Alternating current light-emitting device

• US 7,544,524 B2
• Filed: 05/12/2006
• Issued: 06/09/2009
• Est. Priority Date: 05/13/2005
• Status: Active Grant

• Current Assignee: Epistar Corporation
• Original Assignee: Industrial Technology Research Institute
• Inventors: Lin, Ming-Yao, Yeh, Wen-Yung, Lin, Ming-Te, Yen, Hsi-Hsuan, Huang, Sheng-Pan
• Primary Examiner(s): LEE, HSIEN MING
• Application Number:
  US11/432,366
• Publication Number:
  US 20070080355A1
• Time in Patent Office: 1,124 Days
• Field of Search: 438 22- 29
• US Class Current: 438/22
• CPC Class Codes: H01L 25/0753 the devices being arranged next to each other
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00
• CPC Class Codes: H05B 45/00 Circuit arrangements for operating light-emitting diodes [LED]
• CPC Class Codes: H05B 45/30 Driver circuits
• CPC Class Codes: H05B 45/40 Details of LED load circuits

Abstract

An alternating current light-emitting device and the fabrication method thereof is disclosed. The alternating current light-emitting device includes at least one alternating current micro-die light-emitting module formed on a substrate and composed of at least two micro-dies connected to one another. The micro-dies, each includes at least two active layers, are electrically connected by a conductive structure, such that the active layers of the micro-dies take turns emitting light during positive and negative half cycles of alternating current, thereby providing a full-scale light-emitting area for all-time light emission.

Claims

1. A fabrication method for an alternating current light-emitting device, the fabrication method comprising the steps of:

providing a substrate;

forming at least two active layers on the substrate;

forming a plurality of openings in the active layers such that a portion of the substrate is exposed through the openings;

covering a periphery of the active layers with a protective layer;

forming a plurality of conductive terminals through the protection layer so as to electrically connect to the active layers; and

forming a plurality of conductive structures on the exposed portions of the substrate in the openings, the conductive structures providing electrical connection with the active layers such that, after alternating current is applied to the active layers, the active layers take turns to emit light during positive and negative half cycles of alternating current.

2. The fabrication method of the alternating current light-emitting device of claim 1, wherein the substrate is a chip.

3. The fabrication method of the alternating current light-emitting device of claim 1, wherein the substrate is an insulating substrate.

4. The fabrication method of the alternating current light-emitting device of claim 1, wherein the active layer is a luminescent active layer.

5. The fabrication method of the alternating current light-emitting device of claim 1, wherein the conductive structure comprise a conductor connecting the active layers flanking each of the openings.

6. The fabrication method of the alternating current light-emitting device of claim 5, wherein the conductor is a conductive bridge.

7. The fabrication method of the alternating current light-emitting device of claim 1, wherein the conductive terminals and the active layers are electrically connected so as to form a micro-die thereafter.

8. The fabrication method of the alternating current light-emitting device of claim 7, wherein the micro-dies emit light at identical wavelengths.

9. The fabrication method of the alternating current light-emitting device of claim 7, wherein the micro-dies emit light at different wavelengths.

10. The fabrication method of the alternating current light-emitting device of claim 7, wherein the active layers of the micro-dies emit light at identical wavelengths.

11. The fabrication method of the alternating current light-emitting device of claim 7, wherein the active layers of the micro-dies emit light at different wavelengths.

12. The fabrication method of the alternating current light-emitting device of claim 7, wherein the active layers of the micro-dies emit light at identical wavelengths and take turns to emit light during the positive and negative half cycles of alternating current.

13. The fabrication method of the alternating current light-emitting device of claim 7, wherein the active layers of the micro-dies emit light at different wavelengths and take turns to emit light during the positive and negative half cycles of alternating current.

14. The fabrication method of the alternating current light-emitting device of claim 1, wherein the conductive terminals are formed by vapor deposition.

15. The fabrication method of the alternating current light-emitting device of claim 1, wherein the conductive terminals are ohmic electrodes.

16. The fabrication method of the alternating current light-emitting device of claim 1, wherein the at least two active layers on the substrate are formed in sequence by epitaxy technology.

17. The fabrication method of the alternating current light-emitting device of claim 1, wherein the plurality of openings are formed in the active layers by lithography and etching.

18. The fabrication method of the alternating current light-emitting device of claim 1, wherein the protective layer is made of a dielectric material.

19. The fabrication method of the alternating current light-emitting device of claim 18, wherein the dielectric material is one of SiO_x and SiN_x.

20. A fabrication method for an alternating current light-emitting device, the fabrication method comprising the steps of:

providing a first substrate;

forming a first active layer on the first substrate;

removing the first substrate, and disposing the first active layer on a second substrate;

forming a second active layer on the first active layer, and forming a connection layer between the first active layer and the second active layer;

forming a plurality of openings in the first active layer and the second active layer such that a portion of the second substrate is exposed through the openings;

covering a periphery of the first active layer and the second active layer with a protective layer;

forming a plurality of conductive terminals through the protective layer to electrically connect to the first active layer and the second active layer; and

forming on the openings a plurality of conductive structures for electrical connection with the first active layer and the second active layer such that, after alternating current is applied to the first active layer and the second active layer, the first active layer and the second active layer take turns to emit light during positive and negative half cycles of alternating current.

21. The fabrication method of the alternating current light-emitting device of claim 20, wherein the first substrate is a chip.

22. The fabrication method of the alternating current light-emitting device of claim 20, wherein the first substrate is an insulating substrate.

23. The fabrication method of the alternating current light-emitting device of claim 20, wherein the second substrate is an insulating substrate.

