Diode having vertical structure and method of manufacturing the same

• US 7,821,021 B2
• Filed: 11/07/2006
• Issued: 10/26/2010
• Est. Priority Date: 10/26/2001
• Status: Expired due to Fees

• Current Assignee: Suzhou Lekin Semiconductor Company Limited
• Original Assignee: LG Electronics, Inc. (LG Corporation)
• Inventors: Yoo, Myung Cheol
• Primary Examiner(s): TRAN, MINH LOAN
• Application Number:
  US11/593,470
• Publication Number:
  US 20070057273A1
• Time in Patent Office: 1,449 Days
• Field of Search: 257/98, 257/99, 257/103, 257/E33.064, 257/E33.068
• US Class Current: 257/98
• CPC Class Codes: H01L 33/0075 comprising nitride compounds
• CPC Class Codes: H01L 33/0093 Wafer bonding; Removal of the growth substrate
• CPC Class Codes: H01L 33/06 within the light emitting region, e.g. quantum confinement structure or tunnel barrier
• CPC Class Codes: H01L 33/10 with a light reflecting structure, e.g. semiconductor Bragg reflector
• CPC Class Codes: H01L 33/12 with a stress relaxation structure, e.g. buffer layer
• CPC Class Codes: H01L 33/32 containing nitrogen
• CPC Class Codes: H01L 33/325 characterised by the doping materials
• CPC Class Codes: H01L 33/405 Reflective materials
• CPC Class Codes: H01L 33/42 Transparent materials
• CPC Class Codes: H01L 33/46 Reflective coating, e.g. dielectric Bragg reflector
• 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
• CPC Class Codes: H01S 5/3013 AIIIBV compounds

Abstract

A light emitting diode includes a conductive layer, an n-GaN layer on the conductive layer, an active layer on the n-GaN layer, a p-GaN layer on the active layer, and a p-electrode on the p-GaN layer. The conductive layer is an n-electrode.

Claims

1. A vertical light emitting device, comprising:

a GaN layer having a multilayer structure including an n-type layer, an active layer, and a p-type layer, the GaN layer having a first surface and a second surface;

a conductive structure on the first surface of the GaN layer, wherein the conductive structure comprises a first electrode, wherein the first electrode is in contact with the first surface of the GaN layer, wherein the first electrode and the second surface of the GaN layer are configured such that the first electrode reflects light from the active layer back through the second surface of the GaN layer; and

a second electrode in contact with the second surface of the GaN layer,

wherein the conductive structure is located at the bottom of the light emitting device.

2. The vertical light emitting device according to claim 1, wherein the first electrode includes at least one material selected from a group including Al, Ti/Al, Cr/Au, and Ti/Au.

3. The vertical light emitting device according to claim 1, further comprising a transparent contact on the GaN layer.

4. The vertical light emitting device according to claim 3, the transparent contact includes a transparent conductive oxide (TCO).

5. The vertical light emitting device according to claim 3, wherein the transparent contact includes indium-tin-oxide.

6. The vertical light emitting device according to claim 1, wherein the second electrode includes at least one material selected from a group including Ni/Au, Pd/Au, Pd/Ni and Pt.

7. The vertical light emitting device according to claim 1, wherein the active layer includes AlInGaN.

8. The vertical light emitting device according to claim 1, wherein the active layer includes at least one of a quantum well layer and a double hetero structure.

9. The vertical light emitting device according to claim 8, wherein the quantum well layer includes a multiple quantum well layer.

10. The vertical light emitting device according to claim 1, wherein the conductive structure has substantially the same surface area as the first surface of the GaN layer.

11. A vertical light emitting device, comprising:

a first GaN layer of a first conductivity;

an active layer on the first GaN layer;

a second GaN layer of a second conductivity on the active layer;

a first electrode directly on the first GaN layer, wherein the first electrode reflects light from the active layer;

a second electrode contacting a surface of the second GaN layer; and

a pad over the second electrode,

wherein the first electrode is configured to reflect light from the active layer back through the surface of the second GaN layer.

12. The vertical light emitting device according to claim 11, wherein the first electrode includes at least one material selected from a group including Al, Ti/Al, Cr/Au, and Ti/Au.

13. The vertical light emitting device according to claim 11, wherein the first electrode includes Al having a concentration of about 99.999% or higher.

14. The vertical light emitting device according to claim 11, wherein the first electrode includes Al of about 3000 Å

.

15. The vertical light emitting device according to claim 11, further comprising a transparent contact on the second GaN layer.

16. The vertical light emitting device according to claim 15, the transparent contact includes a transparent conductive oxide (TCO).

17. The vertical light emitting device according to claim 15, wherein the transparent contact includes indium-tin-oxide.

18. The vertical light emitting device according to claim 11, wherein the second electrode includes at least one material selected from a group including Ni/Au, Pd/Au, Pd/Ni and Pt.

19. The vertical light emitting device according to claim 11, wherein the active layer includes AlInGaN.

20. The vertical light emitting device according to claim 11, wherein the active layer includes includes at least one of a quantum well layer and a double hetero structure.

21. The vertical light emitting device according to claim 20, wherein the quantum well layer includes a multiple quantum well layer.

22. The vertical light emitting device according to claim 11, further comprising a cladding layer between the first GaN layer and the active layer or between the second GaN layer and the active layer.

23. The vertical light emitting device according to claim 22, wherein the cladding layer includes at least one material selected from a group including n-AlGaN and p-AlGaN.

24. The vertical light emitting device according to claim 11, wherein the first electrode has substantially the same surface area as a surface of the first GaN layer.

25. The vertical light emitting device according to claim 11, wherein the first conductivity is n-type and the second conductivity is p-type.

26. The vertical light emitting device according to claim 11, wherein the first GaN layer comprises a buffer layer.

28. The vertical light emitting device according to claim 11, wherein the first conductivity is p-type and the second conductivity is n-type.

27. A diode, comprising:

a conductive structure;

an n-GaN layer on the conductive structure;

an active layer on the n-GaN layer;

a p-GaN layer on the active layer; and

a p-electrode contacting a surface of the p-GaN layer;

wherein the conductive structure comprises an n-electrode, wherein the n-electrode is configured to reflect light from the active layer back through the surface of the p-GaN layer, and wherein the conductive structure is located at the bottom of the diode.