Fabricating method of a pixel structure having electrical field shielding layer and storage capacitor with three transparent electrodes

• US 7,515,217 B2
• Filed: 10/04/2006
• Issued: 04/07/2009
• Est. Priority Date: 12/05/2003
• Status: Expired due to Term

• Current Assignee: AU Optronics Corporation
• Original Assignee: AU Optronics Corporation
• Inventors: Yang, Chien-Sheng
• Primary Examiner(s): SCHECHTER, ANDREW M
• Application Number:
  US11/309,825
• Publication Number:
  US 20070076156A1
• Time in Patent Office: 916 Days
• Field of Search: 349/38, 349/39
• US Class Current: 349/39
• CPC Class Codes: G02F 1/136213 Storage capacitors associated with the pixel electrode
• CPC Class Codes: G02F 1/136218 Shield electrodes
• CPC Class Codes: G02F 1/136227 Through-hole connection of the pixel electrode to the active element through an insulation layer

Abstract

A fabricating method of a pixel structure is disclosed. The pixel structure is disposed on a substrate. The pixel structure comprises a scan line, a data line, an active element, a capacitor electrode, a pixel electrode and an electric field shielding layer. The fabricating method of the pixel structure comprises forming the scan line, the data line and the active element on the substrate first. The scan line and the data line are electrically coupled to the active element. Then, the capacitor electrode and the electric field shielding layer are formed on the substrate. Finally, the pixel electrode is formed on the substrate, covering the capacitor electrode and electrically coupled to the active element. The pixel electrode and the capacitor electrode form a pixel storage capacitor. The electric field shielding layer can avoid the interference between the data line and the pixel electrode.

Claims

1. A method of fabricating a pixel structure, comprising:

forming an active element, a scan line and a data line on a substrate, the active element being electrically coupled to the scan line and the data line;

forming a capacitor electrode on the substrate;

simultaneously forming a transparent capacitor electrode over the capacitor electrode and forming an electrical field shielding layer above the data line; and

forming a pixel electrode over the transparent capacitor electrode, the pixel electrode electrically coupling to the active element, wherein the capacitor electrode, the transparent capacitor electrode and the pixel electrode form a pixel storage capacitor, and the electrical field shielding layer is between the data line and the pixel electrode, wherein the capacitor electrode, the electrical field shielding layer, and the pixel electrode are made from indium tin oxide or indium zinc oxide.

2. The method of fabricating a pixel structure of claim 1, wherein the active element comprises a low temperature polysilicon thin film transistor.

3. The method of fabricating a pixel structure of claim 2, while forming the data line, further comprising forming a source/drain conductive layer over the active element, wherein the active element is electrically coupled to the data line and the pixel electrode through the drain/source conductive layer.

4. The method of fabricating a pixel structure of claim 2, wherein the step of forming the active element comprises:

forming a polysilicon layer on the substrate;

forming a gate dielectric layer on the substrate, covering the polysilicon layer;

forming a gate terminal on the gate dielectric layer and over the polysilicon layer; and

forming a source/drain doped region within the polysilicon layer besides the gate terminal.

5. The method of fabricating a pixel structure of claim 4, wherein the step of forming the source/drain doped region comprises performing a doping process using the gate terminal as a hard mask for forming the source/drain doped region.

6. The method of fabricating a pixel structure of claim 2, after forming the data line, further comprising a step of forming a conductive layer over the active element, wherein the active element is electrically coupled to the data line through the conductive layer, and the pixel electrode is directly electrically coupled to the active element.

7. The method of fabricating a pixel structure of claim 1, wherein the step of forming the active element, the scan line and the data line on the substrate, the active element being electrically coupled to the scan line and the data line comprises sequentially forming the active element, the scan line and the data line on the substrate, the active element being electrically coupled to the scan line and the data line.

8. The method of fabricating a pixel structure of claim 1, wherein the capacitor electrode and the transparent capacitor electrode form a capacitor.

9. The method of fabricating a pixel structure of claim 1, wherein the transparent capacitor electrode and the pixel electrode form a capacitor.

10. The method of fabricating a pixel structure of claim 1, wherein the electrical field shielding layer shields the active element.