Liquid crystal display with pixels having an opening formed from a photosensitive resin with spacers attached

• US 6,078,378 A
• Filed: 11/24/1997
• Issued: 06/20/2000
• Est. Priority Date: 11/24/1997
• Status: Expired due to Term

• Current Assignee: Industrial Technology Research Institute
• Original Assignee: Industrial Technology Research Institute
• Inventors: Ting, Dai-Liang, Lu, Yong-Hong
• Primary Examiner(s): MALINOWSKI, WALTER J
• Application Number:
  US08/977,196
• Time in Patent Office: 939 Days
• Field of Search: 349/155, 349/156, 349/187
• US Class Current: 349/155
• CPC Class Codes: G02F 1/13394 spacers regularly patterned on the cell subtrate, e.g. walls, pillars G02F1/133377 takes precedence

Abstract

A method for controlling the cell gap of a liquid crystal display device is disclosed. A photo-sensitive polymer layer is coated over a substrate on which color filter, ITO and black matrix of the liquid crystal display device are formed. Spacers are uniformly sprayed and adhered on the photo-sensitive polymer. With a negative-type photo-polymer, a photo-mask can be used to expose the area of photo-sensitive polymer layer covering the the black matrix. The masked area is exposed, developed and removed by a conventional photo-lithographic process. The spacers attached to the masked area are also removed. The size of the spacers attached on the polymer above the thin-film transistors and the black matrix controls the cell gap.

Claims

1. A method for controlling a cell gap between two substrates of a liquid crystal display, comprising the steps of:

preparing a substrate for said liquid crystal display, said substrate comprising a plurality of pixels each having a pixel opening, black matrix and ITO manufactured thereon;

coating a photo-sensitive layer above said substrate for covering the pixel opening and black matrix of each pixel;

prebaking said photo-sensitive layer;

spraying and attaching a plurality of spacers uniformly on said photo-sensitive layer;

using a photo-mask for exposing a first portion of said photo-sensitive layer to a light source and masking a second portion of said photo-sensitive layer, said first portion covering the black matrix of each pixel, and said second portion covering the pixel opening of each pixel;

developing and removing the second portion of said photo-sensitive layer for exposing the pixel opening of each pixel; and

post-baking the first portion of said photo-sensitive layer.

2. The method for controlling a cell gap according to claim 1, further comprising a step of over-coating a protection layer on top of said spacers, said photo-sensitive layer and said substrate.

3. The method for controlling a cell gap according to claim 2, wherein said protection layer is further patterned by a photo-lithographic process including exposing and then developing said protection layer.

4. The method for controlling a cell gap according to claim 2, wherein the material of said protection layer is a negative-type photo-sensitive, positive-type photo-sensitive or thermo-curable material.

5. The method for controlling a cell gap according to claim 1, wherein said substrate is a TFT plate.