Visible light emitting diodes fabricated from soluble semiconducting polymers

• US 6,878,974 B2
• Filed: 08/20/2002
• Issued: 04/12/2005
• Est. Priority Date: 02/27/1991
• Status: Expired due to Fees

• Current Assignee: Regents of the University of California (University of California)
• Original Assignee: Regents of the University of California (University of California)
• Inventors: Braun, David, Heeger, Alan J.
• Primary Examiner(s): FOURSON III, GEORGE R
• Application Number:
  US10/223,917
• Publication Number:
  US 20020197755A1
• Time in Patent Office: 966 Days
• Field of Search: 257/103, 257/E33.061, 257/E33.063, 257/E33.064, 313/498, 313/499
• US Class Current: 257/103
• CPC Class Codes: H10K 2102/311 Flexible OLED
• CPC Class Codes: H10K 50/11 characterised by the electroluminescent [EL] layers
• CPC Class Codes: H10K 50/805 Electrodes
• CPC Class Codes: H10K 50/81 Anodes
• CPC Class Codes: H10K 50/82 Cathodes
• CPC Class Codes: H10K 50/868 Arrangements for polarized light emission H10K50/86 takes precedence
• CPC Class Codes: H10K 71/00 Manufacture or treatment specially adapted for the organic devices covered by this subclass
• CPC Class Codes: H10K 71/191 characterised by provisions for the orientation or alignment of the layer to be deposited
• CPC Class Codes: H10K 85/114 Poly-phenylenevinylene; Derivatives thereof

Abstract

Visible light LEDs are produced having a layer of conjugated polymer which is cast directly from solution or formed as a gel-processed admixture with a carrier polymer. The LEDs can be formed so as to emit polarized light.

Claims

1. A light-emitting diode which emits visible light and which turns on at voltages below 5 volts, comprising:

i) a substrate;

ii) a transparent conducting first layer coated onto said substrate, said first layer having high work function and serving as a hole-injecting electrode;

iii) a transparent layer of a soluble semiconducting luminescent conjugated polymer fabricated onto the transparent conducting first layer; and

iv) an electron-injecting contact fabricated from a low work function metal onto the semiconducting conjugated polymer layer.

2. The light-emitting diode of claim 1, wherein the substrate is a transparent, inorganic substrate.

3. The light-emitting diode of claim 1, wherein the substrate is a transparent, organic polymer substrate.

4. The light-emitting diode of claim 1, wherein the conducting first layer is an electronegative metal.

5. The light-emitting diode of claim 1, wherein the conducting first layer is a conductive metal-metal oxide mixture.

6. The light-emitting diode of claim 1, wherein the semiconducting conjugated polymer layer comprises poly(2-methoxy,5-(2′

-ethylhexyloxy)-1,4-phenylenevinylene).

7. The light-emitting diode of claim 1, wherein the semiconducting conjugated polymer layer comprises a semiconducting conjugated polymer selected from the group consisting of soluble alkoxy derivatives of poly(phenylenevinylene).

8. The light-emitting diode of claim 1, wherein the conducting first layer comprises gold or silver.

9. The light-emitting diode of claim 1, wherein the conducting first layer comprises indium-tin oxide.

10. The light-emitting diode of claim 1, wherein the substrate comprises an organic polymer selected from the group consisting of polyesters, polycarbonates, polyacrylates, and polystyrenes.

11. A light-emitting diode which emits visible light and which turns on at voltages below 5 volts, comprising:

i) a substrate;

ii) a transparent conducting first layer coated onto said substrate, said first layer having high work function and serving as a hole-injecting electrode;

iii) a transparent layer of a soluble semiconducting luminescent conjugated polymer fabricated onto the transparent conducting first layer; and

iv) an electron-injecting contact fabricated from calcium or a lower work function alkaline earth metal onto the semiconducting conjugated polymer layer.

12. The light-emitting diode of claim 11, wherein the substrate is a transparent, inorganic substrate.

13. The light-emitting diode of claim 11, wherein the substrate is a transparent, organic polymer substrate.

14. The light-emitting diode of claim 11, wherein the substrate comprises an organic polymer selected from the group consisting of polyesters, polycarbonates, polyacrylates, and polystyrenes.

