Dual panel type organic electroluminescent display device and method of fabricating the same

• US 6,870,197 B2
• Filed: 06/30/2003
• Issued: 03/22/2005
• Est. Priority Date: 08/14/2002
• Status: Expired due to Term

• Current Assignee: LG Display Co., Ltd.
• Original Assignee: LG Philips LCD Company Limited (LG Display Co., Ltd.)
• Inventors: Yoo, Choong-Keun, Park, Jae-Yong, Lee, Nam-Yang, Kim, Ock-Hee, Kim, Kwan-Soo
• Primary Examiner(s): Brock, II, Paul E
• Application Number:
  US10/608,471
• Publication Number:
  US 20040031959A1
• Time in Patent Office: 631 Days
• Field of Search: 257/628, 257/98, 257/E31.095, 257/E31.129, 257/E33.061, 438/115, 438 29- 32, 438 69- 72, 313499-501
• US Class Current: 257/98
• CPC Class Codes: H10K 2102/3026 Top emission
• CPC Class Codes: H10K 50/846 comprising getter material or desiccants
• CPC Class Codes: H10K 59/127 comprising two substrates, e.g. display comprising OLED array and TFT driving circuitry on different substrates
• CPC Class Codes: H10K 59/35 comprising red-green-blue [RGB] subpixels
• CPC Class Codes: H10K 59/874 including getter material or desiccant

Abstract

A dual panel type organic electroluminescent device includes first and second substrates bonded together by a seal pattern, the first and second substrates including a plurality of sub-pixel regions, a plurality of array elements including a plurality of thin film transistors on the first substrate, a plurality of organic electroluminescent diodes on the second substrate, each of the organic electroluminescent diodes having a first electrode on a rear surface of the second substrate, an organic electroluminescent layer on a rear surface of the first electrode, a second electrode on a rear surface of the organic electroluminescent layer that corresponds to respective ones of the sub-pixel regions, a plurality of connecting electrodes connected to the thin film transistors over the first substrate, a plurality of electrical connecting patterns formed on each of the connecting electrodes, each of the electrical connecting patterns electrically interconnecting each of the thin film transistors to one of the organic electroluminescent diodes, and a plurality of hygroscopic patterns formed on portions of the connecting electrodes.

Claims

1. A dual panel type organic electroluminescent display device, comprising:

first and second substrates bonded together by a seal pattern, the first and second substrates including a plurality of sub-pixel regions;

a plurality of array elements including a plurality of thin film transistors on the first substrate;

a plurality of organic electroluminescent diodes on the second substrate, each of the organic electroluminescent diodes having a first electrode on a rear surface of the second substrate, an organic electroluminescent layer on a rear surface of the first electrode, a second electrode on a rear surface of the organic electroluminescent layer that corresponds to respective ones of the sub-pixel regions;

a plurality of connecting electrodes connected to the thin film transistors over the first substrate;

a plurality of electrical connecting patterns formed on each of the connecting electrodes, each of the electrical connecting patterns electrically interconnecting each of the thin film transistors to one of the organic electroluminescent diodes; and

a plurality of hygroscopic patterns formed on portions of the connecting electrodes.

2. The device according to claim 1, wherein the hygroscopic patterns are disposed over an entire surface of the first substrate except for portions corresponding to the electrical connecting patterns.

3. The device according to claim 1, wherein the hygroscopic patterns are disposed corresponding to the connecting electrodes within the sub-pixel regions.

4. The device according to claim 3, wherein each of the hygroscopic patterns are disposed to surround each of the electrical connecting patterns.

5. The device according to claim 3, wherein the hygroscopic patterns are disposed on a lower portion of each of the connecting electrodes and the electrical connecting patterns are disposed on an upper portion of each of the connecting electrodes.

6. The device according to claim 3, wherein the hygroscopic patterns are disposed along a side portion of each of the connecting electrodes and the electrical connecting patterns are disposed along another side portion of each of the connecting electrodes.

