Light-emitting apparatus

• US 20070200493A1
• Filed: 10/17/2006
• Published: 08/30/2007
• Est. Priority Date: 10/19/2005
• Status: Abandoned Application

• Current Assignee: Epistar Corporation (Ennostar, Inc.)
• Original Assignee: Epistar Corporation (Ennostar, Inc.)
• Inventors: Hsieh, Min-Hsun, Ou, Chen, Hsu, Tzu-Chieh, Liu, Mei-Chun, Tao, Ching-San, Wu, Mei-Lan
• Application Number:
  US11/581,439
• Publication Number:
  US 20070200493A1
• Time in Patent Office: Days
• US Class Current: 313/506
• CPC Class Codes: H01L 33/10 with a light reflecting structure, e.g. semiconductor Bragg reflector
• CPC Class Codes: H01L 33/20 with a particular shape, e.g. curved or truncated substrate
• CPC Class Codes: H01L 33/405 Reflective materials
• CPC Class Codes: H01L 33/42 Transparent materials

Abstract

The light-emitting apparatus comprises a substrate, a first semiconductor layer formed on the substrate, a light-emitting layer formed on the first semiconductor layer, a second semiconductor layer formed on the light-emitting layer, a first transparent conductive oxide layer formed on the second semiconductor layer, a reflective metal layer form on the transparent conductive oxide layer, and a first electrode formed on the reflective metal layer; characterized in that the first transparent conductive oxide layer is formed with a plurality of cavities on the interface between the first transparent conductive oxide layer and the reflective metal layer for improving the adhesion strength therebetween.

Claims

1. A light-emitting apparatus comprising:

a light-emitting stacked layer;

a first transparent conductive oxide layer formed on said light-emitting stacked layer, having a first surface facing said light-emitting stacked layer and a second surface with a first plurality of cavities; and

a first reflective metal layer formed on said first plurality of cavities of said first transparent conductive oxide layer.

2. The light-emitting apparatus according to claim 1, wherein said light-emitting stacked layer further comprises a second plurality of cavities in contact with said first transparent conductive oxide layer.

3. The light-emitting apparatus according to claim 2, wherein said first plurality of cavities is extended to said second plurality of cavities.

4. The light-emitting apparatus according to claim 1, wherein said light-emitting stacked layer comprises a first semiconductor layer;

a light-emitting layer formed on said first semiconductor layer; and

a second semiconductor layer formed on said light-emitting layer.

5. The light-emitting apparatus according to claim 1, further comprising a substrate formed below said light-emitting stacked layer.

6. The light-emitting apparatus according to claim 1, wherein said first transparent conductive oxide layer is selected form the group consisting of indium tin oxide (ITO), cadmium tin oxide (CTO), antimony tin oxide, zinc indium oxide, aluminum zinc oxide, zinc antimony oxide, and the combinations thereof.

7. The light-emitting apparatus according to claim 1, wherein the thickness of said transparent conductive oxide layer is from 50 nm to 1 um.

8. The light-emitting apparatus according to claim 6, wherein said substrate is selected form the group consisting of GaN, AlN, SiC, GaAs, GaP, Si, ZnO, MgO, MgAl₂O₄, glass, sapphire, and the combination thereof.

9. The light-emitting apparatus according to claim 1, wherein said light-emitting stacked layer is selected form the group consisting of AlGaInP, AlGaIn, GaInP, AlN, GaN, AlGaN, InGaN, AlInGaN, and the combination thereof.

10. The light-emitting apparatus according to claim 1, wherein said first plurality of cavities are formed by an etching process.

11. The light-emitting apparatus according to claim 2, wherein said second plurality of cavities are formed by an epitaxy process, an etching process, or the combination thereof.

12. The light-emitting apparatus according to claim 1, further comprising a first electrode formed on said first reflective metal layer.

13. The light-emitting apparatus according to claim 4, further comprising a second transparent conductive oxide layer with a third plurality of cavities formed on said first semiconductor layer.

14. The light-emitting apparatus according to claim 13, wherein said first semiconductor layer further comprises a fourth plurality of cavities in contact with second transparent conductive oxide layer.

15. The light-emitting apparatus according to claim 13, further comprising a second reflective metal layer formed on said second transparent conductive oxide layer and a second electrode formed on said second reflective metal layer.

16. The light-emitting apparatus according to claim 14, wherein said third plurality of cavities and said fourth plurality of cavities are formed by an etching process.

17. The light-emitting apparatus according to claim 13, wherein said second transparent conductive oxide layer is selected form the group consisting of indium tin oxide (ITO), cadmium tin oxide (CTO), antimony tin oxide, zinc indium oxide, aluminum zinc oxide, zinc antimony oxide, and the combinations thereof.

18. The light-emitting apparatus according to claim 15, wherein said first reflective metal layer and said second reflective metal layer are selected form the group consisting of Al, Ag, and the combinations thereof.

19. The light-emitting apparatus according to claim 5, further comprising a binding layer formed between said light-emitting stacked layer and said substrate.

20. The light-emitting apparatus according to claim 19, wherein said binding layer is a dielectric binding layer or a metal binding layer.

21. The light-emitting apparatus according to claim 20, wherein said dielectric binding layer is selected form the group consisting of Poly-imides (PI), Benzocyclobutene (BCB), Prefluorocyclobutane (PFCB), and the combinations thereof.

22. The light-emitting apparatus according to claim 20, wherein said metal binding layer is selected form the group consisting of In, Sn, AuSn, and the combinations thereof.

23. The light-emitting apparatus according to claim 19, further comprising a third transparent conductive oxide layer formed between said light-emitting stacked layer and said binding layer.

24. The light-emitting apparatus according to claim 23, wherein said third transparent conductive oxide layer is selected form the group consisting of indium tin oxide (ITO), cadmium tin oxide (CTO), antimony tin oxide, zinc indium oxide, aluminum zinc oxide, zinc antimony oxide, and combinations thereof.

25. The light-emitting apparatus according to claim 2, wherein said first plurality of cavities and said second plurality of cavities are shaped into cones or pyramids.

26. The light-emitting apparatus according to claim 14, wherein said third plurality of cavities and said fourth plurality of cavities are shaped into cones or pyramids.

27. The light-emitting apparatus according to claim 12, wherein the area of said first reflective metal layer is substantially the same as the area of said first electrode.