Method for enhancing growth of semipolar (Al,In,Ga,B)N via metalorganic chemical vapor deposition

• US 7,687,293 B2
• Filed: 01/19/2007
• Issued: 03/30/2010
• Est. Priority Date: 01/20/2006
• Status: Active Grant

• Current Assignee: Regents of the University of California (University of California)
• Original Assignee: Regents of the University of California (University of California)
• Inventors: Sato, Hiroshi, Kaeding, John F., Baker, Troy J., DenBaars, Steven P., Haskell, Benjamin A., Nakamura, Shuji, Iza, Michael
• Primary Examiner(s): Ghyka; Alexander G
• Assistant Examiner(s): Chang; Leonard
• Application Number:
  US11/655,572
• Publication Number:
  US 20070218655A1
• Time in Patent Office: 1,166 Days
• Field of Search: 438932-933, 438/22, 438/36, 438/41, 438/44, 438/46, 438/48, 438/481, 438/485, 257/12, 257/13, 257/79, 257/86, 257/94, 257/103, 257/E21.113, 257/E21.121, 257/E21.463
• US Class Current: 438/46
• CPC Class Codes: C30B 25/02 Epitaxial-layer growth
• CPC Class Codes: C30B 29/403 AIII-nitrides
• CPC Class Codes: C30B 29/406 Gallium nitride
• CPC Class Codes: H01L 21/02365 Forming inorganic semiconducting materials on a substrate for light-sensitive devices H01L31/00
• CPC Class Codes: H01L 21/0242 Crystalline insulating materials
• CPC Class Codes: H01L 21/02433 Crystal orientation
• CPC Class Codes: H01L 21/02458 Nitrides
• CPC Class Codes: H01L 21/02502 consisting of two layers
• CPC Class Codes: H01L 21/02516 Crystal orientation
• 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 29/045 by their particular orientation of crystalline planes

Abstract

A method for enhancing growth of device-quality planar semipolar nitride semiconductor thin films via metalorganic chemical vapor deposition (MOCVD) by using an (Al,In,Ga)N nucleation layer containing at least some indium. Specifically, the method comprises loading a substrate into a reactor, heating the substrate under a flow of nitrogen and/or hydrogen and/or ammonia, depositing an In_xGa_1-xN nucleation layer on the heated substrate, depositing a semipolar nitride semiconductor thin film on the In_xGa_1-xN nucleation layer, and cooling the substrate under a nitrogen overpressure.

Claims

1. A method for enhancing growth of a device-quality planar semipolar nitride semiconductor film comprising:

(a) depositing a semipolar nitride semiconductor film on an (Al,In,Ga)N nucleation or buffer layer comprising at least some indium, wherein an area of the semipolar nitride semiconductor film is substantially parallel to a substrate surface upon which the (Al,In,Ga)N nucleation or buffer layer is grown.

2. The method of claim 1, wherein the (Al,In,Ga)N nucleation or buffer layer comprises an In_xGa_1-xN nucleation layer with x>

0.

3. The method of claim 1, wherein the (Al,In,Ga)N nucleation or buffer layer comprises an In_xGa_1-xN nucleation layer with x=0.1.

4. The method of claim 1, wherein the semipolar nitride semiconductor film comprises an alloy composition of (Ga,Al,In,B)N semiconductors having a formula Ga_nAl_xIn_yB_zN where 0≦

n≦

1, 0≦

x≦

1, 0≦

y≦

1, 0≦

z≦

1 and n+x+y+z=1.

5. The method of claim 1, wherein the area is greater than 10 microns wide.

6. The method of claim 1, wherein the (Al,In,Ga)N nucleation or buffer layer is grown on a (10 10) sapphire substrate.

7. The method of claim 1, wherein the semipolar nitride semiconductor film comprises a {11 22}semipolar nitride semiconductor film grown on the (Al,In,Ga)N nucleation or buffer layer.

8. The method of claim 1, wherein the (Al,In,Ga)N nucleation or buffer layer is grown on an {11 22} GaN template grown on a (10 10) sapphire substrate.

9. The method of claim 1, wherein the semipolar nitride semiconductor film is grown via metalorganic chemical vapor deposition (MOCVD).

10. The method of claim 1, wherein the semipolar nitride semiconductor film has a surface morphology needed for nitride semipolar electronic devices, comprising a planar film surface, fewer surface undulations, and a reduced number of crystallographic defects as compared to deposition without the (Al,In,Ga)N nucleation or buffer layer.

11. A device fabricated using the method of claim 1.

12. A method for growing device-quality planar semipolar nitride semiconductor films, comprising:

(a) loading a substrate into a reactor;

(b) heating the substrate under a flow comprising at least one of nitrogen, hydrogen and ammonia;

(c) depositing an In_xGa_1-xN nucleation layer on the heated substrate;

(d) depositing a semipolar nitride semiconductor film on the In_xGa_1-xN nucleation layer, wherein an area of the semipolar nitride semiconductor film is substantially parallel to the substrate'"'"'s surface upon which the In_xGa_1-xN nucleation layer is deposited; and

(e) cooling the substrate under a nitrogen overpressure.

13. A device fabricated using the method of claim 12.

14. A planar semipolar nitride semiconductor film comprising semipolar nitride deposited on a nucleation layer comprising indium, wherein an area of the semipolar nitride semiconductor film is substantially parallel to a substrate surface upon which the (Al,In,Ga)N nucleation or buffer layer is grown.