OLED MICRO-CAVITY STRUCTURE AND METHOD OF MAKING

• US 20140191202A1
• Filed: 04/10/2013
• Published: 07/10/2014
• Est. Priority Date: 01/04/2013
• Status: Active Grant

• Current Assignee: LG Display Co., Ltd.
• Original Assignee: LG Display Co., Ltd.
• Inventors: SHIM, Sungbin, KIM, Se June
• Granted Patent: US 9,583,734 B2
• Time in Patent Office: Days
• US Class Current: 257/40
• CPC Class Codes: H10K 50/813 characterised by their shape
• CPC Class Codes: H10K 50/816 Multilayers, e.g. transparent multilayers
• CPC Class Codes: H10K 50/818 Reflective anodes, e.g. ITO combined with thick metallic layers
• CPC Class Codes: H10K 50/852 comprising a resonant cavity structure, e.g. Bragg reflector pair
• CPC Class Codes: H10K 59/1201 Manufacture or treatment
• CPC Class Codes: H10K 59/30 Devices specially adapted for multicolour light emission
• CPC Class Codes: H10K 59/35 comprising red-green-blue [RGB] subpixels
• CPC Class Codes: H10K 59/351 comprising more than three subpixels, e.g. red-green-blue-white [RGBW]
• CPC Class Codes: H10K 59/38 comprising colour filters or colour changing media [CCM]
• CPC Class Codes: H10K 71/00 Manufacture or treatment specially adapted for the organic devices covered by this subclass
• CPC Class Codes: Y02E 10/549 Organic PV cells
• CPC Class Codes: Y02P 70/50 Manufacturing or production processes characterised by the final manufactured product

Abstract

An organic light emitting diode, including: a substrate; a first cavity electrode in a first micro-cavity region of the substrate; a first transparent electrode of a first thickness in the first micro-cavity region, the first transparent electrode overlaps beyond a first side of the first cavity electrode; a first emissive layer in electrical connection with the first transparent electrode; and a cathode layer on the first emissive layer.

Claims

1. An organic light emitting diode, comprising:

a substrate;

a first cavity electrode in a first micro-cavity region of the substrate;

a first transparent electrode of a first thickness in the first micro-cavity region, the first transparent electrode overlaps beyond a first side of the first cavity electrode;

a first emissive layer in electrical connection with the first transparent electrode; and

a cathode layer on the first emissive layer.

2. The organic light emitting diode according to claim 1, wherein the first transparent electrode overlaps beyond a second side of the first cavity electrode that is opposite to the first side.

3. The organic light emitting diode of claim 1, wherein the cathode layer is reflective.

4. The organic light emitting diode of claim 1, wherein the cathode layer is semi-transmissive.

5. The organic light emitting diode of claim 1, wherein the first cavity electrode is reflective.

6. The organic light emitting diode of claim 1, wherein the first cavity electrode is semi-transmissive.

7. The organic light emitting diode according to claim 1, further comprising:

a second cavity electrode in a second micro-cavity region of the substrate;

a third cavity electrode in a third micro-cavity region of the substrate;

a second transparent electrode of a second thickness in the second micro-cavity region, the second transparent layer overlaps beyond a third side of the second cavity electrode;

a third transparent electrode of a third thickness in the third micro-cavity region, the third transparent layer overlaps beyond a fourth side of the third cavity electrode;

a second emissive layer in electrical connection with the second transparent electrode of the second micro-cavity region; and

a third emissive layer in electrical connection with a third transparent electrode of the third micro-cavity region, wherein the cathode layer is on the second and third emissive layers.

8. The organic light emitting diode of claim 7, wherein the cathode layer comprises a first cathode layer in the first micro-cavity region, a second cathode layer in the second micro-cavity region, a third cathode layer in the third micro-cavity region.

9. The organic light emitting diode of claim 7, wherein the second thickness is less than the first thickness.

10. The organic light emitting diode of claim 9, wherein the third thickness is less than the second thickness.

11. The organic light emitting diode of claim 9, wherein the second and third cavity electrodes are reflective.

12. The organic light emitting diode of claim 9, wherein the second and third cavity electrodes are semi-transmissive

13. The organic light emitting diode of claim 7, wherein the first, second and third emissive layers emit a same color.

14. An organic light emitting diode on a substrate, comprising:

a first cavity electrode having a first width in a first sub-pixel region of the substrate;

a first transparent electrode having a second width and positioned on the first cavity electrode, wherein the second width is larger than the first width;

a first emissive layer in electrical connection with the first transparent electrode; and

a cathode layer on the first emissive layer.

15. The organic light emitting diode according to claim 14, wherein the first transparent electrode overlaps beyond both a first side of the first cavity electrode and a second side of the first cavity electrode opposite to the first side.

