Method for forming a semiconductor device having a metallic substrate

• US 6,468,824 B2
• Filed: 03/22/2001
• Issued: 10/22/2002
• Est. Priority Date: 03/22/2001
• Status: Expired due to Term

• Current Assignee: Unit Light Technology Incorporated
• Original Assignee: Unit Light Technology Incorporated
• Inventors: Chen, Chien-An, Yih, Nae-Guann, Wu, Bor-Jen, Chen, Nai-Chuan, Tzou, Yuan-Hsin
• Primary Examiner(s): Booth, Richard
• Assistant Examiner(s): Roman, Angel
• Application Number:
  US09/814,412
• Publication Number:
  US 20020137243A1
• Time in Patent Office: 579 Days
• Field of Search: 438/29, 438/34, 438/46, 438/47, 438/455, 438/458, 438/459
• US Class Current: 438/46
• CPC Class Codes: H01L 21/6835 using temporarily an auxiliary support
• CPC Class Codes: H01L 2933/0075 relating to heat extraction or cooling elements
• CPC Class Codes: H01L 33/0093 Wafer bonding; Removal of the growth substrate
• CPC Class Codes: H01L 33/641 characterized by the materials

Abstract

The present invention provides a method for forming a semiconductor device with a metallic substrate. The method comprises providing a semiconductor substrate. At least a semiconductor layer is formed on the semiconductor substrate. A metallic electrode layer is formed on the semiconductor layer. The metallic substrate is formed on the metallic electrode layer and the semiconductor substrate is removed. The metallic substrate has advantages of high thermal and electrical conductivity, that can improve the reliability and life-time of the semiconductor device.

Claims

1. A method for forming a semiconductor device with a metallic substrate, said method comprising:

providing a semiconductor substrate;

forming at least a semiconductor layer on said semiconductor substrate;

forming a metallic electrode layer on said semiconductor layer;

forming said metallic substrate on a surface of said metallic electrode layer; and

removing said semiconductor substrate.

2. The method according to claim 1, wherein said metallic electrode layer is formed by electroplating an Au/Be layer and thereafter annealing.

3. The method according to claim 1, wherein said metallic electrode layer is formed by electroplating an Au/Zn layer and thereafter annealing.

4. The method according to claim 1, wherein said metallic substrate is formed by evaporation of metals selected from the groups of Au, Pt, Pd, Zn, Al, Ni, Ti, alloys of the above, or any combination of alloys of the above.

5. The method according to claim 1, wherein said metallic substrate is formed by sputtering of metals selected from the groups of Au, Pt, Pd, Zn, Al, Ni, Ti, alloys of the above, or any combination of alloys of the above.

6. The method according to claim 1, wherein said metallic substrate is formed by melting cold-forming metals that subsequently are cast on said metallically electrode layer, and said cold-forming metals are selected from the groups of In, Pb, Sn, or alloys of the above.

7. The method according to claim 1, wherein said metallic substrate is formed by electroplating that uses said metallic electrode layer as a cathode.

8. The method according to claim 7, wherein said metallic substrate is made of electroplated copper.

9. The method according to claim 7, wherein said metallic substrate is made of electroplated nickel.

10. The method according to claim 1, wherein said semiconductor device comprises an optical semiconductor device.

11. A method for forming an optical semiconductor device, said method comprising:

providing a semiconductor substrate;

forming at least a semiconductor layer on said semiconductor substrate;

forming a metallic electrode layer on said semiconductor layer;

forming a first metallic substrate on a surface of said metallic electrode layer;

removing said semiconductor substrate; and

forming a second metallic substrate on said semiconductor layer.

12. The method according to claim 11, wherein said metallic electrode layer is formed by electroplating an Au/Be layer and thereafter annealing.

13. The method according to claim 11, wherein said first metallic electrode layer is formed by electroplating an Au/Zn layer and thereafter annealing.

14. The method according to claim 11, wherein said metallic substrate is formed by evaporation of metals selected from the groups of Au, Pt, Pd, Zn, Al, Ni, Ti, alloys of the above, or any combination of alloys of the above.

15. The method according to claim 11, wherein said first metallic substrate is formed by sputtering of metals selected from the groups of Au, Pt, Pd, Zn, Al, Ni, Ti, alloys of the above, or any combination of alloys of the above.

16. The method according to claim 11, wherein said first metallic substrate is formed by melting cold-forming metals that subsequently are cast on said metallically electrode layer, and said cold-forming metals are selected from the groups of In, Pb, Sn, or alloys of the above.

17. The method according to claim 11, wherein said first metallic substrate is formed by electroplating that uses said metallic electrode layer as a cathode.

18. The method according to claim 17, wherein said first metallic substrate is made of electroplated copper.

19. The method according to claim 17, wherein said first metallic substrate is made of electroplated nickel.

20. The method according to claim 11 further comprising forming a distributed Bragg reflector between said semiconductor layer and said metallic electrode layer thereby enhances refractive index.

21. The method according to claim 11 further comprising forming a non-absorbing layer between said semiconductor layer and said metallic electrode layer, which has a reflectivity less than that of semiconductor layer.

22. A method for forming a light emitting diode (LED) having a metallic substrate, said method comprising:

providing a semiconductor substrate;

epitaxially growing a lamination of LED layers on said semiconductor substrate;

forming a metallic electrode layer on said lamination of LED layers;

forming a metallic substrate on a surface of said metallic electrode layer; and

removing said semiconductor substrate.

23. The method according to claim 22, wherein said metallic electrode layer is formed by electroplating an Au/Be layer and thereafter annealing.

24. The method according to claim 22, wherein said metallic electrode layer is formed by electroplating an Au/Zn layer and thereafter annealing.

25. The method according to claim 22, wherein said metallic substrate is formed by evaporation of metals selected from the groups of Au, Pt, Pd, Zn, Al, Ni, Ti, alloys of the above, or any combination of alloys of the above.

26. The method according to claim 22, wherein said metallic substrate is formed by sputtering of metals selected from the groups of Au, Pt, Pd, Zn, Al, Ni, Ti, alloys of the above, or any combination of alloys of the above.

27. The method according to claim 22, wherein said metallic substrate is formed by melting cold-forming metals that subsequently are cast on said metallically electrode layer, and said cold-forming metals are selected from the groups of In, Pb, Sn, or alloys of the above.

28. The method according to claim 22, wherein said metallic substrate is formed by electroplating that uses said metallic electrode layer as a cathode.