15. The light-emitting diode of claim 11, wherein the conducting first layer is a conductive metal-metal oxide mixture.

16. The light-emitting diode of claim 11, wherein the conducting first layer comprises indium-tin oxide.

17. The light-emitting diode of claim 11, wherein the conducting first layer is an electronegative metal.

18. The light-emitting diode of claim 11, wherein the conducting first layer comprises gold or silver.

19. The light-emitting diode of claim 11, wherein the semiconducting conjugated polymer layer comprises a semiconducting conjugated polymer selected from the group consisting of soluble alkoxy derivatives of poly (phenylenevinylene).

20. The light-emitting diode of claim 11, wherein the semiconducting conjugated polymer layer comprises poly(2-methoxy,5-(2′

-ethylhexyloxy)-1,4-phenylenevinylene).

21. The light-emitting diode of claim 11, wherein electron-injecting contact is calcium.

22. The light-emitting diode of claim 11, wherein electron-injecting contact is barium.

23. A light-emitting diode which emits visible light and which turns on at voltages below 5 volts, comprising:

i) a substrate;

ii) a transparent conducting first layer coated onto said substrate, said first layer having high work function and serving as a hole-injecting electrode;

iii) a transparent layer of a soluble semiconducting luminescent conjugated polymer fabricated onto the transparent conducting first layer; and

iv) an electron-injecting contact fabricated from calcium onto the semiconducting conjugated polymer layer.

24. The light-emitting diode of claim 23, wherein the substrate is a transparent, inorganic substrate.

25. The light-emitting diode of claim 23, wherein the substrate is transparent, organic polymer substrate.

26. The light-emitting diode of claim 23, wherein the substrate comprises an organic polymer selected from the group consisting of polyesters, polycarbonates, polyacrylates, and polystyrenes.

27. The light-emitting diode of claim 23, wherein the conducting first layer is a conductive metal-metal oxide mixture.

28. The light-emitting diode of claim 23, wherein the conducting first layer comprises indium-tin oxide.

29. The light-emitting diode of claim 23, wherein the conducting first layer is an electronegative metal.

30. The light-emitting diode of claim 23, wherein the conducting first layer comprises gold or silver.

31. The light-emitting diode of claim 23, wherein the semiconducting conjugated polymer layer comprises poly(2-methoxy,5-(2′

-ethylhexyloxy)-1,4-phenylenevinylene).

32. A light-emitting diode which emits visible light and which turns on at voltages below 5 volts, comprising:

i) a substrate;

ii) a transparent conducting first layer coated onto said substrate, said first layer having high work function and serving as a hole-injecting electrode;

iii) a transparent layer of a soluble semiconducting luminescent conjugated polymer fabricated onto the transparent conducting first layer; and

iv) an electron-injecting contact fabricated from barium onto the semiconducting conjugated polymer layer.

33. The light-emitting diode of claim 32, wherein the substrate is a transparent, inorganic substrate.

34. The light-emitting diode of claim 32, wherein the substrate is a transparent, organic polymer substrate.

35. The light-emitting diode of claim 32, wherein the substrate comprises an organic polymer selected from the group consisting of polyesters, polycarbonates, polyacrylates, and polystyrenes.

36. The light-emitting diode of claim 32, wherein the conducting first layer is a conductive metal-metal oxide mixture.

37. The light-emitting diode of claim 32, wherein the conducting first layer comprises indium-tin oxide.

38. The light-emitting diode of claim 32, wherein the conducting first layer is an electronegative metal.

39. The light-emitting diode of claim 32, wherein the conducting first layer comprises gold or silver.

40. The light-emitting diode of claim 32, wherein the semiconducting conjugated polymer layer comprises poly(2-methoxy,5-(2′

-ethylhexyloxy)-1,4-phenylenevinylene).

41. A light-emitting diode which emits visible light and which turns on at voltages below 5 volts, comprising:

i) a substrate;

ii) a transparent conducting first layer coated onto said substrate, said first layer having high work function and serving as a hole-injecting electrode;

iii) a transparent layer of a soluble semiconducting luminescent conjugated polymer selected from the group consisting of soluble alkoxy derivatives of poly(phenylenevinylene) fabricated onto the transparent conducting first layer; and

iv) an electron-injecting contact fabricated from calcium or a lower work function alkaline earth metal onto the semiconducting conjugated polymer layer.

