JPH032833A - Production of liquid crystal display device - Google Patents

Abstract

PURPOSE:To form spacers which maintain the specified intersubstrate spacing by applying a photosensitive resin on the surface of the substrate having transparent electrodes coated with a metallic film having a light shielding effect and then exposing the photosensitive resin from the rear surface of the substrate. CONSTITUTION:The photosensitive resin 8 is applied on the surface of the substrate 1 coated with the metallic film 7 having the light shielding effect on the transparent electrodes 2 formed to a stripe shape and thereafter, the photosensitive resin 8 is exposed from the rear surface of the above-mentioned substrate 1. Namely, the metallic film applied on the transparent electrodes 2 has the light shielding effect to act as a photomask and, therefore, the need for mask registration is eliminated and the spacers 9 having a gap control effect are formed simply by executing the exposing from the rear surface of the substrate 1. The spacers are formed uniformly over the entire surface of picture elements in this way and the display grade is enhanced.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a method of manufacturing a liquid crystal display device having spacers between display electrodes to maintain a constant distance between substrates.

BACKGROUND OF THE INVENTION In recent years, progress has been made to increase the definition and capacity of liquid crystal display panels for application to new media equipment and OA equipment. With the trend toward higher definition and larger display capacity, it has become necessary to uniformly control the distance (gap) between substrates of a liquid crystal display device over a larger area with greater accuracy than ever before.

Conventionally, as a method of gap control for liquid crystal display devices,
A bead dispersion method in which spacer particles such as glass beads and resin beads are dispersed on a substrate, and a photolithography method in which a photosensitive resin is exposed and developed using a photomask to form spacers for gap control at predetermined positions. There is.

Problems to be Solved by the Invention In the spacer dispersion method, the spacer particles often aggregate due to the charging of the substrate, the charging of the spacer particles, and moisture absorption, and the dispersion on the substrate is not uniform. In the agglomerated areas, the gap locally becomes thicker when the substrates are bonded together, resulting in non-uniformity of the gap and failure of the alignment film of the liquid crystal, resulting in a reduction in display quality. be.

In the case of photolithography, it is necessary to align the photomask when exposing the photosensitive resin. High-definition display electrodes.

With the increase in capacity, it is necessary to perform mask alignment over a larger area with higher precision than ever before. Therefore, due to poor alignment of the mask, spacers are often not formed at predetermined positions, resulting in a decrease in yield.

Means for Solving the Problems In order to solve the above problems, what is the liquid crystal display device of the present invention and the method for manufacturing the liquid crystal display device? , tf#! ! A photosensitive resin is applied to the surface of the substrate, in which transparent electrodes formed in stripes are coated with a metal film having a light-shielding effect, and then the photosensitive resin is exposed to light from the back surface of the substrate.

Function According to the above structure, the metal wave film coated on the transparent electrode has a light shielding effect and acts as a photomask, so there is no need to perform mask alignment, and the gap control effect can be achieved by simply exposing from the back side of the substrate. It is possible to form a spacer with a

Examples Examples of the present invention will be described below with reference to the drawings.

FIG. 1 is an example of a cross-sectional view of a liquid crystal display device manufactured by the manufacturing method of the present invention. ■ is a glass substrate, 2 is a transparent electrode, 3
4 is a line spacer, 4 is an alignment film, 5 is a sealing material, and 6 is a liquid crystal layer. FIGS. 2(a) to 2(e) are process diagrams showing an example of the method for manufacturing the liquid crystal display device of the present invention.

To explain the steps according to the order of each figure, as shown in FIG. 2(a), electron beam (EB) evaporation is performed on the glass substrate 1
A thin film of indium tin oxide (ITO) is formed by sputtering. The surface resistance value of ITO is 10Ω/hole.

Thereafter, a photoresist is applied using a spinner or a roll coater, patterned by a predetermined method, and etched to form the transparent electrode 2.

Next, as shown in FIG. 2, a Nt-P metal film 7 is formed on the transparent electrode 2 by electroless Ni plating.

