Light-emitting diode and method for manufacturing the same

• US 20080191233A1
• Filed: 12/07/2007
• Published: 08/14/2008
• Est. Priority Date: 02/13/2007
• Status: Abandoned Application

• Current Assignee: Epistar Corporation (Ennostar, Inc.)
• Original Assignee: Epistar Corporation (Ennostar, Inc.)
• Inventors: Kuo, Cheng-Ta, Yang, Yu-Cheng, Jou, Li-Ping, Huang, Sen-Pin
• Application Number:
  US12/000,040
• Publication Number:
  US 20080191233A1
• Time in Patent Office: Days
• US Class Current: 257/98
• CPC Class Codes: H01L 33/0093 Wafer bonding; Removal of the growth substrate
• CPC Class Codes: H01L 33/405 Reflective materials

Abstract

A light-emitting diode and method for manufacturing the same are described. The light-emitting diode comprises: a conductive substrate including a first surface and a second surface on opposite sides; a reflector structure comprising a conductive reflector layer bonding to the first surface of the conductive substrate and a conductive distributed Bragg reflector (DBR) structure stacked on the conductive reflector layer; an illuminant epitaxial structure disposed on the reflector structure; a first electrode disposed on a portion of the illuminant epitaxial structure; and a second electrode bonded to the second surface of the conductive substrate.

Claims

1. A light-emitting diode, comprising:

a conductive substrate including a first surface and a second surface on opposite sides;

a reflector structure comprising;

a conductive reflector layer formed on the first surface of the conductive substrate; and

a conductive distributed Bragg reflector structure formed on the conductive reflector layer;

an illuminant epitaxial structure disposed on the reflector structure;

a first electrode disposed on a portion of the illuminant epitaxial structure; and

a second electrode formed on the second surface of the conductive substrate.

2. The light-emitting diode according to claim 1, wherein the conductive reflector layer is a metal reflector layer.

3. The light-emitting diode according to claim 1, wherein a material of the conductive reflector layer is selected from the group consisting of Al, Au, Pt, Zn, Ag, Ni, Ge, In, Sn, and alloys thereof.

4. The light-emitting diode according to claim 1, further comprising a conductive bonding layer located between the conductive substrate and the conductive reflector layer.

5. The light-emitting diode according to claim 1, wherein the conductive distributed Bragg reflector structure comprises:

a first low refractive index transparent conductive layer disposed on the conductive reflector layer;

a high refractive index transparent conductive layer stacked on the first low refractive index transparent conductive layer; and

a second low refractive index transparent conductive layer stacked on the high refractive index transparent conductive layer.

6. The light-emitting diode according to claim 1, wherein the conductive distributed Bragg reflector structure is a multi-layer stacked structure, and the multi-layer stacked structure comprises a plurality of low refractive index transparent conductive layers and a plurality of high refractive index transparent conductive layers stacked alternately.

7. The light-emitting diode according to claim 1, wherein a material of the conductive distributed Bragg reflector structure is selected from the group consisting of ITO, CTO, ZnO, In₂O₃, SnO₂, CuAlO₂, CuGaO₂,and SrCu₂O₂.

8. A light-emitting diode, comprising:

a transparent substrate;

an illuminant epitaxial structure comprising;

a first conductivity type semiconductor layer disposed on the transparent substrate;

an active layer disposed on a first portion of the first conductivity type semiconductor layer and exposing a second portion of the first conductivity type semiconductor layer; and

a second conductivity type semiconductor layer disposed on the active layer, wherein the first conductivity type semiconductor layer and the second conductivity type semiconductor layer are different conductivity types;

a reflector structure comprising;

a conductive distributed Bragg reflector structure formed on the second conductivity type semiconductor layer; and

a conductive reflector layer formed on the conductive distributed Bragg reflector structure;

a first conductivity type electrode disposed the second portion of the first conductivity type semiconductor layer; and

a second conductivity type electrode disposed on the reflector structure.

9. The light-emitting diode according to claim 8, wherein the conductive reflector layer is a metal reflector layer.

10. The light-emitting diode according to claim 8, wherein the conductive distributed Bragg reflector structure comprises:

a first low refractive index transparent conductive layer disposed on the second conductivity type semiconductor layer;

a high refractive index transparent conductive layer stacked on the first low refractive index transparent conductive layer; and

a second low refractive index transparent conductive layer stacked on the high refractive index transparent conductive layer.

11. The light-emitting diode according to claim 8, wherein the conductive distributed Bragg reflector structure is a multi-layer stacked structure, and the multi-layer stacked structure comprises a plurality of low refractive index transparent conductive layers and a plurality of high refractive index transparent conductive layers stacked alternately.

12. The light-emitting diode according to claim 8, wherein a material of the conductive distributed Bragg reflector structure is selected from the group consisting of ITO, CTO, ZnO, In₂O₃, SnO₂, CuAlO₂, CuGaO₂, and SrCu₂O₂.

13. A light-emitting diode, comprising:

a substrate including a first surface and a second surface on opposite sides;

a reflector structure comprising;

a conductive reflector layer formed on the first surface of the conductive substrate; and

a conductive distributed Bragg reflector structure formed on the conductive reflector layer; and

an illuminant epitaxial structure disposed on the reflector structure.

