Method of manufacturing vertical gallium nitride-based light emitting diode

• US 7,687,376 B2
• Filed: 04/06/2007
• Issued: 03/30/2010
• Est. Priority Date: 05/10/2006
• Status: Expired due to Fees

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electro-Mechanics Co., Ltd. (Samsung Group)
• Inventors: Choi, Pun Jae, Lee, Jong Ho
• Primary Examiner(s): Toledo; Fernando L
• Assistant Examiner(s): Singal; Ankush k
• Application Number:
  US11/697,537
• Publication Number:
  US 20070264733A1
• Time in Patent Office: 1,089 Days
• Field of Search: 438/478
• US Class Current: 438/478
• CPC Class Codes: H01L 33/0075 comprising nitride compounds
• CPC Class Codes: H01L 33/0093 Wafer bonding; Removal of the growth substrate
• CPC Class Codes: H01L 33/22 Roughened surfaces, e.g. at the interface between epitaxial layers

Abstract

A method of manufacturing a vertical GaN-based LED comprises preparing an n-type GaN substrate; sequentially forming an active layer and a p-type nitride semiconductor layer on the n-type GaN substrate through an epitaxial growth method; forming a p-electrode on the p-type nitride semiconductor layer; wet-etching the lower surface of the n-type GaN substrate so as to reduce the thickness of the n-type GaN substrate; forming a flat n-type bonding pad on the wet-etched lower surface of the n-type GaN substrate, the n-type bonding pad defining an n-electrode formation region; and forming an n-electrode on the n-type bonding pad.

Claims

1. A method of manufacturing a vertical GaN-based LED comprising:

preparing an n-type GaN substrate;

sequentially forming an active layer and a p-type nitride semiconductor layer on the n-type GaN substrate through an epitaxial growth method;

forming a p-electrode on the p-type nitride semiconductor layer;

forming a p-type bonding pad on the p-electrode and forming a substrate support layer on the resulting structure in which the p-type bonding pad is formed, before the wet-etching of the n-type GaN substrate;

wet-etching the lower surface of the n-type GaN substrate so as to reduce the thickness of the n-type GaN substrate;

forming a flat n-type bonding pad on the wet-etched lower surface of the n-type GaN substrate, the n-type bonding pad defining an n-electrode formation region; and

forming an n-electrode on the n-type bonding pad;

wherein the active layer and the p-type nitride semiconductor layer have a lattice constant close to the lattice constant of the n-type GaN substrate; and

wherein forming the n-type bonding pad includes a plating method.

2. The method according to claim 1,

wherein the wet-etching of the n-type GaN substrate is performed so that surface irregularities are formed on the lower surface of the n-type GaN substrate.

3. The method according to claim 1 further comprising forming an n-type nitride semiconductor layer before the forming of the active layer.

4. The method according to claim 1, wherein the substrate support layer is formed by using a plating method.

5. The method according to claim 2,

wherein the surface irregularities are formed to have a height of more than 1 μ

m.

6. The method according to claim 2,

wherein the wet-etching of the n-type GaN substrate is performed by any one selected from the group consisting of a chemical wet etching method, an electro-chemical wet etching method, and an optical chemical wet etching method or may be performed by a combination of more than two wet etching methods.

7. The method according to claim 6, wherein the wet-etching is performed by using an etching solution such as KOH or H₃PO₄ solution.

8. The method according to claim 7,

wherein the wet etching is performed by using an etching solution having temperature of more than 50°

C.