24. The fabrication method of the alternating current light-emitting device of claim 20, wherein the first active layer is a luminescent active layer.

25. The fabrication method of the alternating current light-emitting device of claim 20, wherein the second active layer is a luminescent active layer.

26. The fabrication method of the alternating current light-emitting device of claim 20, wherein the conductive structures comprise a conductor connecting the first active layer and the second active layer flanking each of the openings.

27. The fabrication method of the alternating current light-emitting device of claim 26, wherein the conductor is a conductive bridge.

28. The fabrication method of the alternating current light-emitting device of claim 20, wherein the conductive terminals, the first active layer, and the second active layer are electrically connected to one another so as to form a micro-die thereafter.

29. The fabrication method of the alternating current light-emitting device of claim 28, wherein the micro-dies emit light at identical wavelengths.

30. The fabrication method of the alternating current light-emitting device of claim 28, wherein the micro-dies emit light at different wavelengths.

31. The fabrication method of the alternating current light-emitting device of claim 28, wherein the first active layer and the second active layer of the micro-die emit light at identical wavelengths.

32. The fabrication method of the alternating current light-emitting device of claim 28, wherein the first active layer and the second active layer of the micro-die emit light at different wavelengths.

33. The fabrication method of the alternating current light-emitting device of claim 28, wherein the first active layer and the second active layer of the micro-dies take turns to emit light during the positive and negative half cycles of alternating current.

34. The fabrication method of the alternating current light-emitting device of claim 28, wherein the first active layer and the second active layer of adjacent micro-dies take turns to emit light during the positive and negative half cycles of alternating current.

35. The fabrication method of the alternating current light-emitting device of claim 20, wherein the conductive terminals are formed by vapor deposition.

36. The fabrication method of the alternating current light-emitting device of claim 20, wherein the conductive terminals are ohmic electrodes.

37. The fabrication method of the alternating current light-emitting device of claim 20, wherein the connection layer is made of a material selected from the group consisting of a conductive material and a non-conductive material.

38. The fabrication method of the alternating current light-emitting device of claim 37, wherein the connection layer is made of a material previous to light.

39. The fabrication method of the alternating current light-emitting device of claim 20, wherein the plurality of openings are formed in the first active layer and the second active layer by lithography and etching.

40. The fabrication method of the alternating current light-emitting device of claim 20, wherein the protective layer is made of a dielectric material.

41. The fabrication method of the alternating current light-emitting device of claim 40, wherein the dielectric material is one of SiO_x and SiN_x.

42. A fabrication method for an alternating current light-emitting device, the fabrication method comprising the steps of:

providing a substrate;

forming at least two active layers on the substrate, the at least two active layers comprising a first active layer formed on the substrate and a second active layer formed on the first active layer;

forming a plurality of openings in the active layers such that a portion of the substrate is exposed through the openings;

covering a periphery of the active layers with a protective layer;

forming a plurality of conductive terminals through the protection layer so as to electrically connect to the active layers; and

forming on the exposed portions of the substrates in the openings a plurality of conductive structures for electrical connection with the active layers such that, after alternating current is applied to the active layers, the active layers take turns to emit light during positive and negative half cycles of alternating current.

43. The fabrication method of the alternating current light-emitting device of claim 42, wherein the substrate is a chip.

44. The fabrication method of the alternating current light-emitting device of claim 42, wherein the substrate is an insulating substrate.

45. The fabrication method of the alternating current light-emitting device of claim 42, wherein the active layer is a luminescent active layer.

46. The fabrication method of the alternating current light-emitting device of claim 42, wherein the conductive structures comprise a conductor connecting the active layers flanking each of the openings.

47. The fabrication method of the alternating current light-emitting device of claim 46, wherein the conductor is a conductive bridge.

48. The fabrication method of the alternating current light-emitting device of claim 42, wherein the conductive terminals and the active layers are electrically connected so as to form a micro-die thereafter.

49. The fabrication method of the alternating current light-emitting device of claim 48, wherein the micro-dies emit light at identical wavelengths.

50. The fabrication method of the alternating current light-emitting device of claim 48, wherein the micro-dies emit light at different wavelengths.

51. The fabrication method of the alternating current light-emitting device of claim 48, wherein the active layers of the micro-dies emit light at identical wavelengths.

52. The fabrication method of the alternating current light-emitting device of claim 48, wherein the active layers of the micro-dies emit light at different wavelengths.

53. The fabrication method of the alternating current light-emitting device of claim 48, wherein the active layers of the micro-dies emit light at identical wavelenghts and take turns to emit light during the positive and negative half cycles of alternating current.

54. The fabrication method of the alternating current light-emitting device of claim 48, wherein the active layers of the micro-dies emit light at different wavelenghths and take turns to emit light during the positive and negative half cycles of alternating current.

55. The fabrication method of the alternating current light-emitting device of claim 42, wherein the conductive terminals are formed by vapor deposition.

56. The fabrication method of the alternating current light-emitting device of claim 42, wherein the conductive terminals are ohmic electrodes.

57. The fabrication method of the alternating current light-emitting device of claim 42, wherein the at least two active layers on the substrate are formed in sequence by epitaxy technology.

58. The fabrication method of the alternating current light-emitting device of claim 42, wherein the plurality of openings are formed in the active layers by lithography and etching.

59. The fabrication method of the alternating current light-emitting device of claim 42, wherein the protective layer is made of a dielectric material.

60. The fabrication method of the alternating current light-emitting device of claim 59, wherein the dielectric material is one of SiO_x and SIN_x.