14. The light-emitting diode according to claim 13, wherein the conductive distributed Bragg reflector structure comprises:

a first low refractive index transparent conductive layer disposed on the conductive reflector layer;

a high refractive index transparent conductive layer stacked on the first low refractive index transparent conductive layer; and

a second low refractive index transparent conductive layer stacked on the high refractive index transparent conductive layer.

15. The light-emitting diode according to claim 13, wherein the conductive distributed Bragg reflector structure is a multi-layer stacked structure, and the multi-layer stacked structure comprises a plurality of low refractive index transparent conductive layers and a plurality of high refractive index transparent conductive layers stacked alternately.

16. The light-emitting diode according to claim 13, wherein the substrate is a conductive substrate.

17. The light-emitting diode according to claim 16, further comprising a first electrode disposed on a portion of the illuminant epitaxial structure and a second electrode bonded to the second surface of the substrate.

18. The light-emitting diode according to claim 16, further comprising a conductive bonding layer located between the substrate and the conductive reflector layer.

19. The light-emitting diode according to claim 13, wherein the substrate is a transparent substrate.

20. The light-emitting diode according to claim 19, wherein the illuminant epitaxial structure comprising:

a first conductivity type semiconductor layer disposed on the transparent substrate;

an active layer disposed on a first portion of the first conductivity type semiconductor layer and exposing a second portion of the first conductivity type semiconductor layer; and

a second conductivity type semiconductor layer disposed on the active layer, wherein the first conductivity type semiconductor layer and the second conductivity type semiconductor layer are different conductivity types.

21. The light-emitting diode according to claim 20, further comprising a first conductivity type electrode disposed the second portion of the first conductivity type semiconductor layer and a second conductivity type electrode disposed on the reflector structure.

22. A method for manufacturing a light-emitting diode, comprising:

providing a growth substrate;

forming an illuminant epitaxial structure on the growth substrate;

forming a reflector structure on the illuminant epitaxial structure, wherein the reflector structure comprises;

a conductive distributed Bragg reflector structure disposed on the illuminant epitaxial structure; and

a conductive reflector layer disposed on the conductive distributed Bragg reflector structure;

bonding a conductive substrate to the conductive reflector layer, wherein the conductive substrate includes a first surface and a second surface on opposite sides, and the first surface of the conductive substrate is connected to the conductive reflector layer;

removing the growth substrate to expose the illuminant epitaxial structure; and

forming a first electrode and a second electrode respectively on a portion of the illuminant epitaxial structure and the second surface of the conductive substrate.

23. The method for manufacturing a light-emitting diode according to claim 22, wherein the conductive distributed Bragg reflector structure comprises:

a first low refractive index transparent conductive layer disposed on the illuminant epitaxial structure;

a high refractive index transparent conductive layer stacked on the first low refractive index transparent conductive layer; and

a second low refractive index transparent conductive layer stacked on the high refractive index transparent conductive layer.

24. The method for manufacturing a light-emitting diode according to claim 22, wherein the conductive distributed Bragg reflector structure is a multi-layer stacked structure, and the multi-layer stacked structure comprises a plurality of low refractive index transparent conductive layers and a plurality of high refractive index transparent conductive layers stacked alternately.

25. The method for manufacturing a light-emitting diode according to claim 22, wherein the step of bonding the conductive substrate to the conductive reflector layer comprises using a conductive bonding layer.

26. A method for manufacturing a light-emitting diode, comprising:

providing a transparent substrate;

forming an illuminant epitaxial structure on the transparent substrate, wherein the illuminant epitaxial structure comprises a first conductivity type semiconductor layer, an active layer and a second conductivity type semiconductor layer stacked in sequence, wherein the first conductivity type semiconductor layer and the second conductivity type semiconductor layer are different conductivity types;

defining the illuminant epitaxial structure to expose a portion of the first conductivity type semiconductor layer;

forming a reflector structure on the second conductivity type semiconductor layer, wherein the reflector structure comprises;

a conductive distributed Bragg reflector structure disposed on the second conductivity type semiconductor layer; and

a conductive reflector layer stacked on the conductive distributed Bragg reflector structure; and

forming a first conductivity type electrode and a second conductivity type electrode respectively on the exposed portion of the first conductivity type semiconductor layer and the conductive reflector layer.

27. The method for manufacturing a light-emitting diode according to claim 26, wherein the conductive distributed Bragg reflector structure comprises:

a first low refractive index transparent conductive layer disposed on the second conductivity type semiconductor layer;

a high refractive index transparent conductive layer stacked on the first low refractive index transparent conductive layer; and

a second low refractive index transparent conductive layer stacked on the high refractive index transparent conductive layer.

28. The method for manufacturing a light-emitting diode according to claim 26, wherein the conductive distributed Bragg reflector structure is a multi-layer stacked structure, and the multi-layer stacked structure comprises a plurality of low refractive index transparent conductive layers and a plurality of high refractive index transparent conductive layers stacked alternately.