Alternating current light-emitting device

• US 20070080355A1
• Filed: 05/12/2006
• Published: 04/12/2007
• 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
• Granted Patent: US 7,544,524 B2
• Time in Patent Office: Days
• US Class Current: 257/81
• 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. An alternating current light-emitting device, comprising:

a substrate;

an alternating current micro-die light-emitting module formed on the substrate and having at least two micro-dies, each micro-die having at least two active layers; and

a conductive structure electrically connecting the micro-dies such that the active layers of the micro-dies take turns to emit light during positive and negative half cycles of alternating current.

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

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

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

5. The alternating current light-emitting device of claim 1, wherein the conductive structure comprises a conductor disposed between and connecting the two micro-dies.

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

7. The alternating current light-emitting device of claim 1, wherein electrical connections between the micro-dies and the active layers thereof comprise series connections and parallel connections.

8. The alternating current light-emitting device of claim 1, wherein the micro-dies emit light at identical wavelengths.

9. The alternating current light-emitting device of claim 1, wherein the micro-dies emit light at different wavelengths.

10. The alternating current light-emitting device of claim 1, wherein the active layers of the micro-dies emit light at identical wavelengths.

11. The alternating current light-emitting device of claim 1, wherein the active layers of the micro-dies emit light at different wavelengths.

12. The alternating current light-emitting device of claim 1, wherein the active layers of the micro-dies have their respective ohmic electrodes.

13. The alternating current light-emitting device of claim 1, wherein the identical active layers of the micro-dies take turns to emit light during the positive and negative half cycles of alternating current.

14. The alternating current light-emitting device of claim 1, wherein the different active layers of the micro-dies take turns to emit light during the positive and negative half cycles of alternating current.

15. The alternating current light-emitting device of claim 1, wherein the micro-dies, each having the at least two active layers, are fabricated by one of flip-chip technology and wafer bonding teleology.

16. The alternating current light-emitting device of claim 1, wherein the micro-dies, each having the at least two active layers, are fabricated by epitaxy technology.

17. An alternating current light-emitting device, comprising:

a substrate;

a plurality of alternating current micro-die light-emitting modules formed on the substrate, each alternating current micro-die light-emitting module having at least two micro-dies, each micro-die having at least two active layers; and

a conductive structure electrically connecting the alternating current micro-die light-emitting modules and the micro-dies respectively such that the active layers of the micro-dies take turns to emit light during positive and negative half cycles of alternating current.

18. The alternating current light-emitting device of claim 17, wherein the substrate is a chip.

19. The alternating current light-emitting device of claim 17, wherein the substrate is an insulating substrate.

20. The alternating current light-emitting device of claim 17, wherein the active layer is a luminescent active layer.

21. The alternating current light-emitting device of claim 17, wherein the conductive structure comprises a conductor disposed between and connecting the two alternating current micro-die light-emitting modules and a conductor disposed between and connecting the two micro-dies.

22. The alternating current light-emitting device of claim 21, wherein the conductor is a conductive bridge.

23. The alternating current light-emitting device of claim 17, wherein the alternating current micro-die light-emitting modules are connected to one another in series.

24. The alternating current light-emitting device of claim 17, wherein electrical connections between the micro-dies and the active layers thereof comprise series connections and parallel connections.

25. The alternating current light-emitting device of claim 17, wherein the micro-dies emit light at identical wavelengths.

26. The alternating current light-emitting device of claim 17, wherein the micro-dies emit light at different wavelengths.

27. The alternating current light-emitting device of claim 17, wherein the active layers of the micro-dies have their respective ohmic electrodes.

28. The alternating current light-emitting device of claim 17, wherein the identical active layers of the micro-dies takes turns to emit light during the positive and negative half cycles of alternating current.

29. The alternating current light-emitting device of claim 17, wherein the different active layers of the micro-dies takes turns to emit light during the positive and negative half cycles of alternating current.

30. The alternating current light-emitting device of claim 17, wherein the micro-dies, each having the at least two active layers, are fabricated by one of flip-chip technology and wafer bonding technology.

31. The alternating current light-emitting device of claim 17, wherein the micro-dies, each having the at least two active layers, are fabricated by epitaxy technology.

32. The alternating current light-emitting device of claim 17, wherein the at least one active layer of each of the micro-dies is disposed in accordance with a pattern of a diode circuit in a bridge rectifier and is electrically connected to one another so as to form a bridge light-emitting unit.

33. The alternating current light-emitting device of claim 17, wherein the at least one active layer of each of the micro-dies is disposed in accordance with a pattern of a diode circuit in a bridge rectifier and is electrically connected to one another so as to form a plurality of bridge light-emitting units.

34. The alternating current light-emitting device of claim 33, wherein the bridge light-emitting micro-dies are disposed in a matrix-like pattern, and all-time light-emitting micro-dies in a central region are more than rectified light-emitting micro-dies in a peripheral region.

35. The alternating current light-emitting device of claim 33, further comprising conductive electrodes disposed at two opposite diagonal corners of the matrix-like pattern and connected to the bridge light-emitting units in series for connection with an alternating current source.

36. 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 on 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.

37. The fabrication method of the alternating current light-emitting device of claim 36, wherein the substrate is a chip.

38. The fabrication method of the alternating current light-emitting device of claim 36, wherein the substrate is an insulating substrate.

39. The fabrication method of the alternating current light-emitting device of claim 36, wherein the active layer is a luminescent active layer.

40. The fabrication method of the alternating current light-emitting device of claim 36, wherein the conductive structure comprises a conductor connecting the active layers flanking each of the openings.

41. The fabrication method of the alternating current light-emitting device of claim 40, wherein the conductor is a conductive bridge.

