NITRIDE SEMICONDUCTOR CRYSTAL WITH SURFACE TEXTURE

• US 20120077298A1
• Filed: 12/06/2011
• Published: 03/29/2012
• Est. Priority Date: 08/28/2006
• Status: Active Grant

• Current Assignee: Stanley Electric Company Limited
• Original Assignee: Stanley Electric Company Limited
• Inventors: LIANG, Ji-Hao, Tsuchiya, Masahiko, Chinone, Takako, Kajikawa, Masataka
• Granted Patent: US 8,658,440 B2
• Time in Patent Office: Days
• US Class Current: 438/46
• CPC Class Codes: H01L 33/0075 comprising nitride compounds
• CPC Class Codes: H01L 33/08 with a plurality of light emitting regions, e.g. laterally discontinuous light emitting layer or photoluminescent region integrated within the semiconductor body H01L27/15 takes precedence
• CPC Class Codes: H01L 33/24 of the light emitting region, e.g. non-planar junction
• CPC Class Codes: H01L 33/32 containing nitrogen

Abstract

A nitride semiconductor light emitting device is formed by: forming a resist pattern on a first nitride semiconductor layer formed on a substrate, the resist pattern having a region whose inclination angle relative to a substrate surface changes smoothly as viewed in a cross section perpendicular to the substrate surface; etching the substrate by using the resist pattern as a mask to transfer the resist pattern to the first nitride semiconductor layer; and forming an light emitting layer on the patterned first nitride semiconductor layer. The nitride semiconductor light emitting device can emit near-white light or have a wavelength range generally equivalent to or near visible light range.

Claims

1. A method for manufacturing a nitride semiconductor light emitting device, the method comprising:

forming a resist pattern on a first nitride semiconductor layer formed above a substrate, said resist pattern having a region whose inclination angle of an upper surface relative to a substrate surface changes smoothly as viewed in a cross section perpendicular to the substrate surface;

etching said substrate by using said resist pattern as a mask to transfer said resist pattern to said first nitride semiconductor layer; and

forming an active layer on said patterned first nitride semiconductor layer.

2. The method according to claim 1, wherein forming the resist pattern comprises:

coating a resist layer on said first nitride semiconductor layer; and

exposing and developing said resist layer to form said resist pattern having said region.

3. The method for manufacturing a nitride semiconductor light emitting device according to claim 2, wherein said active layer includes an n-type nitride semiconductor layer, a p-type nitride semiconductor layer, and a plurality of light emitting regions having different light emission wavelength ranges.

4. The method according to claim 3, wherein said inclination angle is 0°

to 30°

along an a-axis direction or 0°

to 90°

along an M-axis direction.

5. The method according to claim 4, wherein said resist pattern has a plurality of projections.

6. The method according to claim 5, wherein said projections are disposed in a hexagonal close-packed configuration.

7. The method according to claim 5, wherein said projections are rib-like stripes.

8. A method for manufacturing a nitride semiconductor crystal, the method comprising:

forming a resist pattern on a first nitride semiconductor layer formed above a substrate, said resist pattern having a region whose inclination angle of an upper surface relative to a substrate surface changes smoothly as viewed in a cross section perpendicular to the substrate surface;

etching said substrate by using said resist pattern as a mask to transfer said resist pattern to said first nitride semiconductor layer; and

forming an active layer on said patterned first nitride semiconductor layer.

9. The method according to claim 8, wherein forming the resist pattern comprises:

coating a resist layer on said first nitride semiconductor layer; and

exposing and developing said resist to form said resist pattern having said region.

10. The method according to claim 9, wherein said active layer includes an n-type nitride semiconductor layer, a p-type nitride semiconductor layer, and a plurality of light emitting regions having different light emission wavelength ranges.