Single crystal rhombohedral epitaxy of SiGe on sapphire at 450° C.-500° C. substrate temperatures

Patent metadata

Field	Value
Publication number	US-10096472-B2
Application number	US-201615386592-A
Country	US
Kind code	B2
Filing date	Dec 21, 2016
Priority date	Dec 21, 2015
Publication date	Oct 9, 2018
Grant date	Oct 9, 2018

Abstract

Various embodiments may provide a low temperature (i.e., less than 850° C.) method of Silicon-Germanium (SiGe) on sapphire (Al 2 O 3 ) (SiGe/sapphire) growth that may produce a single crystal film with less thermal loading effort to the substrate than conventional high temperature (i.e., temperatures above 850° C.) methods. The various embodiments may alleviate the thermal loading requirement of the substrate, which in conventional high temperature (i.e., temperatures above 850° C.) methods had surface temperatures within the range of 850° C.-900° C. The various embodiments may provide a new thermal loading requirement of the sapphire substrate for growing single crystal SiGe on the sapphire substrate in the range of about 450° C. to about 500° C.

First claim

What is claimed is:

1. A method of growing a Silicon-Germanium (SiGe) layer on a sapphire (Al 2 O 3 ) wafer, comprising:
providing a sapphire wafer;
heating the sapphire wafer to a wafer surface temperature at or below about 500° C.;
growing mono-crystalline SiGe on the sapphire wafer at the wafer surface temperature thereby forming a SiGe/sapphire wafer including a SiGe layer and an Al 2 O 3 substrate; and
cooling the SiGe/sapphire wafer.

2. The method of claim 1 , wherein heating, growing, and cooling is completed in less than one hour.

3. The method of claim 2 , wherein the growing occurs immediately after the heating without a thermal soak step.

4. The method of claim 3 , wherein a separate silicon (Si) layer is not deposited on the sapphire wafer prior to the growing.

5. The method of claim 4 , wherein the wafer surface temperature is about 500° C.

6. The method of claim 4 , wherein the wafer surface temperature is about 450° C.

7. The method of claim 4 , wherein the wafer surface temperature is about 450° C. to about 500° C.

8. The method of claim 1 , wherein the wafer surface temperature is about 500° C.

9. The method of claim 1 , wherein the wafer surface temperature is about 450° C.

10. The method of claim 1 , wherein the wafer surface temperature is about 450° C. to about 500° C.

11. A semiconductor device, comprising:
a Silicon-Germanium (SiGe)

layer and a sapphire (Al 2 O 3 ) layer substrate, wherein the layers are formed by:
providing a sapphire wafer;
heating the sapphire wafer to a wafer surface temperature at or below about 500° C.;
growing mono-crystalline SiGe on the sapphire wafer at the wafer surface temperature thereby forming a SiGe/sapphire wafer including a SiGe layer and an Al 2 O 2 substrate; and
cooling the SiGe/sapphire wafer.

12. The semiconductor device of claim 11 , wherein heating, growing, and cooling is completed in less than one hour.

13. The semiconductor device of claim 12 , wherein the growing occurs immediately after the heating without a thermal soak step.

14. The semiconductor device of claim 13 , wherein a separate silicon (Si) layer is not deposited on the sapphire wafer prior to the growing.

15. The semiconductor device of claim 11 , wherein the wafer surface temperature is about 500° C.

16. The semiconductor device of claim 11 , wherein the wafer surface temperature is about 450° C.

17. The method of claim 11 , wherein the wafer surface temperature is about 450° C. to about 500° C.

18. The method of claim 14 , wherein the wafer surface temperature is about 500° C.

19. The method of claim 14 , wherein the wafer surface temperature is about 450° C.

20. The method of claim 14 , wherein the wafer surface temperature is about 450° C. to about 500° C.

Assignees

• Nasa
• Nasa

Inventors

• Choi Sang Hyouk
• Duzik Adam J

Classifications

• H10P14/3466

  Crystal orientation · CPC title

• H10P14/3458

  Monocrystalline · CPC title

• H10P14/2926

  Crystal orientations · CPC title

• H10P14/2921

  being crystalline insulating materials · CPC title

• H10P14/20

  of semiconductor materials · CPC title