Electroless Ni plating is selective, and metal > JH97 is I
The thickness of the metal coating 7, which is deposited only on the transparent electrode 2 made of TO and not on the glass, is approximately 0.5 to 1.
It is about μm and has a sufficient light shielding effect.

As shown in FIG. 2(C), a negative photosensitive polyimide 8 is coated on the surface of the glass substrate 1 having the above structure using a spinner or a roll coater, and the zero-order glass substrate 1 is exposed to light from the back side. At this time, the metal coating 7 acts as a photomask, so the photosensitive polyimide on the metal coating 7 is not exposed, and only the space between the electrodes is exposed by zero-order development, which makes only the space part photosensitive. The polyimide remains, forming line spacers 9 for controlling the distance between the substrates (FIG. 2(d)).

The metal coating 7 is removed by etching. At this time, the line spacer 9 is not removed by etching (FIG. 2(e)).

After performing alignment treatment on the substrate on which line spacers are formed and the substrate on which no line spacers are formed by the method described above, the distance between the substrates is reduced by bonding the two substrates in orthogonal directions using a sealant. Can be held uniformly.

FIG. 3 shows the relationship between the spinner rotation speed and the distance between the substrates during coating of the photosensitive resin. Curve A indicates that the viscosity of the photosensitive resin is 50.
cpSB is 25 cp. By using the rotational speed of the spinner and the viscosity of the photosensitive resin as parameters, the distance between the substrates can be arbitrarily changed from about 1.5 to 6 μm.

Next, other embodiments will be described.

A conductive tape is attached to the transparent electrode groups formed in FIG. 2(a) to electrically connect all the transparent electrode groups. A glass substrate is immersed in a nickel sulfate solution, the transparent electrode group is used as a cathode, a Ni rod is used as an anode, and a pulse current waveform is generated between the two electrodes.
Alternatively, gold 1) iNi is deposited on the transparent electrode group by applying alternating alternating waveforms. The film thickness of metallic Ni is 1 to 3μ
It has a sufficient light-shielding effect.

Since the liquid crystal display device manufactured by the above manufacturing method can control the gap uniformly over the entire pixel, display unevenness is not observed and excellent display quality can be obtained. Since the construction method does not require a photomask and does not require mask alignment, it is easy to achieve higher definition electrode pitch or larger capacity.

Effects of the Invention In the method for manufacturing a liquid crystal display device of the present invention, the metal film coated on the transparent electrode for display acts as a photomask, so the spacer with a cap control function can be uniformly distributed over the entire pixel without the need for mask alignment. The display quality can be improved, the display can be made in high definition, and the display capacity can be increased, which is very effective.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view of a liquid crystal display device manufactured by the manufacturing method of the present invention, FIG. 2 is a process diagram showing the manufacturing method of the liquid crystal display device, and FIG. 3 is a diagram showing the relationship between the distance between substrates and the spinner rotation speed. This is a graph. l...Glass substrate, 2...Transparent electrode,
3...Line spacer, 4...Alignment film, 5...Sealing material, 6...Liquid crystal layer. Name of agent Patent attorney Shigetaka Awano 1 person Fig. 3 2-fi period' *gIL Tar-shi-no-mushi et al.

Claims (4)

[Claims] (1) After applying a photosensitive resin to the surface of a substrate having a plurality of transparent electrodes coated with a metal film having a light-shielding effect, the photosensitive resin is exposed to light from the back side of the substrate, thereby creating a space between the transparent electrodes. A method for manufacturing a liquid crystal display device, characterized by forming a spacer that maintains a constant distance. (2) The method for manufacturing a liquid crystal display device according to claim (1), wherein the metal film having a light-shielding effect is formed by electroless nickel plating. (3) The method for manufacturing a liquid crystal display device according to claim (1), wherein the metal film having a light-shielding effect is formed by electroplating. (4) The method for manufacturing a liquid crystal display device according to claim (1), wherein the photosensitive resin is of negative type.