Method for manufacturing light-emitting element on non-transparent substrate

• US 6,762,069 B2
• Filed: 11/19/2002
• Issued: 07/13/2004
• Est. Priority Date: 11/19/2002
• Status: Active Grant

• Current Assignee: Epistar Corporation
• Original Assignee: United Epitaxy Company (Epistar Corporation)
• Inventors: Chang, Chih-Sung, Yang, Kuang-Neng, Huang, Chung-Kuei, Chen, Tzer-Perng
• Primary Examiner(s): TSAI, H JEY
• Application Number:
  US10/298,567
• Publication Number:
  US 20040096998A1
• Time in Patent Office: 602 Days
• Field of Search: 438/22-24, 438/34-47, 438/455, 438/602-609
• US Class Current: 438/22
• CPC Class Codes: H01L 2933/0016 relating to electrodes
• CPC Class Codes: H01L 33/0093 Wafer bonding; Removal of the growth substrate
• CPC Class Codes: H01L 33/387 with a plurality of electrode regions in direct contact with the semiconductor body and being electrically interconnected by another electrode layer
• CPC Class Codes: H01L 33/405 Reflective materials

Abstract

A method for manufacturing light-emitting device on non-transparent substrate includes the steps of forming a semiconductor epitaxial layer, a first conductive layer, a reflecting layer and a first conduction layer on a first substrate, and forming second conduction layer on a second substrate. Afterward, the first conduction layer and the second conduction layer is bounded by thermal pressing. The first substrate is then removed and a second conductive layer is formed to complete a light-emitting device. The light-emitting device can be incorporated with wetting layer and blocking layer to prevent inner diffusion and enhance external quantum efficiency.

Claims

1. A method for manufacturing light-emitting device on non-transparent substrate, comprising following steps:

a. preparing a first substrate;

b. forming a semiconductor epitaxial layer on the first substrate and functioned as a light emitting layer;

c. forming a first conductive layer on part of an exposed face of the semiconductor epitaxial layer;

d. forming a reflecting layer over the exposed face of the semiconductor epitaxial layer and covering the first conductive layer, the reflecting layer reflecting a light emitted from the semiconductor epitaxial layer;

e. forming a first conduction layer over the reflecting layer;

f. preparing a second substrate;

g. forming a second conduction layer over the second substrate;

h. bonding the first conduction layer and the second conduction layer by thermal pressing;

i. removing the first substrate;

j. forming a second conductive layer on a second face of the semiconductor epitaxial layer opposite to the first face.

2. The method for manufacturing light-emitting device on non-transparent substrate as in claim 1, wherein the semiconductor epitaxial layer is GaN based material.

3. The method for manufacturing light-emitting device on non-transparent substrate as in claim 1, wherein the first substrate is selected from a group consisting of sapphire, Si, GaAs and GaP.

4. The method for manufacturing light-emitting device on non-transparent substrate as in claim 1, wherein the first conductive layer has an area less than an area of the semiconductor epitaxial layer and has pattern in one of dot and mesh fashion.

5. The method for manufacturing light-emitting device on non-transparent substrate as in claim 1, wherein the reflecting layer is selected from a group consisting of Au, Ag and Al.

6. The method for manufacturing light-emitting device on non-transparent substrate as in claim 1, wherein the first conduction layer has a melting point between 160°

C. and 400°

C.

7. The method for manufacturing light-emitting device on non-transparent substrate as in claim 1, wherein the first conduction layer is selected from a group consisting of In and AuSn.

8. The method for manufacturing light-emitting device on non-transparent substrate as in claim 1, wherein the second substrate is selected from a group consisting of Si, SiC, graphite, Al and Cu.

9. The method for manufacturing light-emitting device on non-transparent substrate as in claim 1, wherein the second conduction layer is Au.

10. The method for manufacturing light-emitting device on non-transparent substrate as in claim 1, wherein the step (h) is performed at temperature between 160°

C. and 400°

C.

11. The method for manufacturing light-emitting device on non-transparent substrate as in claim 1, wherein the step (h) is performed by at least one of wet- and dry-chemical etching to expose the semiconductor epitaxial layer.

12. The method for manufacturing light-emitting device on non-transparent substrate as in claim 1, wherein the second conductive layer has an area less than an area of the semiconductor epitaxial layer and larger than a wiring pad.

13. The method for manufacturing light-emitting device on non-transparent substrate as in claim 1, wherein the first conductive layer is selected from a group consisting of Ni/Au, Pt/Au and Pd/Au.

