Method of fabricating nitride-based semiconductor light-emitting device and nitride-based semiconductor light-emitting device

• US 20070221932A1
• Filed: 09/20/2006
• Published: 09/27/2007
• Est. Priority Date: 03/22/2006
• Status: Abandoned Application

• Current Assignee: Sanyo Electric Company Limited (Panasonic Holdings Corporation)
• Original Assignee: Sanyo Electric Company Limited (Panasonic Holdings Corporation)
• Inventors: Kano, Takashi, Nomura, Yasuhiko, Hata, Masayuki
• Application Number:
  US11/523,531
• Publication Number:
  US 20070221932A1
• Time in Patent Office: Days
• US Class Current: 257/96
• CPC Class Codes: B82Y 20/00 Nanooptics, e.g. quantum optics or photonic crystals
• CPC Class Codes: H01L 33/0075 comprising nitride compounds
• CPC Class Codes: H01S 2301/176 Specific passivation layers on surfaces other than the emission facet
• CPC Class Codes: H01S 2304/04 MOCVD or MOVPE
• CPC Class Codes: H01S 2304/12 Pendeo epitaxial lateral overgrowth [ELOG], e.g. for growing GaN based blue laser diodes
• CPC Class Codes: H01S 5/0202 Cleaving
• CPC Class Codes: H01S 5/0207 Substrates having a special shape
• CPC Class Codes: H01S 5/04252 characterised by the material
• CPC Class Codes: H01S 5/04254 characterised by the shape
• CPC Class Codes: H01S 5/2201 in a specific crystallographic orientation
• CPC Class Codes: H01S 5/3063 using Mg
• CPC Class Codes: H01S 5/34333 with a well layer based on Ga(In)N or Ga(In)P, e.g. blue laser

Abstract

A method of fabricating a nitride-based semiconductor light-emitting device capable of suppressing reduction of characteristics and a yield is obtained. This method of fabricating a nitride-based semiconductor light-emitting device comprises steps of forming a groove portion on a nitride-based semiconductor substrate by selectively removing a prescribed region of a second region of the nitride-based semiconductor substrate other than a first region corresponding to a light-emitting portion of a nitride-based semiconductor layer up to a prescribed depth and forming the nitride-based semiconductor layer having a different composition from the nitride-based semiconductor substrate on the first region and the groove portion of the nitride-based semiconductor substrate.

Claims

1. A method of fabricating a nitride-based semiconductor light-emitting device, comprising steps of:

forming a groove portion on a nitride-based semiconductor substrate by selectively removing a prescribed region of a second region of said nitride-based semiconductor substrate other than a first region corresponding to a light-emitting portion of a nitride-based semiconductor layer formed on said nitride-based semiconductor substrate up to a prescribed depth; and

forming said nitride-based semiconductor layer having a different composition from said nitride-based semiconductor substrate on said first region and said groove portion of said nitride-based semiconductor substrate.

2. The method of fabricating a nitride-based semiconductor light-emitting device according to claim 1, wherein

said nitride-based semiconductor substrate includes a GaN substrate, and

said nitride-based semiconductor layer includes a layer containing Al, Ga and N.

3. The method of fabricating a nitride-based semiconductor light-emitting device according to claim 2, wherein

said step of forming said nitride-based semiconductor layer on said nitride-based semiconductor substrate includes a step of forming said nitride-based semiconductor layer on the upper surface of said first region of said nitride-based semiconductor substrate and the bottom surface and the side surface of said groove portion, and

the Al composition ratio of a portion of said nitride-based semiconductor layer formed on the side surface of said groove portion is lower than the Al composition ratio of a portion of said nitride-based semiconductor layer formed on the upper surface of said first region.

4. The method of fabricating a nitride-based semiconductor light-emitting device according to claim 3, wherein

said step of forming said groove portion on said nitride-based semiconductor substrate includes a step of forming said groove portion so that the opening width of said groove portion is gradually increased from the bottom surface toward the opening end of said groove portion.

5. The method of fabricating a nitride-based semiconductor light-emitting device according to claim 1, wherein

said step of forming said nitride-based semiconductor layer on said nitride-based semiconductor substrate includes a step of forming said nitride-based semiconductor layer on the upper surface of said first region of said nitride-based semiconductor substrate and the bottom surface and the side surface of said groove portion, and

the thickness of a portion of said nitride-based semiconductor layer formed on the side surface of said groove portion is smaller than the thickness of a portion of said nitride-based semiconductor layer formed on the upper surface of said first region.

6. The method of fabricating a nitride-based semiconductor light-emitting device according to claim 5, wherein

said step of forming said groove portion on said nitride-based semiconductor substrate includes a step of forming said groove portion so that the side surface of said groove portion is substantially perpendicular to the surface of said nitride-based semiconductor substrate.

7. The method of fabricating a nitride-based semiconductor light-emitting device according to claim 5, wherein

said step of forming said groove portion on said nitride-based semiconductor substrate includes a step of forming said groove portion so that the opening width of said groove portion is gradually reduced from the bottom surface toward the opening end of said groove portion.

