Gallium nitride based compound semiconductor light-emitting device and method for manufacturing same

• US 8,026,118 B2
• Filed: 12/12/2006
• Issued: 09/27/2011
• Est. Priority Date: 12/14/2005
• Status: Active Grant

• Current Assignee: Toyoda Gosei Company Limited (Toyota Motor Corporation)
• Original Assignee: Showa Denko KK
• Inventors: Osawa, Hiroshi, Shinohara, Hironao
• Primary Examiner(s): Wilson; Allan R
• Application Number:
  US12/096,827
• Publication Number:
  US 20090309119A1
• Time in Patent Office: 1,750 Days
• Field of Search: 257/103, 257/E33.025, 257/E21.217, 257/E21.218, 438/46, 438/720
• US Class Current: 438/46
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2224/48247 connecting the wire to a bond pad of the item
• CPC Class Codes: H01L 2224/48257 connecting the wire to a die pad of the item
• CPC Class Codes: H01L 2224/49107 on the semiconductor or solid-state body
• CPC Class Codes: H01L 2224/73265 Layer and wire connectors
• CPC Class Codes: H01L 2924/00012 Relevant to the scope of the group, the symbol of which is combined with the symbol of this group
• CPC Class Codes: H01L 2924/00014 the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed without further technical details
• CPC Class Codes: H01L 2924/181 Encapsulation
• CPC Class Codes: H01L 2933/0016 relating to electrodes
• CPC Class Codes: H01L 33/22 Roughened surfaces, e.g. at the interface between epitaxial layers
• CPC Class Codes: H01L 33/32 containing nitrogen
• CPC Class Codes: H01L 33/38 with a particular shape
• CPC Class Codes: H01L 33/42 Transparent materials

Abstract

The present invention provides a gallium nitride based compound semiconductor light-emitting device having high light emission efficiency and a method of manufacturing the same. The gallium nitride based compound semiconductor light-emitting device includes: a substrate 11; an n-type semiconductor layer 13, a light-emitting layer 14, and a p-type semiconductor layer 15 that are composed of gallium nitride based compound semiconductors and formed on the substrate 11 in this order; a transparent positive electrode 16 that is formed on the p-type semiconductor layer 15; a positive electrode bonding pad 17 that is formed on the transparent positive electrode 16; a negative electrode bonding pad 18 that is formed on the n-type semiconductor layer 13; and an uneven surface that has random convex portions formed thereon and is provided on at least a portion of the surface 16a of the transparent positive electrode 16.

Claims

1. A method of manufacturing a gallium nitride based compound semiconductor light-emitting device, the method comprising:

(1) a process of sequentially forming on a substrate an n-type semiconductor layer, a light-emitting layer, and a p-type semiconductor layer, and a transparent positive electrode, the n-type semiconductor layer, the light-emitting layer, and the p-type semiconductor layer each composed of a gallium nitride based compound semiconductor;

(2) a process of forming a mask made of metal particles on the surface of the transparent positive electrode; and

(3) a process of performing dry etching on the transparent positive electrode using the mask,

wherein the metal particles of the mask are made of Ni, or a Ni alloy.

2. The method of manufacturing a gallium nitride based compound semiconductor light-emitting device according to claim 1,

wherein the process (2) includes:

forming a metal thin film on the surface of the transparent positive electrode; and

performing a heat treatment.

3. The method of manufacturing a gallium nitride based compound semiconductor light-emitting device according to claim 1,

wherein an uneven surface is formed on at least a portion of the surface of the transparent positive electrode by wet etching.

4. A lamp comprising the gallium nitride based compound semiconductor light-emitting device manufactured by the method according to claim 1.