Reflector, manufacture method thereof and light-emitting device including the reflector

• US 8,415,702 B2
• Filed: 09/15/2011
• Issued: 04/09/2013
• Est. Priority Date: 10/29/2010
• Status: Active Grant

• Current Assignee: Quanzhou Sanan Semiconductor Technology Co., Ltd. (Sanan Optoelectronics Company Limited)
• Original Assignee: Xiamen Sanan Optoelectronics Technology Company Limited (Sanan Optoelectronics Company Limited)
• Inventors: Pan, Qunfeng, Wu, Jyh-Chiarng, Lin, Kechuang
• Primary Examiner(s): Maldonado, Julio J
• Assistant Examiner(s): ESKRIDGE, CORY W
• Application Number:
  US13/233,367
• Publication Number:
  US 20120104410A1
• Time in Patent Office: 572 Days
• Field of Search: 257/12, 257/72, 257 79-103, 438/29
• US Class Current: 257/98
• CPC Class Codes: H01L 33/0093 Wafer bonding; Removal of the growth substrate
• CPC Class Codes: H01L 33/10 with a light reflecting structure, e.g. semiconductor Bragg reflector
• CPC Class Codes: H01L 33/22 Roughened surfaces, e.g. at the interface between epitaxial layers
• CPC Class Codes: H01L 33/46 Reflective coating, e.g. dielectric Bragg reflector

Abstract

A reflector for a GaN-based light-emitting device, method for manufacturing the reflector and GaN-based light-emitting device including the reflector are provided. The reflector is formed on a p-type GaN-based epitaxial layer and includes: a whisker crystal of un-doped GaN, formed on a surface of the p-type GaN-based epitaxial layer with a predefined density distribution and at a position that corresponds to a dislocation defect of an epitaxial layer; and a metal reflective layer, formed on both the p-type GaN-based epitaxial layer and the whisker crystal. The whisker of un-doped GaN is positioned on the dislocation defect of the p-type GaN-based epitaxial layer, so that the Ag reflective layer can be separated from the dislocation defect of the p-type GaN-based epitaxial layer, thereby effectively preventing Ag from moving inside the dislocation defect via electromigration, and largely decreasing the possibility of current leakage of the light-emitting device including the Ag reflector.

Claims

1. A reflector for a GaN-based light-emitting device, wherein the reflector is formed on a p-type GaN-based epitaxial layer and comprises:

a whisker crystal of un-doped GaN, formed on a surface of the p-type GaN-based epitaxial layer with a predefined density distribution and at a position that corresponds to a dislocation defect of an epitaxial layer wherein the epitaxial layer comprises the p-type GaN-based epitaxial, layer; and

a metal reflective layer, formed on both the p-type GaN-based epitaxial layer and the whisker crystal.

2. The reflector according to claim 1, wherein the metal reflective layer comprises Ag, an Ag alloy, or a combination thereof.

3. A GaN-based light-emitting device, comprising:

an epitaxial structure comprising an n-type GaN-based epitaxial layer, an active layer and a p-type GaN-based epitaxial layer; and

a p-type reflector at the side of the p-type GaN-based epitaxial layer, wherein the p-type reflector comprises;

a whisker crystal of un-doped GaN, formed on a surface of the p-type GaN-based epitaxial layer with a predefined density distribution and at, a position that corresponds to a dislocation defect of the epitaxial structure; and

a metal reflective layer, formed on both the p-type GaN-based epitaxial layer and the whisker crystal.

4. The GaN-based light-emitting device according to, claim 3, wherein the metal reflective layer comprises Ag, an Ag alloy, or a combination thereof.