Organic light emitting diode

• US 20050088080A1
• Filed: 07/30/2004
• Published: 04/28/2005
• Est. Priority Date: 10/22/2003
• Status: Active Grant

• Current Assignee: National Taiwan University (Government of The Republic of China), HannStar Display Corporation
• Original Assignee: National Taiwan University (Government of The Republic of China), HannStar Display Corporation
• Inventors: Chen, Chieh-Wei, Cheng, Jia-Shyong, Wu, Chung-Chih, Chiang, Huo-Hsien, Hsieh, Ping-Yuan
• Granted Patent: US 7,321,196 B2
• Time in Patent Office: Days
• US Class Current: 313/504
• CPC Class Codes: H10K 2102/3026 Top emission
• CPC Class Codes: H10K 50/17 Carrier injection layers
• CPC Class Codes: H10K 50/171 Electron injection layers
• CPC Class Codes: H10K 50/818 Reflective anodes, e.g. ITO combined with thick metallic layers
• CPC Class Codes: H10K 50/82 Cathodes
• CPC Class Codes: H10K 85/324 comprising aluminium, e.g. Alq3
• CPC Class Codes: H10K 85/631 Amine compounds having at least two aryl rest on at least one amine-nitrogen atom, e.g. triphenylamine

Abstract

An organic light emitting diode is provided. The organic light emitting diode includes a substrate, an electrode structure formed on said substrate, an organic layer formed on said electrode structure and a transparent electrode structure having at least one transparent dielectric layer with a relatively higher refraction index and deposited on said organic layer by thermal evaporation.

Claims

1. An organic light emitting diode, comprising:

a substrate;

an electrode structure formed on said substrate;

an organic layer formed on said electrode structure; and

a transparent electrode structure having at least one transparent dielectric layer with a rather high refraction index and deposited on said organic layer by thermal evaporation.

2. The organic light emitting diode according to claim 1 wherein said electrode structure is an anode.

3. The organic light emitting diode according to claim 1 wherein said transparent electrode structure comprises a thin metal layer.

4. The organic light emitting diode according to claim 3 wherein said thin metal layer is one selected from a group consisting of layers of Al, Ag, Cr, and Mo, stack layers thereof and a layer of a mixture thereof.

5. The organic light emitting diode according to claim 3 wherein said thin metal layer has a thickness less than 40 nm.

6. The organic light emitting diode according to claim 1 wherein said transparent electrode structure comprises an electron injection layer.

7. The organic light emitting diode according to claim 6 wherein said electron injection layer comprises an Al layer.

8. The organic light emitting diode according to claim 7 wherein said Al layer has a thickness less than 4 nm.

9. The organic light emitting diode according to claim 7 wherein said electron injection layer further comprises an alkali-salt layer.

10. The organic light emitting diode according to claim 9 wherein said alkali-salt layer has a thickness less than 0.1 and 4 nm.

11. The organic light emitting diode according to claim 9 wherein said alkali-salt layer is deposited on said organic layer.

12. The organic light emitting diode according to claim 9 wherein said alkali-salt layer is one selected from a group consisting of layers of LiF, LiO2, and NaCl, stack layers thereof and a layer of a mixture thereof.

13. The organic light emitting diode according to claim 1 wherein said rather high refraction index is greater than 2.0 within the wavelength of the visible light.

14. The organic light emitting diode according to claim 1 wherein said transparent dielectric layer with said relatively higher refraction index comprises a TeOx layer.

15. The organic light emitting diode according to claim 1 wherein said electrode structure comprises an conductive layer.

16. The organic light emitting diode according to claim 15 wherein said conductive layer comprises a metal oxide layer.

17. The organic light emitting diode according to claim 16 wherein said conductive layer further comprises an conductive polymer layer formed on the metal oxide layer.

18. The organic light emitting diode according to claim 16 wherein said metal oxide layer is one selected from a group consisting of layers of indium tin oxide (ITO), indium zinc oxide (IZO), indium oxide, tin oxide, zinc oxide, aluminum zinc oxide (AZO), and tellurium oxide, stack layers thereof and a layer of a mixture thereof.

19. The organic light emitting diode according to claim 17 wherein said conductive polymer layer is one selected from a group consisting of layers of polyethylene dioxythiophene/polystyrene sulphonate (PEDOT/PSS), 4, 4′

, 4″

-tris(3-methylphenylphenylamino)triphenylamine (m-MTDATA), and polyaniline (PANI), stack layers thereof and a layer of a mixture thereof.

20. The organic light emitting diode according to claim 15 wherein said conductive layer comprises a metal layer.

21. The organic light emitting diode according to claim 20 wherein said conductive layer further comprises a metal oxide layer formed on said metal layer.

22. The organic light emitting diode according to claim 21 wherein said metal oxide layer is one selected from a group consisting of layers of indium tin oxide (ITO), indium zinc oxide (IZO), indium oxide, tin oxide, zinc oxide, aluminum zinc oxide (AZO), and tellurium oxide, stack layers thereof and a layer of a mixture thereof.

23. The organic light emitting diode according to claim 21 wherein said metal oxide layer is formed by a surface oxidation of said metal layer.

24. The organic light emitting diode according to claim 21 wherein said metal oxide layer is a AgO_x layer.

25. The organic light emitting diode according to claim 21 wherein said conductive layer further comprises an conductive polymer layer formed on said metal oxide layer.

26. The organic light emitting diode according to claim 25 wherein said conductive polymer layer is one selected from a group consisting of layers of polyethylene dioxythiophene/polystyrene sulphonate (PEDOT/PSS), 4, 4′

, 4″

-tris(3-methylphenylphenylamino)triphenylamine (m-MTDATA), and polyaniline (PANI), stack layers thereof and a layer of a mixture thereof.

27. The organic light emitting diode according to claim 20 wherein said conductive layer further comprises an conductive polymer layer formed on said metal layer.

28. The organic light emitting diode according to claim 27 wherein said conductive polymer layer is one selected from a group consisting of layers of polyethylene dioxythiophene/polystyrene sulphonate (PEDOT/PSS), 4, 4′

, 4″

-tris(3-methylphenylphenylamino)triphenylamine (m-MTDATA), and polyaniline (PANI), stack layers thereof and a layer of a mixture thereof.

29. An organic light emitting diode, comprising:

a substrate;

a first electrode structure formed on said substrate and comprising at least a metal layer and an opaque metal oxide layer;

an organic layer formed on said first electrode structure; and

a second electrode structure formed on said organic layer.

30. An organic light emitting diode, comprising:

a substrate;

a metal layer formed on said substrate;

a metal oxide layer formed on said metal layer and formed by oxidizing a surface of said metal layer;

an organic layer formed on said metal oxide layer; and

an electrode structure formed on said organic layer.