Color filter structure and method of making

• US 5,954,559 A
• Filed: 01/13/1997
• Issued: 09/21/1999
• Est. Priority Date: 01/13/1997
• Status: Expired due to Term

• Current Assignee: Hyundai Electronics America Incorporated (SK Hynix Inc.)
• Original Assignee: Image Quest Technologies, Inc.
• Inventors: Zhu, Shan, Holmberg, Scott H.
• Primary Examiner(s): Ramsey, Kenneth J.
• Application Number:
  US08/785,140
• Time in Patent Office: 981 Days
• Field of Search: 445/24, 430/7, 349/110
• US Class Current: 445/24
• CPC Class Codes: G02F 1/133357 Planarisation layers
• CPC Class Codes: G02F 1/133512 Light shielding layers, e.g. black matrix G02F1/136209 takes precedence

Abstract

An improved planar color filter structure to reduce defects in the display devices incorporating the color filter structures, including active matrix displays. A color filter substrate has a thicker polyamide black matrix formed thereon and a transparent polyamide layer formed over the black matrix. The transparent layer is exposed through the black matrix and developed to remove the unexposed portions over the black matrix. The resulting surface is substantially planar and facilitates the forming of the remaining layers to form a substantially planar color filter structure.

Claims

1. A method of manufacturing a color filter structure, wherein the improvement comprises the steps of:

forming a thick polyamide black matrix on a first substantially transparent substrate, forming a substantially transparent polyamide layer over said black matrix to a thickness substantially equal to the thickness of said black matrix, exposing said transparent layer through said substrate and developing said transparent layer to remove the layer portions over the black matrix forming a substantially planar surface.

2. The method as defined in claim 1 including forming a set of color filters over said planar surface.

3. The method as defined in claim 2 including forming a passivation layer over said color filters.

4. The method as defined in claim 3 including forming an ITO layer over said passivation layer.

5. The method as defined in claim 4 including forming a display device by adding spherical spacers onto said ITO layer and adding a liquid crystal material between said ITO layer and a second substrate.

6. The method as defined in claim 5 including forming an active matrix liquid crystal display device.

7. The method as defined in claim 1 including forming said transparent layer to a thickness slightly greater than the thickness of said black matrix.