Method of fabricating semiconductor laser

• US 8,012,780 B2
• Filed: 07/10/2008
• Issued: 09/06/2011
• Est. Priority Date: 08/13/2007
• Status: Active Grant

• Current Assignee: Sumitomo Electric Industries Limited (Sumitomo Corporation)
• Original Assignee: Sumitomo Electric Industries Limited (Sumitomo Corporation)
• Inventors: Matsubara, Hideki, Yoshimoto, Susumu
• Primary Examiner(s): Toledo; Fernando L
• Application Number:
  US12/170,998
• Publication Number:
  US 20090047751A1
• Time in Patent Office: 1,153 Days
• Field of Search: 438/29, 438/32, 359/566, 372/99, 385/37
• US Class Current: 438/29
• CPC Class Codes: B82Y 20/00 Nanooptics, e.g. quantum optics or photonic crystals
• CPC Class Codes: H01S 5/1017 Waveguide having a void for insertion of materials to change optical properties
• CPC Class Codes: H01S 5/11 Comprising a photonic bandgap structure
• CPC Class Codes: H01S 5/1231 Grating growth or overgrowth details
• CPC Class Codes: H01S 5/2009 by using electron barrier layers
• CPC Class Codes: H01S 5/34333 with a well layer based on Ga(In)N or Ga(In)P, e.g. blue laser

Abstract

There is provided a method of fabricating a semiconductor laser including a two-dimensional photonic crystal. The method comprises the steps of growing an In_X1Ga_1−X1N (0<X1<1) layer on a gallium nitride-based semiconductor region in a reactor; after taking out a substrate product including the In_X1Ga_1−X1N layer from the reactor, forming a plurality of openings for a two-dimensional diffraction grating of the two-dimensional photonic crystal in the In_X1Ga_1−X1N layer to form a patterned In_X1Ga_1−X1N layer; and growing an Al_X2Ga_1−X2N (0≦X2≦1) layer on a top surface of the patterned In_X1Ga_1−X1N layer to form voids associated with the openings.

Claims

1. A method of fabricating a semiconductor laser including a two-dimensional photonic crystal, the method comprising the steps of:

growing an In_X1Ga<sub>1−

X1</sub>N (0<

X1<

1) layer on a gallium nitride-based semiconductor region in a reactor to form a substrate product;

after taking out, from the reactor, the substrate product including the In_X1Ga<sub>1−

X1</sub>N layer, forming a plurality of openings for a two-dimensional diffraction grating of the two-dimensional photonic crystal in the In_X1Ga<sub>1−

X1</sub>N layer to form a patterned In_X1Ga<sub>1−

X1</sub>N layer; and

growing an Al_X2Ga<sub>1−

X2</sub>N (0≦

X2≦

1) layer on the patterned In_X1Ga<sub>1−

X1</sub>N layer so as to form voids from the openings.

2. The method according to claim 1, wherein a side and a bottom of each opening comprise InGaN.

3. The method according to claim 1, further comprising the step of, after growing the In_X1Ga₁₋

X1N layer and prior to forming the plurality of the openings for the two-dimensional diffraction grating in the In_X1Ga<sub>1−

X1</sub>N layer, growing a GaN layer on the In_X1Ga<sub>1−

X1</sub>N layer, the substrate product including the GaN layer, the plurality of the openings being formed in the In_X1Ga<sub>1−

X1</sub>N layer and the GaN layer.

4. The method according to claim 1, further comprising a step of, prior to the formation of the Al_X2Ga₁₋

X2N layer, forming a dielectric layer, the dielectric layer covering bottom surfaces of the openings, the substrate product including the dielectric layer.

5. The method according to claim 4, wherein a top surface of the In_X1Ga₁₋

X1N layer is in contact with the Al_X2Ga<sub>1−

X2</sub>N layer.

6. The method according to claim 4, wherein

the dielectric layer includes at least one of a silicon oxide layer, a silicon oxynitride layer, a silicon nitride layer, a zirconium oxide layer, a titanium oxide layer, and a hafnium oxide layer.

7. The method according to claim 2, further comprising a step of, prior to the formation of the Al_X2Ga₁₋

X2N layer, forming a dielectric layer, the dielectric layer covering bottom surfaces of the openings, the substrate product including the dielectric layer.

8. The method according to claim 7, wherein a top surface of the In_X1Ga₁₋

X1N layer is in contact with the Al_X2Ga<sub>1−

X2</sub>N layer.

9. The method according to claim 7, wherein the dielectric layer includes at least one of a silicon oxide layer, a silicon oxynitride layer, a silicon nitride layer, a zirconium oxide layer, a titanium oxide layer, and a hafnium oxide layer.

10. The method according to claim 3, further comprising a step of, prior to the formation of the Al_X2Ga₁₋

X2N layer, forming a dielectric layer, the dielectric layer covering bottom surfaces of the openings, the substrate product including the dielectric layer.

11. The method according to claim 10, wherein a top surface of the In_X1Ga₁₋

X1N layer is in contact with the Al_X2Ga<sub>1−

X2</sub>N layer.

12. The method according to claim 10, wherein the dielectric layer includes at least one of a silicon oxide layer, a silicon oxynitride layer, a silicon nitride layer, a zirconium oxide layer, a titanium oxide layer, and a hafnium oxide layer.

13. The method according to claim 1, wherein the Al_X2Ga₁₋

X2N layer is a GaN layer.

14. The method according to claim 1, further comprising the step of, after growing the Al_X2Ga₁₋

X2N layer, growing an active layer.

15. The method according to claim 1, further comprising the step of, prior to growing the In_X1Ga₁₋

X1N layer, growing an active layer.

16. The method according to claim 1, wherein a top surface of the In_X1Ga₁₋

X1N layer is in contact with the Al_X2Ga<sub>1−

X2</sub>N layer.

17. The method according to claim 1, wherein the Al_X2Ga₁₋

X2N layer is grown on the In_X1Ga<sub>1−

X1</sub>N layer such that the Al_X2Ga<sub>1−

X2</sub>N layer closes the openings to form the voids.

18. The method according to claim 1, wherein the In_X1Ga₁₋

X1N layer is covered with the Al_X2Ga<sub>1−

X2</sub>N layer without filling the openings to form the voids.

19. The method according to claim 1, wherein the voids are arranged in a triangle grating.

20. The method according to claim 1, wherein the voids are arranged in a square grating.