Method for manufacturing bottom substrate of liquid crystal display device

• US 20070020822A1
• Filed: 06/28/2006
• Published: 01/25/2007
• Est. Priority Date: 07/19/2005
• Status: Active Grant

• Current Assignee: AU Optronics Corporation
• Original Assignee: Quanta Display Incorporated (AUO Corp.)
• Inventors: Chou, Weng-Bing, Yang, Ko-Ching
• Granted Patent: US 7,335,538 B2
• Time in Patent Office: Days
• US Class Current: 438/149
• CPC Class Codes: G02F 1/1362 Active matrix addressed cells G02F1/134336, G02F1/134363 take precedence
• CPC Class Codes: G02F 1/136236 using a grey or half tone lithographic process

Abstract

A method for manufacturing liquid crystal display substrates comprises the steps of: (a) providing a substrate having a transparent electrode layer and a metal layer; (b) forming a patterned photoresist layer through half-tone or diffraction; (c) defining signal line area and thin film diode area, or pixel area and conductive electrode-lines by etching; and (d) forming an oxidized layer on partial surface of the metal layer. The disclosure here provides a patterning process of lithography and etching with one photolithography of one single mask in the manufacturing of liquid crystal display substrates. Furthermore, the method disclosed here can effectively increase the yield of manufacturing, and reduce the cost of manufacturing.

Claims

1. A method for manufacturing a bottom substrate of a liquid crystal display device, comprising following steps:

(a) providing a substrate having a transparent electrode layer and a metal layer;

wherein the transparent electrode layer is located between the substrate and the metal layer;

(b) forming a patterned photoresist on the metal layer, wherein the patterned photoresist has a first thickness and a second thickness;

(c) etching the patterned photoresist, the transparent electrode layer, and the metal layer over the substrate to define a signal line, a thin film diode area, a pixel area, and a conductive electrode-line;

wherein the thin film diode area has the transparent electrode layer, the metal layer, and a gap; and

(d) forming an oxidized layer on partial surface of the metal layer;

wherein the gap of the thin film diode is filled with the oxidized layer.

2. The method as claimed in claim 1, wherein the transparent electrode layer in step (a) is indium tin oxide or indium zinc oxide.

3. The method as claimed in claim 1, wherein the metal layer is tantalum layer.

4. The method as claimed in claim 1, wherein the patterned photoresist is formed through halftone or diffraction.

5. The method as claimed in claim 1, wherein the part of the photoresist of the first thickness is corresponding to the area for forming the signal lines, and that for forming thin film diode areas.

6. The method as claimed in claim 1, wherein the etching is dry etching.

7. The method as claimed in claim 1, wherein the etching is wet etching.

8. The method as claimed in claim 7, further comprising ashing the photoresist and the substrate having transparent layer and the metal layer by O₂ ashing after wet etching in step (c).

9. The method as claimed in claim 1, wherein the oxidized layer is formed through anode oxidation in step (d).

10. The method as claimed in claim 1, wherein the oxidized layer is Ta₂O₅ in step (d).