITO film 6 to reduce the loss due to absorption of transmitted light in the circuit. control element section, scanning signal line pattern 3
By forming a thick layer on the ITO film 6 at the portion facing the non-light-transmitting region 19 formed by the above-described materials, a low-resistance layer is formed, so that the aperture ratio and transmittance of the pixel region 17 are not impaired. Therefore, the sheet resistance of the substrate can be lowered, and there is an effect of suppressing the deterioration of image quality due to the increase in spreading resistance and the non-uniformity of the potential distribution.

Furthermore, in order to maintain the uniformity of the cell gap as LCD panels increase in size, the photoresist pattern used in the two-layer ITO film formation process is hardened and used as a spacer, resulting in a uniform cell gap across the entire panel. Since spacers can be arranged, the effect of maintaining and improving the uniformity of the gap is also large.

[Brief explanation of drawings]

FIG. 1 is an enlarged schematic cross-sectional view of a completed LCD panel according to the manufacturing method of the present invention, FIG. An enlarged schematic cross-sectional view of an LCD panel according to an example, FIG.
FIG. 7 is a schematic plan view showing an example of the cross-sectional shape of the main board of the D panel. 1... Pixel electrode, 2... Control element such as TFT, 3... Scanning signal line pattern, 4...
...Image signal line pattern, 6...Transparent main substrate, θ, 60...Transparent conductive film (ITO film), 6
DESCRIPTION OF SYMBOLS 1... Thin film layer ITO film, 62... Residual thick film layer ITO film, 7... Transparent substrate for opposing common electrode, 8... Spacer, 9... ...Gap part, 1
o...Liquid crystal, 11...Set meal signal pattern drawer' electrode terminal part, 12...Image signal pattern drawer electrode terminal part, 13...Liquid crystal sealing Department,
14...Terminal part for external connection of opposing common electrode, 1
5... Main surface of transparent substrate 7 for opposing common electrode, 16
...Photoresist pattern, 17...
Light-transmitting area, ie, pixel area, 18... Light emitted from the light source, 19... Non-light-transmitting area. Name of agent: Patent attorney Toshio Nakao and 1 other person/-
- Self-confessed plagiarism J - One all signal pattern 5 - Yumeishu Motohiro b no, ] 1 greeting @ I TOR 62 - Kokusai shoulder layer ITO shoes 71 - Touaien 1kou V stamp False extraction'y-rW1 Jiruki Kip 7 pairs of congratulatory eyebrows transparent men's spoons 6 no.

Claims (3)

[Claims] (1) A thin film layer with a thickness of 1000 Å or less on a transparent substrate,
A two-layer conductive transparent electrode film consisting of a thick film layer with a film thickness of several thousand angstroms or more is formed in a striped pattern, and a photoresist for pattern formation is formed on this conductive transparent electrode film pattern layer. (Photosensitive resin) pattern is left as a spacer for maintaining a gap, and this conductive transparent electrode film substrate is used as a transparent substrate for an opposing common electrode, and liquid crystal is injected and sealed between it and the main substrate. Manufacturing method for liquid crystal display panels. (2) Thickness of the striped pattern provided on the common electrode transparent substrate The conductive transparent electrode film and the remaining photoresist pattern on the same film are formed to have the same dimensions and shape as the control wiring pattern on the main board. Place the common electrode transparent substrate pattern so that it matches the control wiring pattern on the main substrate,
2. The method of manufacturing a liquid crystal display panel according to claim 1, further comprising injecting and sealing liquid crystal into the gap between the two substrates formed by the pattern. (3) A control wiring pattern in which a conductive transparent electrode film with a thickness of several thousand angstroms or more is deposited over the entire main surface of the common electrode transparent substrate, a photoresist is deposited on the conductive transparent electrode film, and the photoresist is formed on the main substrate. A photoresist pattern is formed using a forming photomask, and using the photoresist pattern as a mask, the thickness of the conductive transparent electrode film is selectively increased to 1000 mm.
2. The method of manufacturing a liquid crystal display panel according to claim 1, wherein the photoresist pattern is reduced to less than .ANG., and then the photoresist pattern is left to harden on the remaining conductive transparent electrode film.