14. The method for manufacturing light-emitting device on non-transparent substrate as in claim 1, wherein the semiconductor epitaxial layer is selected from a group consisting of AlGaAs and AlGaInP.

15. The method for manufacturing light-emitting device on non-transparent substrate as in claim 1, wherein the first substrate is selected from a group consisting of Si, Sic and Ge.

16. A method for manufacturing light-emitting device on non-transparent substrate, comprising following steps:

a. preparing a first substrate;

b. forming an epitaxial layer of first conductive type on the first substrate;

c. forming an active epitaxial layer on the epitaxial layer of first conductive type;

d. forming an epitaxial layer of second conductive type on the active epitaxial layer;

e. forming a first conductive layer on the epitaxial layer of second conductive type;

f. forming a reflecting layer over the first conductive layer, the reflecting layer reflecting a light emitted from the active epitaxial layer;

g. forming a first conduction layer over the reflecting layer;

h. preparing a second substrate;

i. forming a wetting layer on the second substrate;

j. forming a blocking layer on the wetting layer;

k. forming a second conduction layer over the blocking layer;

l. bonding the first conduction layer and the second conduction layer by thermal pressing;

m. removing the first substrate;

n. forming a second conductive layer on the epitaxial layer of first conductive type.

17. The method for manufacturing light-emitting device on non-transparent substrate as in claim 16, wherein the semiconductor epitaxial layer is GaN based material.

18. The method for manufacturing light-emitting device on non-transparent substrate as in claim 16, wherein the first substrate is selected from a group consisting of Si, GaAs and GaP.

19. The method for manufacturing light-emitting device on non-transparent substrate as in claim 16, wherein the first conductive type is N type and the second conductive type is P type.

20. The method for manufacturing light-emitting device on non-transparent substrate as in claim 16, wherein the first conductive layer has an area less than an area of the semiconductor epitaxial layer and has pattern in one of dot and mesh fashion.

21. The method for manufacturing light-emitting device on non-transparent substrate as in claim 16, wherein the reflecting layer is selected from a group consisting of Au, Ag and Al.

22. The method for manufacturing light-emitting device on non-transparent substrate as in claim 16, wherein the first conduction layer has a melting point between 160°

C. and 400°

C.

23. The method for manufacturing light-emitting device on non-transparent substrate as in claim 16, wherein the first conduction layer is selected from a group consisting of In and AuSn.

24. The method for manufacturing light-emitting device on non-transparent substrate as in claim 16, wherein the second substrate is selected from a group consisting of Si, SiC, graphite, Al and Cu.

25. The method for manufacturing light-emitting device on non-transparent substrate as in claim 16, wherein the wetting layer is selected from a group consisting of Ti and Cr.

26. The method for manufacturing light-emitting device on non-transparent substrate as in claim 16, wherein the blocking layer is selected from a group consisting of Pt and Mo.

27. The method for manufacturing light-emitting device on non-transparent substrate as in claim 16, wherein the second conduction layer is Au.

28. The method for manufacturing light-emitting device on non-transparent substrate as in claim 16, wherein the step (l) is performed at temperature between 160°

C. and 400°

C.

29. The method for manufacturing light-emitting device on non-transparent substrate as in claim 16, wherein the step (m) is performed by at least one of wet- and dry-chemical etching to expose the semiconductor epitaxial layer.

30. The method for manufacturing light-emitting device on non-transparent substrate as in claim 16, wherein the second conductive layer has an area less than an area of the semiconductor epitaxial layer and larger than a wiring pad.

31. The method for manufacturing light-emitting device on non-transparent substrate as in claim 16, wherein the second conductive layer is selected from a group consisting of Ti/Al and Ti/Au.

32. The method for manufacturing light-emitting device on non-transparent substrate as in claim 16, wherein the first conductive layer is selected from a group consisting of Ni/Au, Pt/Au and Pd/Au.

33. The method for manufacturing light-emitting device on non-transparent substrate as in claim 17, wherein the semiconductor epitaxial layer is selected from a group consisting of AlGaAs and AlGaInP.

34. The method for manufacturing light-emitting device on non-transparent substrate as in claim 18, wherein the first substrate is selected from a group consisting of Si and Ge.

35. The method for manufacturing light-emitting device on non-transparent substrate as in claim 31, wherein the second conductive layer is selected from a group consisting of AuGe/Ni/Au and AuGe/Au.

36. The method for manufacturing light-emitting device on non-transparent substrate as in claim 32, wherein the first conductive layer is selected from a group consisting of Ti/Pt//Au, AuBe/Au amd AuZn/Au.