42. The fabrication method of the alternating current light-emitting device of claim 36, wherein the conductive terminals and the active layers are electrically connected so as to form a micro-die thereafter.

43. The fabrication method of the alternating current light-emitting device of claim 42, wherein the micro-dies emit light at identical wavelengths.

44. The fabrication method of the alternating current light-emitting device of claim 42, wherein the micro-dies emit light at different wavelengths.

45. The fabrication method of the alternating current light-emitting device of claim 42, wherein the active layers of the micro-dies emit light at identical wavelengths.

46. The fabrication method of the alternating current light-emitting device of claim 42, wherein the active layers of the micro-dies emit light at different wavelengths.

47. The fabrication method of the alternating current light-emitting device of claim 42, wherein the identical active layers of the micro-dies takes turns to emit light during the positive and negative half cycles of alternating current.

48. The fabrication method of the alternating current light-emitting device of claim 42, wherein the different active layers of the micro-dies takes turns to emit light during the positive and negative half cycles of alternating current.

49. The fabrication method of the alternating current light-emitting device of claim 36, wherein the conductive terminals are formed by vapor deposition.

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

51. The fabrication method of the alternating current light-emitting device of claim 36, wherein the at least two active layers on the substrate are formed in sequence by epitaxy technology.

52. The fabrication method of the alternating current light-emitting device of claim 36, wherein the plurality of openings are formed in the active layers by lithography and etching.

53. The fabrication method of the alternating current light-emitting device of claim 36, wherein the protective layer is made of a dielectric material.

54. The fabrication method of the alternating current light-emitting device of claim 53, wherein the dielectric material is one of SiO_x and SiN_x.

55. 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 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.

56. The fabrication method of the alternating current light-emitting device of claim 55, wherein the first substrate is a chip.

57. The fabrication method of the alternating current light-emitting device of claim 55, wherein the first substrate is an insulating substrate.

58. The fabrication method of the alternating current light-emitting device of claim 55, wherein the second substrate is an insulating substrate.

59. The fabrication method of the alternating current light-emitting device of claim 55, wherein the first active layer is a luminescent active layer.

60. The fabrication method of the alternating current light-emitting device of claim 55, wherein the second active layer is a luminescent active layer.

61. The fabrication method of the alternating current light-emitting device of claim 55, wherein the conductive structure comprises a conductor connecting the first active layers and the second active layers flanking each of the openings.

62. The fabrication method of the alternating current light-emitting device of claim 61, wherein the conductor is a conductive bridge.

63. The fabrication method of the alternating current light-emitting device of claim 55, 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.

64. The fabrication method of the alternating current light-emitting device of claim 63, wherein the micro-dies emit light at identical wavelengths.

65. The fabrication method of the alternating current light-emitting device of claim 63, wherein the micro-dies emit light at different wavelengths.

66. The fabrication method of the alternating current light-emitting device of claim 63, wherein the first active layer and the second active layer of the micro-die emit light at identical wavelengths.

67. The fabrication method of the alternating current light-emitting device of claim 63, wherein the first active layer and the second active layer of the micro-die emit light at different wavelengths.

68. The fabrication method of the alternating current light-emitting device of claim 63, wherein the first active layers and the second active layers of the micro-dies take turns to emit light during the positive and negative half cycles of alternating current.

69. The fabrication method of the alternating current light-emitting device of claim 63, wherein the first active layers and the second active layers of the adjacent micro-dies take turns to emit light during the positive and negative half cycles of alternating current, using different layers.

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

71. The fabrication method of the alternating current light-emitting device of claim 55, wherein the conductive terminals are ohmic electrodes.

72. The fabrication method of the alternating current light-emitting device of claim 55, wherein the connection layer is made of a material selected from the group consisting of a conductive material and a non-conductive material.

73. The fabrication method of the alternating current light-emitting device of claim 72, wherein the connection layer is made of a material previous to light.

74. The fabrication method of the alternating current light-emitting device of claim 55, wherein the plurality of openings are formed in the first active layer and the second active layer by lithography and etching.

75. The fabrication method of the alternating current light-emitting device of claim 55, wherein the protective layer is made of a dielectric material.

76. The fabrication method of the alternating current light-emitting device of claim 75, wherein the dielectric material is one of SiO_x and SiN_x.

77. An alternating current light-emitting device, comprising:

a substrate;

a bridge light-emitting unit comprising a plurality of alternating current light-emitting diode micro-dies fonned on the substrate, the micro-dies being disposed in accordance with a pattern of a diode circuit in a bridge rectifier; and

a conductive structure electrically connected to the micro-dies such that the micro-dies take turns to emit light during positive and negative half cycles of alternating current.

78. The alternating current light-emitting device of claim 77, comprising more than one bridge light-emitting units electrically connected to one another, wherein the bridge light-emitting micro-dies are disposed in a matrix-like pattern, and all-time light-emitting micro-dies in a central region are more than rectified light-emitting micro-dies in a peripheral region.

79. The alternating current light-emitting device of claim 78, further comprising conductive electrodes disposed at two opposite diagonal corners of the matrix-like pattern and connected to the bridge light-emitting units in series for connection with an alternating current source.

80. The alternating current light-emitting device of claim 77, wherein the substrate is a chip.

81. The alternating current light-emitting device of claim 77, wherein the substrate is an insulating substrate.

82. The alternating current light-emitting device of claim 77, wherein the conductive structure comprises a conductor disposed between and connecting the two micro-dies.

83. The alternating current light-emitting device of claim 82, wherein the conductor is a conductive bridge.

84. The alternating current light-emitting device of claim 77, wherein the micro-dies emit light at identical wavelengths.