Buffer layer in flat panel display

• US 20030164350A1
• Filed: 09/21/2001
• Published: 09/04/2003
• Est. Priority Date: 09/01/1999
• Status: Active Grant

• Current Assignee: Mike E. Pugh, Robert J. Hanson, Won-Joo Kim
• Original Assignee: Mike E. Pugh, Robert J. Hanson, Won-Joo Kim
• Inventors: Hanson, Robert J., Kim, Won-Joo, Pugh, Mike E.
• Granted Patent: US 7,247,227 B2
• Time in Patent Office: Days
• US Class Current: 216/2
• CPC Class Codes: G02F 1/13439 characterised by their electrical, optical, physical properties; materials therefor; method of making
• CPC Class Codes: H01J 2329/08 Anode electrodes
• CPC Class Codes: H01J 2329/865 Connection of the spacing members to the substrates or electrodes
• CPC Class Codes: H01J 29/085 Anode plates, e.g. for screens of flat panel displays
• CPC Class Codes: H01J 31/127 using large area or array sources, i.e. essentially a source for each pixel group
• CPC Class Codes: H01J 9/20 Manufacture of screens on or from which an image or pattern is formed, picked up, converted or stored; Applying coatings to the vessel
• CPC Class Codes: H10K 50/81 Anodes
• CPC Class Codes: H10K 59/8051 Anodes
• CPC Class Codes: H10K 59/8723 Vertical spacers, e.g. arranged between the sealing arrangement and the OLED

Abstract

In devices such as flat panel displays, an aluminum oxide layer is provided between an aluminum layer and an ITO layer when such materials would otherwise be in contact to protect the ITO from optical and electrical defects sustained, for instance, during anodic bonding and other fabrication steps. This aluminum oxide barrier layer is preferably formed either by: (1) partially or completely anodizing an aluminum layer formed over the ITO layer, or (2) an in situ process forming aluminum oxide either over the ITO layer or over an aluminum layer formed on the ITO layer. After either of these processes, an aluminum layer is then formed over the aluminum oxide layer.

Claims

1. A method of manufacturing a tin oxide/aluminum structure, comprising:

forming a tin oxide layer;

forming an aluminum oxide layer over the tin oxide layer; and

forming a top aluminum layer over the aluminum oxide layer.

2. The method of claim 1, wherein the tin oxide layer is indium tin oxide.

3. The method of claim 1, wherein the aluminum oxide layer is formed by anodizing aluminum.

4. The method of claim 3, wherein the aluminum is anodized by a process selected from the group consisting of using electrolytic anodization, a wet oxidizing agent and an oxygen plasma.

5. The method of claim 3, wherein the aluminum is partially anodized to form a sandwiched aluminum layer between the tin oxide layer and the aluminum oxide layer formed by anodization.

6. The method of claim 3, wherein the aluminum is completely anodized.

7. The method of claim 1, further comprising depositing an intermediate aluminum layer over the tin oxide layer prior to forming the aluminum oxide layer.

8. The method of claim 7, wherein the intermediate aluminum layer is formed by sputtering.

9. The method of claim 1, wherein the aluminum oxide layer is formed by reactive sputtering.

10. The method of claim 1, wherein the top aluminum layer is formed by sputtering.

11. The method of claim 1, wherein the aluminum oxide layer comprises AlO_x where x is between about 0.25 and 1.5.

12. A tin oxide/aluminum structure, comprising:

a tin oxide layer over a substrate;

an aluminum oxide layer over the tin oxide layer; and

an aluminum layer over the aluminum oxide layer.

13. The structure of claim 12, wherein the tin oxide layer comprises indium tin oxide.

14. The structure of claim 12, further comprising a second aluminum layer between the tin oxide layer and the aluminum oxide layer.

15. The structure of claim 14, wherein the second aluminum layer has a thickness of between about 1000 and 5000 Å

.

16. The structure of claim 12, wherein the aluminum oxide layer has a thickness of between about 100 and 10,000 Å

.

17. The structure of claim 16, wherein the aluminum oxide layer has a thickness of between about 300 and 5,000 Å

.

18. The structure of claim 17, wherein the aluminum oxide layer has a thickness of between about 500 and 1,500 Å

.

19. The structure of claim 12, wherein the aluminum layer over the aluminum oxide layer has a thickness of between about 4,500 and 6,000 Å

.

20. The structure of claim 12, wherein the aluminum oxide layer comprises AlO_x where x is between about 0.25 and 1.5.

21. A method of protecting an indium tin oxide layer in the presence of aluminum, comprising forming an aluminum oxide layer between the indium tin oxide layer and the aluminum.

22. The method of claim 21, wherein the aluminum oxide layer is formed by anodizing aluminum.

23. The method of claim 21, wherein the aluminum oxide layer is formed by reactive sputtering.

24. A method of fabricating a display device structure, comprising:

forming an indium tin oxide layer;

forming an aluminum oxide layer over the tin oxide layer;

forming an aluminum layer over the aluminum oxide layer;

exposing the structure to an indium tin oxide-corrosive medium, the aluminum oxide preventing diffusion of the corrosive medium through the aluminum layer to the indium tin oxide layer; and

removing the aluminum oxide and aluminum layers once the structure is no longer exposed to the indium tin oxide-corrosive medium.

25. The method of claim 24, wherein the aluminum oxide and aluminum layers are removed by etching.

26. The method of claim 25, wherein the layers are removed using an etchant comprising phosphoric acid.

27. The method of claim 25, wherein the aluminum oxide and aluminum layers are etched at a temperature up to about 60°

C.

28. A display device structure, comprising:

a substrate;

an electrically conductive and optically transparent layer over the substrate;

an aluminum oxide layer over the electrically conductive and optically transparent layer; and

an aluminum layer over the aluminum oxide layer.

29. The structure of claim 28, wherein the electrically conductive and optically transparent layer comprises indium tin oxide.

30. The structure of claim 28, further comprising a second aluminum layer between the electrically conductive and optically transparent layer and the aluminum oxide layer.

31. The structure of claim 28, wherein the aluminum oxide layer has a thickness of between about 500 and 1,500 Å

.

32. The structure of claim 28, wherein the aluminum layer over the aluminum oxide layer has a thickness of between about 4,500 and 6,000 Å

.

33. The structure of claim 28, wherein the aluminum oxide layer comprises AlO_x where x is between about 0.25 and 1.5.

34. A method for protecting the optical and electrical properties of an ITO layer for a flat panel display device during a spacer fabrication process using an aluminum bonding layer, comprising forming an aluminum oxide layer between the ITO layer and the aluminum bonding layer.

35. The method of claim 34, wherein the aluminum bonding layer is used to bond spacers thereto.