Fabrication method of gallium nitride-based compound semiconductor

• US 20110003420A1
• Filed: 12/04/2009
• Published: 01/06/2011
• Est. Priority Date: 07/02/2009
• Status: Abandoned Application

• Current Assignee: Sino-American Silicon Products Incorporated
• Original Assignee: Sino-American Silicon Products Incorporated
• Inventors: Yu, Sheng-Fu, Chen, Miin-Jang, Ho, Szu-Hua, Lin, Ray-Ming, Hsu, Wen-Ching
• Application Number:
  US12/592,926
• Publication Number:
  US 20110003420A1
• Time in Patent Office: Days
• US Class Current: 438/47
• CPC Class Codes: H01L 21/0237 Materials
• CPC Class Codes: H01L 21/02403 Oxides
• CPC Class Codes: H01L 21/0242 Crystalline insulating materials
• CPC Class Codes: H01L 21/0243 Surface structure
• CPC Class Codes: H01L 21/02458 Nitrides
• CPC Class Codes: H01L 21/02472 Oxides
• CPC Class Codes: H01L 21/02507 Alternating layers, e.g. superlattice
• CPC Class Codes: H01L 21/0254 Nitrides
• CPC Class Codes: H01L 21/0262 Reduction or decomposition of gaseous compounds, e.g. CVD
• CPC Class Codes: H01L 33/007 comprising nitride compounds
• CPC Class Codes: H01L 33/12 with a stress relaxation structure, e.g. buffer layer

Abstract

The present invention discloses a method for fabricating gallium nitride(GaN)-based compound semiconductors. Particularly, this invention relates to a method of forming a transition layer on a zinc oxide (ZnO)-based semiconductor layer by the steps of forming a wetting layer and making the wetting layer nitridation. The method not only provides a function of protecting the ZnO-based semiconductor layer, but also uses the transition layer as a buffer layer for a following epitaxial growth of a GaN-based semiconductor layer, and thus, the invention may improve the crystal quality of the GaN-based semiconductor layer effectively.

Claims

1. A fabrication method of gallium nitride (GaN)-based compound semiconductors, comprising the steps of:

providing a zinc oxide (ZnO)-based semiconductor layer;

forming a wetting layer on the ZnO-based semiconductor layer;

nitrifying the wetting layer;

repeating the steps of forming the wetting layer and nitrifying the wetting layer many times to form a transition layer; and

forming a GaN-based semiconductor layer on the transition layer.

2. The fabrication method of claim 1, wherein the wetting layer is formed by using a reaction precursor selected from the group consisting of trimethylaluminum, trimethylgallium, trimethylindium, triethylaluminum, triethylgallium and triethylalindium.

3. The fabrication method of claim 1, wherein the wetting layer is nitrified by using a reaction precursor selected from the group consisting of ammonia gas, dimethylhydrazine and tert-butylhydrazine.

4. The fabrication method of claim 1, wherein the transition layer is formed at a temperature not greater than 900°

C.

5. The fabrication method of claim 1, wherein the GaN-based semiconductor layer is formed at a temperature between 850˜

1050°

C.

6. The fabrication method of claim 1, wherein the ZnO-based semiconductor layer is formed on a different bulk substrate.

7. The fabrication method claim 6, wherein the different bulk substrate includes sapphire, silicon carbide, magnesium oxide, gallium oxide, lithium gallium oxide, lithium aluminum oxide, spinel, silicon, germanium, gallium arsenide, gallium phosphide, glass or zirconium diboride.

8. The fabrication method claim 6, wherein the bulk substrate further includes a patterned surface.

9. The fabrication method of claim 1, wherein the ZnO-based semiconductor layer is a single crystal ZnO bulk substrate.

10. The fabrication method of claim 1, wherein the step of forming the transition layer further comprises forming the wetting layer on the ZnO-based semiconductor layer at a first temperature, and nitrifying the wetting layer at a second temperature.

11. The fabrication method of claim 10, wherein the second temperature is not less than the first temperature.

12. The fabrication method of claim 1, wherein the ZnO-based semiconductor layer further includes a patterned surface.

13. A fabrication method of gallium nitride (GaN)-based compound semiconductors, comprising the steps of:

providing a zinc oxide (ZnO)-based semiconductor layer;

forming a first transition layer on the ZnO-based semiconductor layer;

forming a second transition layer on the first transition layer; and

forming a GaN-based semiconductor layer on the second transition layer.

14. The fabrication method of claim 13, wherein the step of forming the first transition layer further comprises repeatly forming a first wetting layer and nitrifying the first wetting layer for many times.

15. The fabrication method of claim 13, wherein the steps of forming the second transition layer further comprises repeatly forming a second wetting layer and nitrifying the second wetting layer for many times.

16. The fabrication method of claim 13, wherein the second transition layer is formed at a temperature not less than a temperature of forming the first transition layer.

17. The fabrication method of claim 14, wherein the first wetting layer is formed by using a trimethylaluminum, trimethylgallium, trimethylindium, triethylaluminum, triethylgallium or triethylalindium reaction precursor.

18. The fabrication method of claim 15, wherein the second wetting layer is formed by using a trimethylaluminum, trimethylgallium, trimethylindium, triethylaluminum, triethylgallium or triethylalindium reaction precursor.

19. The fabrication method of claim 13, wherein wetting layers are nitrided by using an ammonia gas, dimethylhydrazine or tert-butylhydrazine reaction precursor and formed on the first transition layer and the second transition layer.

20. The fabrication method of claim 13, wherein the ZnO-based semiconductor layer further includes a patterned surface.

21. The fabrication method of claim 13, wherein the ZnO-based semiconductor layer is formed on a patterned bulk substrate.

22. A fabrication method of gallium nitride (GaN)-based compound semiconductors, comprising the step of:

providing a sapphire substrate;

forming a zinc oxide (ZnO)-based semiconductor layer on the sapphire substrate;

forming a transition layer on the ZnO-based semiconductor layer;

forming a non-doped GaN-based semiconductor layer on the transition layer;

forming a N-type doped GaN-based ohm contact layer on the non-doped GaN-based semiconductor layer;

forming a light emitting layer of an InGN multiple quantum well structure on the N-type doped GaN-based ohm contact layer;

forming a P-type doped AlGaN cladding layer on the light emitting layer of the InGN multiple quantum well structure; and

forming a P-type doped GaN-based ohm contact layer on the P-type doped AlGaN cladding layer.

23. The fabrication method of claim 22, wherein the step of forming the transition layer further comprises the step of forming a wetting layer on the ZnO-based semiconductor layer by using a reaction precursor selected from the group consisting of trimethylaluminum, trimethylgallium, trimethylindium, triethylaluminum, triethylgallium and triethylalindium.

24. The fabrication method of claim 23, wherein the step of forming the transition layer on the wetting layer further comprises the step of nitrifying the wetting layer by using a reaction precursor selected from the group consisting of ammonia gas, dimethylhydrazine and tert-butylhydrazine.