7. The device according to claim 1, wherein the connecting electrodes include drain electrodes of the thin film transistors.

8. The device according to claim 1, wherein the hygroscopic patterns are formed over the first substrate using a shadow mask process.

9. The device according to claim 1, wherein the hygroscopic patterns are formed of a dispensed gel-type hygroscopic material over the first substrate.

10. The device according to claim 1, wherein each of the electrical connecting patterns have a pillar shape.

11. The device according to claim 1, wherein the thin film transistors include switching thin film transistors and driving thin film transistors.

12. The device according to claim 11, wherein the thin film transistors connected to the organic electroluminescent diodes by the electrical connecting patterns are the driving thin film transistors.

13. The device according to claim 12, wherein each of the driving thin film transistors include a gate electrode, a semiconductor layer, a drain electrode, and a source electrode.

14. The device according to claim 13, wherein one of the drain and source electrodes is one of the connecting electrodes electrically connected to the second electrodes of the organic electroluminescent diodes through the electrical connecting patterns.

15. The device according to claim 1, wherein the hygroscopic patterns are formed after forming the electrical connecting patterns on the connecting electrodes.

16. A method of fabricating a dual panel type organic electroluminescent display device, comprising:

forming a plurality of array elements including a plurality of thin film transistors on a first substrate;

forming a plurality of organic electroluminescent diodes on a second substrate, each of the organic electroluminescent diodes having a first electrode on a rear surface of the second substrate, an organic electroluminescent layer on a rear surface of the first electrode, a second electrode on a rear surface of the organic electroluminescent layer that corresponds to one of a plurality sub-pixel regions;

forming a plurality of connecting electrodes connected to the thin film transistors over the first substrate;

forming a plurality of electrical connecting patterns on each of the connecting electrodes, each of the electrical connecting patterns electrically interconnecting each of the thin film transistors to one of the organic electroluminescent diodes;

forming a plurality of hygroscopic patterns on portions of the connecting electrodes; and

bonding the first and second substrates bonded together with a seal pattern.

17. The method according to claim 16, wherein the hygroscopic patterns are disposed over an entire surface of the first substrate except for portions corresponding to the electrical connecting patterns.

18. The method according to claim 16, wherein the hygroscopic patterns are disposed corresponding to the connecting electrodes within the sub-pixel regions.

19. The method according to claim 18, wherein each of the hygroscopic patterns are disposed to surround each of the electrical connecting patterns.

20. The method according to claim 18, wherein the hygroscopic patterns are disposed on a lower portion of each of the connecting electrodes and the electrical connecting patterns are disposed on an upper portion of each of the connecting electrodes.

21. The method according to claim 18, wherein the hygroscopic patterns are disposed along a side portion of each of the connecting electrodes and the electrical connecting patterns are disposed along another side portion of each of the connecting electrodes.

22. The method according to claim 16, wherein the connecting electrodes include drain electrodes of the thin film transistors.

23. The method according to claim 16, wherein the hygroscopic patterns are formed over the first substrate using a shadow mask process.

24. The method according to claim 16, wherein the hygroscopic patterns are formed of a dispensed gel-type hygroscopic material over the first substrate.

25. The method according to claim 16, wherein each of the electrical connecting patterns have a pillar shape.

26. The method according to claim 16, wherein the thin film transistors include switching thin film transistors and driving thin film transistors.

27. The method according to claim 26, wherein the thin film transistors connected to the organic electroluminescent diodes by the electrical connecting patterns are the driving thin film transistors.

28. The method according to claim 27, wherein each of the driving thin film transistors include a gate electrode, a semiconductor layer, a drain electrode, and a source electrode.

29. The method according to claim 28, wherein one of the drain and source electrodes is one of the connecting electrodes electrically connected to the second electrodes of the organic electroluminescent diodes through the electrical connecting patterns.

30. The method according to claim 16, wherein the hygroscopic patterns are formed after forming the electrical connecting patterns on the connecting electrodes.