Alternating current light-emitting device

• US 20060256826A1
• Filed: 10/07/2005
• Published: 11/16/2006
• Est. Priority Date: 05/13/2005
• Status: Active Grant

• Current Assignee: Epistar Corporation
• Original Assignee: Industrial Technology Research Institute
• Inventors: Lin, MIng-Te, Lin, Ming-Yao, Yeh, Wen-Yung, Yen, Hsi-Hsuan, Huang, Sheng-Pan
• Granted Patent: US 7,474,681 B2
• Time in Patent Office: Days
• US Class Current: 372/43.10
• CPC Class Codes: F21K 9/00 Light sources using semiconductor devices as light-generating elements, e.g. using light-emitting diodes [LED] or lasers
• CPC Class Codes: H01L 25/0753 the devices being arranged next to each other
• CPC Class Codes: H01L 27/156 two-dimensional arrays
• 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: H01L 33/62 Arrangements for conducting electric current to or from the semiconductor body, e.g. lead-frames, wire-bonds or solder balls

Abstract

An alternating current light emitting device and the fabrication method includes forming one or more alternating current micro diode light emitting modules on a substrate, wherein the alternating current micro diode light emitting module has two micro diodes connected to one another, and each micro diode has at least two active layers and is electrically connected by a conductive structure, such that the active layers of each micro diode can take turns emitting light during the positive/negative half cycles of alternating current. A continuous and full-scale light emitting effect is thereby achieved.

Claims

1. An alternating current light emitting device, comprising:

a substrate;

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

a conductive structure electrically connected to each micro diode so as to alternately 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 at least comprises a conductor connecting the two micro diodes.

6. The alternating current light emitting device of claim 1, wherein the conductive structure is a conductive bridge.

7. The alternating current light emitting device of claim 1, wherein the electrical connection between the micro diodes and the active layers includes a parallel connection and a serial connection.

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

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

10. The alternating current light emitting device of claim 1, wherein the active layer of the micro diode emit light of identical wavelength.

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

12. The alternating current light emitting device of claim 1, wherein the active layers of the micro diodes have individual ohm electrodes.

13. The alternating current light emitting device of claim 1, wherein the same active layers of the micro diodes alternately emit light during the positive and negative half cycles of alternating current.

14. The alternating current light emitting device of claim 1, wherein different active layers of the micro diodes alternately 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 diodes having at least two active layers are fabricated by a flip-chip or wafer bonding technique.

16. The alternating current light emitting device of claim 1, wherein the micro diodes having at least two active layers are fabricated by a chip-stacking technique.

31. The alternating current light emitting device of claim 1, wherein the micro diodes having at least two active layers are fabricated by a chip-stacking technique.

17. An alternating current light emitting device, comprising:

a substrate;

a plurality of alternating current micro diode light emitting modules formed on the substrate, wherein each alternating current micro diode light emitting module has at least two micro diodes, each micro diode having at least two active layers; and

a conductive structure respectively electrically connected to each alternating current micro diode light emitting module and each micro diode so as allow the active layers of the micro diodes to alternately 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 at least comprises a conductor connecting the two micro diode light emitting modules and a conductor connecting between the two micro diodes.

22. The alternating current light emitting device of claim 17, wherein the conductive structure is a conductive bridge.

23. The alternating current light emitting device of claim 17, wherein the electrical connection between the micro diode light emitting modules is a serial connection.

24. The alternating current light emitting device of claim 17, wherein the electrical connection between the micro diodes and the active layers comprises a serial connection and a parallel connection.

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

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

27. The alternating current light emitting device of claim 17, wherein the active layers of the micro diodes have individual ohm electrodes.

28. The alternating current light emitting device of claim 17, wherein the same active layers of the micro diodes 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 diodes 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 diodes having at least two active layers are fabricated by a flip-chip or wafer bonding technique.

32. The alternating current light emitting device of claim 17, wherein the circuit structure of the at least one active layer of the micro diode is arranged according to the arrangement of diodes in a bridge rectifier and electrically connected to form a bridge light emitting unit.

