Organic light emitting diode (OLED) display panel and method of forming polysilicon channel layer thereof

• US 20070126000A1
• Filed: 04/03/2006
• Published: 06/07/2007
• Est. Priority Date: 12/01/2005
• Status: Abandoned Application

• Current Assignee: AU Optronics Corporation
• Original Assignee: AU Optronics Corporation
• Inventors: Chen, Ming-Yan, Lin, Jiunn-Yi
• Application Number:
  US11/395,338
• Publication Number:
  US 20070126000A1
• Time in Patent Office: Days
• US Class Current: 257/40
• CPC Class Codes: H01L 27/1285 using control of the annealing or irradiation parameters, e.g. using different scanning direction or intensity for different transistors
• CPC Class Codes: H01L 27/1296 adapted to increase the uniformity of device parameters
• CPC Class Codes: H10K 59/12 Active-matrix OLED [AMOLED] displays

Abstract

An organic light emitting diode (OLED) display panel and a method of forming a polysilicon channel layer thereof are provided. In the method, firstly, a substrate having a polysilicon layer disposed thereon is provided. Then, a dopant atom not selected from the IIIA group and the VA group is doped inside the polysilcon layer to form a polysilicon channel layer.

Claims

1. An organic light emitting diode (OLED) display panel, comprising:

a substrate;

a pixel disposed on the substrate; and

a first thin film transistor disposed inside the pixel and comprising a first polysilicon channel layer, wherein a first dopant atom not selected from the III A group and the VA group is doped inside the first polysilicon channel layer.

2. The panel according to claim 1, wherein the doping concentration of the first dopant atom in the first polysilicon channel layer ranges 10¹¹˜

10¹⁵ atoms/cm².

3. The panel according to claim 1, wherein the first thin film transistor further comprises a first gate, a first source and a first drain, the first source and the first drain are correspondingly and electrically connected to two ends of the first polysilicon channel layer, the first source is electrically connected to a first constant voltage, and the OLED display panel further comprises:

a first scan line and a second scan line both disposed on the substrate in parallel;

a first data line and a second data line both disposed on the substrate in parallel, perpendicular to and alternating with the first scan line and the second scan line to define the pixel;

a second thin film transistor disposed inside the pixel and comprising a second gate, a second source, a second drain and a second polysilicon channel layer, wherein the second source and the second drain are correspondingly and electrically connected to two ends of the second polysilicon channel layer, the second gate is electrically connected to the first scan line, the second source is electrically connected to the first data line, and the second drain is electrically connected to the first gate;

a storage capacitor disposed inside the pixel, wherein one end of the storage capacitor is electrically connected between the second drain and the first gate, the other end of the storage capacitor is electrically connected between the first source and the first constant voltage; and

an organic electroluminescent device (OELD) disposed inside the pixel to be electrically connected to the first drain and a second constant voltage.

4. The panel according to claim 3, wherein a second dopant atom not selected from the IIIA group and the VA group is doped inside the second polysilicon channel layer.

5. The panel according to claim 4, wherein the first dopant atom and the second dopant atom are neutral atoms.

6. The panel according to claim 5, wherein the first dopant atom and the second dopant atom comprise inert gas and/or the IVA group.

7. The panel according to claim 6, wherein the first dopant atom and the second dopant atom respectively are selected from the group consisting of helium (He), neon (Ne), argon (Ar), krypton (Kr), xenon (Xe) and radon (Rn) and any combination thereof.

8. The panel according to claim 4, wherein the doping concentration of the first dopant atom in the first polysilicon channel layer is larger than the doping concentration of the second dopant atom in the second polysilicon channel layer.

9. A method of forming a polysilicon channel layer, comprising:

providing a substrate having a first polysilicon layer and a second polysilicon layer disposed thereon;

covering the substrate by a first mask, wherein the substrate has a first opening for exposing the first polysilicon layer; and

doping a first dopant atom not selected from the IIIA group and the VA group inside the first polysilicon layer to form a first polysilicon channel layer.

10. The method according to claim 9, wherein the doping concentration of the first dopant atom in the first polysilicon channel layer ranges 10¹¹˜

10¹⁵ atoms/cm².

11. The method according to claim 9, further comprising:

removing the first mask and covering the substrate by a second mask, wherein the second mask has a second opening for exposing the second polysilicon layer; and

doping a second dopant atom not selected from the IIIA group and the VA group inside the second polysilicon layer to form a second polysilicon channel layer, wherein the doping concentration of the second dopant atom in the second polysilicon channel layer is the same or different with the doping concentration of the first dopant atom in the first polysilicon channel layer.

12. The method according to claim 11, wherein the first dopant atom and the second dopant atom are neutral atoms.

13. The method according to claim 12, wherein the first dopant atom and the second dopant atom comprise inert gas and/or the IVA group.

14. The method according to claim 13, wherein the first dopant atom and the second dopant atom respectively are selected from the group consisting of helium (He), neon (Ne), argon (Ar), krypton (Kr), xenon (Xe) and radon (Rn) and any combination thereof.

15. The method according to claim 14, wherein the doping concentration of the first dopant atom in the first polysilicon channel layer is larger than the doping concentration of the second dopant atom in the second polysilicon channel layer.

16. A method of forming a polysilicon channel layer, comprising:

providing a substrate having a first polysilicon layer and a second polysilicon layer disposed thereon;

covering the substrate by a first mask, wherein the first mask has a first opening and a second opening for respectively exposing the first polysilicon layer and the second polysilicon layer;

doping a first dopant atom not selected from the IIIA group and the VA group inside the first polysilicon layer and the second polysilicon layer to respectively form a first polysilicon channel layer and a second polysilicon channel layer, wherein the doping concentration of the first dopant atom in the first polysilicon channel layer is the same with the doping concentration of the first dopant atom in the second polysilicon channel layer;

removing the first mask and covering the substrate by a second mask, wherein the second mask has a third opening for exposing the first polysilicon channel layer; and

doping a second dopant atom inside the first polysilicon channel layer to form a third polysilicon channel layer, wherein the total doping concentration of the first dopant atom and the second dopant atom in the third polysilicon channel layer is larger than the doping concentration of the first dopant atom in the second polysilicon channel layer.

17. The method according to claim 16, wherein the first dopant atom and the second dopant atom are neutral atoms.

18. The method according to claim 17, wherein the first dopant atom and the second dopant atom comprise inert gas and/or the IV A group.

19. The method according to claim 18, wherein the first dopant atom and the second dopant atom respectively are selected from the group consisting of helium (He), neon (Ne), argon (Ar), krypton (Kr), xenon (Xe) and radon (Rn) and any combination thereof.

20. The method according to claim 16, wherein the total doping concentration of the first dopant atom and the second dopant atom in the third polysilicon channel layer ranges 10¹¹˜

10¹⁵ atoms/cm².