8. The method of fabricating a nitride-based semiconductor light-emitting device according to claim 1, wherein

said step of forming said groove portion on said nitride-based semiconductor substrate includes a step of forming slender said groove portion extending in a prescribed direction on said nitride-based semiconductor substrate.

9. The method of fabricating a nitride-based semiconductor light-emitting device according to claim 1, wherein

the surface of said nitride-based semiconductor substrate has a (H,K,−

H−

K,L) plane (H and K are integers, and at least either H or K is nonzero).

10. The method of fabricating a nitride-based semiconductor light-emitting device according to claim 9, wherein

the surface of said nitride-based semiconductor substrate has a (H,K,−

H−

K,0) plane.

11. The method of fabricating a nitride-based semiconductor light-emitting device according to claim 9, wherein

the surface of said nitride-based semiconductor substrate has a (H,K,−

H−

K,L) plane (L is a nonzero integer).

12. The method of fabricating a nitride-based semiconductor light-emitting device according to claim 9, wherein

said step of forming said groove portion on said nitride-based semiconductor substrate includes a step of forming said groove portion extending along a [K,−

H,H−

K,0] direction on said nitride-based semiconductor substrate.

13. The method of fabricating a nitride-based semiconductor light-emitting device according to claim 1, wherein

said step of forming said groove portion on said nitride-based semiconductor substrate includes a step of latticing slender said groove portions extending in a first direction and a second direction intersecting with said first direction on said nitride-based semiconductor substrate to enclose said first region.

14. The method of fabricating a nitride-based semiconductor light-emitting device according to claim 1, wherein

said nitride-based semiconductor layer includes a layer, formed on said first region and said second region of said nitride-based semiconductor substrate, of a nitride-based semiconductor having a different composition from said nitride-based semiconductor substrate and a light-emitting layer of a nitride-based semiconductor formed at least on said first region.

15. A nitride-based semiconductor light-emitting device comprising:

a nitride-based semiconductor substrate including a first region corresponding to a light-emitting portion and a second region arranged to be adjacent to said first region through a step portion having a prescribed height; and

a nitride-based semiconductor layer, formed on the upper surface of said first region of said nitride-based semiconductor substrate and the side surface of said step portion, having a different composition from said nitride-based semiconductor substrate, wherein

the thickness of a portion of said nitride-based semiconductor layer formed on the side surface of said step portion is smaller than the thickness of a portion of said nitride-based semiconductor layer formed on the upper surface of said first region.

16. The nitride-based semiconductor light-emitting device according to claim 15, wherein

the surface of said nitride-based semiconductor substrate has a (H,K,−

H−

K,L) plane (H and K are integers, and at least either H or K is nonzero).

17. The nitride-based semiconductor light-emitting device according to claim 16, wherein

the surface of said nitride-based semiconductor substrate has a (H,K,−

H−

K,0) plane.

18. The nitride-based semiconductor light-emitting device according to claim 17, wherein

said step portion is so formed as to extend along a [K,−

H,H−

K,0] direction.

19. The nitride-based semiconductor light-emitting device according to claim 16, wherein

the surface of said nitride-based semiconductor substrate has a (H,K,−

H−

K,L) plane (L is a nonzero integer).

20. The nitride-based semiconductor light-emitting device according to claim 15, wherein

said nitride-based semiconductor layer includes a layer, formed on said first region and said second region of said nitride-based semiconductor substrate, of a nitride-based semiconductor having a different composition from said nitride-based semiconductor substrate and a light-emitting layer of a nitride-based semiconductor formed at least on said first region.

21. A nitride-based semiconductor light-emitting device comprising:

a nitride-based semiconductor substrate including a first region corresponding to a light-emitting portion and a second region arranged to be adjacent to said first region through a step portion having a prescribed height; and

a nitride-based semiconductor layer, formed on the upper surface of said first region of said nitride-based semiconductor substrate and the side surface of said step portion, having a different composition from said nitride-based semiconductor substrate and containing Al, Ga and N, wherein

the Al composition ratio of a portion of said nitride-based semiconductor layer formed on the side surface of said step portion is lower than the Al composition ratio of a portion of said nitride-based semiconductor layer formed on the upper surface of said first region.

22. The nitride-based semiconductor light-emitting device according to claim 21, wherein

the surface of said nitride-based semiconductor substrate has a (H,K,−

H−

K,L) plane (H and K are integers, and at least either H or K is nonzero).

23. The nitride-based semiconductor light-emitting device according to claim 22, wherein

the surface of said nitride-based semiconductor substrate has a (H,K,−

H−

K,0) plane.

24. The nitride-based semiconductor light-emitting device according to claim 22, wherein

the surface of said nitride-based semiconductor substrate has a (H,K,−

H−

K,L) plane (L is a nonzero integer).

25. The nitride-based semiconductor light-emitting device according to claim 24, wherein

said step portion is so formed as to extend along a [K,−

H,H−

K,0] direction.

26. The nitride-based semiconductor light-emitting device according to claim 21, wherein

said nitride-based semiconductor layer includes a layer, formed on said first region and said second region of said nitride-based semiconductor substrate, containing Al and Ga and a light-emitting layer of a nitride-based semiconductor formed at least on said first region.