16. The organic light emitting diode of claim 15, wherein the first cavity electrode is reflective.

17. The organic light emitting diode of claim 15, wherein the first cavity electrode is semi-transmissive.

18. The organic light emitting diode of claim 15, wherein the cathode layer electrode is reflective.

19. The organic light emitting diode of claim 15, wherein the cathode layer electrode is semi-transmissive.

20. An organic light emitting diode, comprising:

a substrate;

an first sub-pixel region, a second sub-pixel region, and a third sub-pixel region on the substrate;

a first cavity electrode in the first sub-pixel region of the substrate;

a second cavity electrode in the second sub-pixel region of the substrate;

a third cavity electrode in the third sub-pixel region of the substrate;

a first transparent electrode of a first thickness in the first sub-pixel region, the first transparent electrode overlaps beyond a side of the first cavity electrode;

second transparent electrodes of a second thickness in the first sub-pixel and second sub-pixel regions, the second transparent electrode in the second sub-pixel region overlaps beyond a side of the second cavity electrode;

third transparent electrodes of a third thickness in the first sub-pixel, second sub-pixel, third sub-pixel regions, the third transparent electrode in the third sub-pixel region overlaps beyond a side of the third cavity electrode;

an emissive layer being in electrical connection with the first, second and third transparent electrodes; and

a cathode layer on the emissive layer.

21. The organic light emitting diode of claim 20, wherein the first sub-pixel region is Red sub-pixel region, the second sub-pixel region is Green sub-pixel region, and the third sub-pixel region is Blue sub-pixel region.

22. The organic light emitting diode of claim 20, wherein the first, second, and third cavity electrodes are reflective.

23. The organic light emitting diode of claim 20, wherein the first, second, and third cavity electrodes are semi-transmissive.

24. The organic light emitting diode of claim 20, wherein the cathode layer on the emissive layer is reflective.

25. The organic light emitting diode of claim 24, wherein the cathode layer on the emissive layer is semi-transmissive.

26. The organic light emitting diode of claim 20, further comprising:

a fourth sub-pixel region on the substrate;

a fourth cavity electrode in the fourth sub-pixel region of the substrate; and

a fourth transparent electrode of a fourth thickness in the fourth sub-pixel region, the fourth transparent electrode overlaps beyond a side of the fourth cavity electrode, wherein the emissive layer is in electrical connection with the fourth transparent electrode.

27. The organic light emitting diode of claim 26, the fourth sub-pixel region is white sub-pixel region.

28. The organic light emitting diode of claim 26, the fourth thickness is same as one of the first thickness, the second thickness and the third thickness

29. A method of making an organic light emitting diode on a substrate, comprising:

forming a cavity electrode layer across first, second and third micro-cavity regions of the substrate;

forming a first transparent layer of a first thickness in the first micro-cavity region;

forming second transparent layers of a second thickness in the first and second micro-cavity regions;

forming third transparent layers of a third thickness in the first, second and third micro-cavity regions;

etching the cavity electrode layer such that the first transparent layer in the first micro-cavity region overlaps beyond a first side of a first cavity electrode, the second transparent layer in the second micro-cavity region overlaps beyond a second side of a second cavity electrode, and the third transparent layer in the third micro-cavity region overlaps beyond a third side of a third cavity electrode;

forming a first bank between the first and second micro-cavity regions and a second bank between the second and third micro-cavity regions;

forming a first emissive layer in electrical connection with the third transparent layer of the first micro-cavity region;

forming a second emissive layer in electrical connection with the third transparent layer of the second micro-cavity region;

forming a third emissive layer in electrical connection with the third transparent layer of the third micro-cavity region; and

forming a cathode layer on the first, second and third emissive layers.

30. The method of claim 29, wherein the first, second and third emissive layers are formed at the same time for a same color.

31. A method of making an organic light emitting diode on a substrate, comprising:

forming a cavity electrode layer across first, second and third micro-cavity regions of the substrate;

forming first transparent layers of a first thickness in the first, second and third micro-cavity region;

forming second transparent layers of a second thickness in the first and second micro-cavity regions;

forming a third transparent layer of a third thickness in the first micro-cavity regions;

etching the cavity electrode layer such that the first transparent layer in the first micro-cavity region overlaps beyond a first side of a first cavity electrode, the first transparent layer in the second micro-cavity region overlaps beyond a second side of a second cavity electrode, and the first transparent layer in the third micro-cavity region overlaps beyond a third side of a third cavity electrode;

forming a first bank between the first and second micro-cavity regions and a second bank between the second and third micro-cavity regions;

forming a first emissive layer in electrical connection with the third transparent layer of the first micro-cavity region;

forming a second emissive layer in electrical connection with the second transparent layer of the second micro-cavity region;

forming a third emissive layer in electrical connection with the first transparent layer of the third micro-cavity region; and

forming a cathode layer on the first, second and third emissive layers.

32. The method of claim 31, wherein the first, second and third emissive layers are formed at the same time for a same color.