33. The alternating current light emitting device of claim 17, wherein the circuit structure of the at least one active layer of the micro diode is arranged according to the arrangement of diodes in a bridge rectifier and electrically connected to form a plurality of bridge light emitting units.

34. The alternating current light emitting device of claim 33, wherein each bridge light emitting unit is arrayed in a matrix, and the number of bridge light emitting units disposed in the central region is larger than that disposed in the peripheral regions.

35. The alternating current light emitting device of claim 34, further comprising conductive electrodes disposed on two diagonals of the matrix, and the conductive electrodes and the bridge light emitting units are serially connected to each other for connecting with alternating current.

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

preparing a substrate;

forming at least two active layers on the substrate;

forming a plurality of openings on each active layer;

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

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

forming a plurality of conductive structures on the openings so as to electrically connect to each active layer, such that application of alternating current to each of the active layers during usage will cause the layers to alternately 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 at least comprises a conductor connecting the active layers on two sides of the openings.

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

42. The fabrication method of the alternating current light emitting device of claim 36, wherein the conductive terminal and the active layer are electrically connected to form a micro diode.

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

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

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

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

47. The fabrication method of the alternating current light emitting device of claim 42, wherein the same active layers of the micro diodes alternately 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 different active layers of the micro diodes alternately 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 a steam-gilding technique.

50. The fabrication method of the alternating current light emitting device of claim 36, wherein the conductive terminals are ohm 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 by a chip-stacking technique.

52. The fabrication method of the alternating current light emitting device of claim 36, wherein the plurality of openings formed on the active layer are formed by yellow-light development and etching techniques.

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 36, wherein the dielectric material is selected from one of SiO_x or SiN_x.

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

preparing 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 on the first active layer and the second active layer to expose the substrate;

covering the outer 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 a plurality of conductive structures on the openings so as to electrically connect to the first active layer and the second active layer, such that application of alternating current to the first active layer and the second active layer will cause the layers to alternately 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 at least comprises a conductor connecting the first active layer and the second active layer on two sides of the openings.

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

63. The fabrication method of the alternating current light emitting device of claim 55, wherein the conductive terminal, the first active layer, and the second active layer are electrically connected to form a micro diode.

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

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

68. 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 diode alternately 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 layer and the second active layer adjacent to the micro diodes in different layers alternately emit light during the positive and negative half cycles of alternating current.

70. The fabrication method of the alternating current light emitting device of claim 55, wherein the conductive terminals are formed by a steam-gilding technique.

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

72. The fabrication method of the alternating current light emitting device of claim 55, wherein the connection layer is made of either conductive or 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 translucent to light.

74. The fabrication method of the alternating current light emitting device of claim 55, wherein the plurality of openings formed on the first active layer and the second active layer is formed by yellow-light development and etching techniques.

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 55, wherein the dielectric material is selected from one of SiO_x or SiN_x.

77. An alternating current light emitting device, which comprises at least:

a substrate;

a bridge light-emitting unit including a plurality of alternating current light emitting micro diodes, the micro diode being arranged based on a circuit structure of the diodes in a bridge rectifier; and

a conductive structure respectively electrically connected to the micro diodes so as to cause the diodes to alternately emit light during positive and negative half cycles of alternating current.

78. The alternating current light emitting device of claim 77, wherein the bridge light-emitting unit further comprises a plurality of bridge light emitting units electrically connected to one another, each bridge light emitting unit being arrayed in a matrix and a number of bridge light emitting units disposed in a central region being larger than a number disposed in a peripheral regions.

79. The alternating current light emitting device of claim 78, further comprising disposing conductive electrodes on two diagonals of the matrix, wherein the conductive electrodes and the bridge light emitting units are serially connected to each other for connecting with alternating current.

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 active layer is a luminescent active layer.

83. The alternating current light emitting device of claim 77, wherein the conductive structure at least comprises a conductor connecting the two micro diodes.

84. The alternating current light emitting device of claim 83, wherein the conductive structure is a conductive bridge.

85. The alternating current light emitting device of claim 77, wherein the micro diodes emit light of identical wavelengths.