Manufacturing method for liquid crystal display panels having high aperture ratio

• US 20040209389A1
• Filed: 01/08/2004
• Published: 10/21/2004
• Est. Priority Date: 04/17/2003
• Status: Abandoned Application

• Current Assignee: HannStar Display Corporation
• Original Assignee: HannStar Display Corporation
• Inventors: Liang, Gou Tsau
• Application Number:
  US10/752,502
• Publication Number:
  US 20040209389A1
• Time in Patent Office: Days
• US Class Current: 438/30
• CPC Class Codes: G02F 1/13458 Terminal pads
• CPC Class Codes: G02F 1/136227 Through-hole connection of the pixel electrode to the active element through an insulation layer
• CPC Class Codes: G02F 1/136236 using a grey or half tone lithographic process
• CPC Class Codes: H01L 27/1214 comprising a plurality of TFTs formed on a non-semiconducting substrate, e.g. driving circuits for AMLCDs
• CPC Class Codes: H01L 27/1288 employing particular masking sequences or specially adapted masks, e.g. half-tone mask
• CPC Class Codes: H01L 29/78669 with inverted-type structure, e.g. with bottom gate

Abstract

A protection layer is formed on a transparent substrate having a plurality of thin film transistors, and an exposure step is then carried out by means of a half-tone mask. An outer lead bonding area is located on the periphery of the transparent substrate. After the exposure and development steps, most of the protection layer in the outer lead bonding area is removed. With an etching step, the top of an insulation layer of the outer lead bonding area is exposed and a plurality of via holes are formed in the insulation layer, thus a metal layer is exposed from the via holes as outer lead bonding pads. Finally, a transparent conductive layer with desired patterns is formed on the protection layer, and the transparent conductive layer is extended into the via holes of the protection layer to connect with the thin film transistors.

Claims

1. A manufacturing method for liquid crystal display panels having a high aperture ratio, comprising the steps of:

providing a transparent substrate with thin film transistors forming therein, and the periphery of the transparent substrate having an outer lead bonding area formed by covering an insulation layer over metal wires;

forming a protection layer over the thin film transistors of the transparent substrate and outer lead bonding area;

applying a photo-etching process by a half-tone mask to the protection layer so as to remove a part of the protection layer at the outer lead bonding area for exposing the insulation layer on which outer lead bonding pads are predefinedly located; and

etching the remaining protection layer and the exposed insulation layer for exposing upper portions of the insulation layer and generating via holes through the insulation layer so as to expose the metal wires.

2. The manufacturing method for liquid crystal display panels having a high aperture ratio of claim 1, wherein the protection layer above the thin film transistors has at least one via hole formed by the etching process.

3. The manufacturing method for liquid crystal display panels having a high aperture ratio of claim 2, further comprising the step of:

forming a transparent conductive layer on the protection layer and inside the via holes so as to electrically contact the thin film transistors.

4. The manufacturing method for liquid crystal display panels having a high aperture ratio of claim 1, wherein the thin film transistor is a transistor having an etching structure.

5. The manufacturing method for liquid crystal display panels having a high aperture ratio of claim 1, wherein the thin film transistor is a transistor having a back-channel etching structure.

6. The manufacturing method for liquid crystal display panels having a high aperture ratio of claim 1, wherein the exposed portions of the metal wires are the outer lead bonding pads.

7. The manufacturing method for liquid crystal display panels having a high aperture ratio of claim 1, wherein the protection layer is made from a transparent organic material.

8. The manufacturing method for liquid crystal display panels having a high aperture ratio of claim 7, wherein the organic material is acrylate.

9. The manufacturing method for liquid crystal display panels having a high aperture ratio of claim 1, further comprising the step of:

sealing the liquid crystal display panel by pasting a sealant on the exposed portions of the insulation layer.

10. The manufacturing method for liquid crystal display panels having a high aperture ratio of claim 1, further comprising the step of:

interposing a silicon nitride layer between the insulation layer and the protection layer.

11. The manufacturing method for liquid crystal display panels having a high aperture ratio of claim 1, wherein the protection layer is a photoresist layer.