42. The light-emitting diode of claim 41, wherein the substrate is a transparent, inorganic substrate.

43. The light-emitting diode of claim 41, wherein the substrate is a transparent, organic polymer substrate.

44. The light-emitting diode of claim 41, wherein the substrate comprises an organic polymer selected from the group consisting of polyesters, polycarbonates, polyacrylates, and polystyrenes.

45. The light-emitting diode of claim 41, wherein the conducting first layer is a conductive metal-metal oxide mixture.

46. The light-emitting diode of claim 41, wherein the conducting first layer comprises indium-tin oxide.

47. The light-emitting diode of claim 41, wherein the conducting first layer is an electronegative metal.

48. The light-emitting diode of claim 41, wherein the conducting first layer comprises gold or silver.

49. The light-emitting diode of claim 41, wherein the semiconducting conjugated polymer layer comprises poly(2-methoxy,5-(2′

-ethylhexyloxy)-1,4-phenyenevinylene).

50. The light-emitting diode of claim 41, wherein the electron-injecting contact is calcium.

51. The light-emitting diode of claim 41, wherein the electron-injecting contact is barium.

52. A light-emitting diode which emits visible light and which turns on at voltages below 5 volts, comprising:

i) a substrate;

ii) a transparent conducting first layer coated onto said substrate, said first layer having high work function and serving as a hole-injecting electrode;

iii) a transparent layer of a soluble semiconducting luminescent conjugated polymer selected from the group consisting of soluble alkoxy derivatives of poly(phenylenevinylene) fabricated onto the transparent conducting first layer; and

iv) an electron-injecting contact fabricated from calcium onto the semiconducting conjugated polymer layer.

53. The light-emitting diode of claim 52, wherein the substrate is a transparent, inorganic substrate.

54. The light-emitting diode of claim 52, wherein the substrate is a transparent, organic polymer substrate.

55. The light-emitting diode of claim 52, wherein the substrate comprises an organic polymer selected from the group consisting of polyesters, polycarbonates, polyacrylates, and polystyrenes.

56. The light-emitting diode of claim 52, wherein the conducting first layer is a conductive metal-metal oxide mixture.

57. The light-emitting diode of claim 52, wherein the conducting first layer comprises indium-tin oxide.

58. The light-emitting diode of claim 52, wherein the conducting first layer is an electronegative metal.

59. The light-emitting diode of claim 52, wherein the conducting first layer comprises gold or silver.

60. The light-emitting diode of claim 52, wherein the semiconducting conjugated polymer layer comprises poly(2-methoxy,5-(2′

-ethylhexyloxy)-1,4-phenylenevinylene).

61. A light-emitting diode which emits visible light and which turns on at voltages below 5 volts, comprising:

i) a substrate;

ii) a transparent conducting first layer coated onto said substrate, said first layer having high work function and serving as a hole-injecting electrode;

iii) a transparent layer of a soluble semiconducting luminescent conjugated polymer selected from the group consisting of soluble alkoxy derivatives of poly(phenylenevinylene) fabricated onto the transparent conducting first layer; and

iv) an electron-injecting contact fabricated from barium onto the semiconducting conjugated polymer layer.

62. The light-emitting diode of claim 61, wherein the substrate is a transparent, inorganic substrate.

63. The light-emitting diode of claim 61, wherein the substrate is a transparent, organic polymer substrate.

64. The light-emitting diode of claim 61, wherein the substrate comprises an organic polymer selected from the group consisting of polyesters, polycarbonates, polyacrylates, and polystyrenes.

65. The light-emitting diode of claim 61, wherein the conducting fist layer is a conductive metal-metal oxide mixture.

66. The light-emitting diode of claim 61, wherein the conducting first layer comprises indium-tin oxide.

67. The light-emitting diode of claim 61, wherein the conducting first layer is an electronegative metal.

68. The light-emitting diode of claim 61, wherein the conducting first layer comprises gold or silver.

69. The light-emitting diode of claim 61, wherein the semiconducting conjugated polymer layer comprises poly(2-methoxy,5-(2′

-ethylhexyloxy)-1,4-phenylenevinylene).