Semiconductor device and method of fabricating the same and method of forming nitride based semiconductor layer

• US 20090114941A1
• Filed: 05/12/2008
• Published: 05/07/2009
• Est. Priority Date: 07/29/1998
• Status: Active Grant

• Current Assignee: Epistar Corporation
• Original Assignee: Sanyo Electric Company Limited (Panasonic Holdings Corporation)
• Inventors: Kano, Takashi, Hayashi, Nobuhiko
• Granted Patent: US 7,768,030 B2
• Time in Patent Office: Days
• US Class Current: 257/103
• CPC Class Codes: H01L 21/02164 the material being a silicon oxide, e.g. SiO2
• CPC Class Codes: H01L 21/31608 Deposition of SiO2 H01L21/31625, H01L21/31629 and H01L21/31633 take precedence
• CPC Class Codes: H01L 33/007 comprising nitride compounds
• CPC Class Codes: H01S 2304/12 Pendeo epitaxial lateral overgrowth [ELOG], e.g. for growing GaN based blue laser diodes
• CPC Class Codes: H01S 5/0216 using an intermediate compound, e.g. a glue or solder
• CPC Class Codes: H01S 5/0217 Removal of the substrate
• CPC Class Codes: H01S 5/32341 blue laser based on GaN or GaP

Abstract

A GaN layer is grown on a sapphire substrate, an SiO₂ film is formed on the GaN layer, and a GaN semiconductor layer including an MQW active layer is then grown on the GaN layer and the SiO₂ film using epitaxial lateral overgrowth. The GaN based semiconductor layer is removed by etching except in a region on the SiO₂ film, and a p electrode is then formed on the top surface of the GaN based semiconductor layer on the SiO₂ film, to join the p electrode on the GaN based semiconductor layer to an ohmic electrode on a GaAs substrate. An n electrode is formed on the top surface of the GaN based semiconductor layer.

Claims

1. A semiconductor device comprising:

a substrate;

a first electrode layer formed on said substrate;

a nitride based semiconductor layer formed on said first electrode layer and containing at least one of boron, gallium, aluminum and indium;

a second electrode layer formed on said nitride based semiconductor layer; and

a film for preventing short formed on a side surface of said nitride based semiconductor layer and said first electrode.

2. The semiconductor device according to claim 1, wherein

said nitride based semiconductor layer includes an active layer.

3. The semiconductor device according to claim 2, wherein

said nitride based semiconductor layer has a striped current injection region for injecting a current into said active layer,

said striped current injection region being formed along a <

1 100>

direction of said nitride based semiconductor layer.

4. The semiconductor device according to claim 1, wherein said film is composed of SiO₂.

5. The semiconductor device according to claim 3, wherein

said semiconductor device has a pair of cavity facets,

said cavity facet having a {1 100} plane of said nitride based semiconductor layer.

6. The semiconductor device according to claim 1, wherein said second electrode layer is formed on said film.

7. The semiconductor device according to claim 6, wherein said second electrode layer is formed on said film on said first electrode.

8. A method of fabricating a semiconductor device, comprising the steps of:

joining one surface of a nitride based semiconductor layer containing at least one of boron, gallium, aluminum and indium to one surface of a substrate with a first electrode layer sandwiched therebetween; and

removing a region of said nitride based semiconductor layer where dislocations extend in the vertical direction.

9. The method according to claim 8, further comprising the steps of

forming said nitride based semiconductor layer on an insulating substrate;

removing said insulating substrate from said nitride based semiconductor layer; and

forming a second electrode layer on said nitride based semiconductor layer.

10. The method according to claim 8, further comprising the step of

forming a film for preventing short on a side surface of said nitride based semiconductor layer and said first electrode.

11. The method according to claim 8, wherein

said nitride based semiconductor layer includes an active layer.

12. The method according to claim 11, wherein

said nitride based semiconductor layer has a striped current injection region for injecting a current into said active layer,

said striped current injection region being formed along a <

1 101>

direction of said nitride based semiconductor layer.

13. The method according to claim 10, wherein said film is composed of SiO₂.

14. The method according to claim 11, further comprising the step of forming a pair of cavity facets said nitride based semiconductor layer,

said cavity facet having a {1 100} plane of said nitride based semiconductor layer.

15. The method according to claim 10, wherein

said step of forming said second electrode layer includes forming said second electrode layer on said film.

16. The method according to claim 15, wherein

said step of forming said second electrode layer includes forming said second electrode layer on said film on said first electrode.