METHOD OF MANUFACTURING VERTICAL GALLIUM NITRIDE-BASED LIGHT EMITTING DIODE

• US 20070264733A1
• Filed: 04/06/2007
• Published: 11/15/2007
• Est. Priority Date: 05/10/2006
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electro-Mechanics Co., Ltd. (Samsung Group)
• Inventors: LEE, Jong Ho, CHOI, Pun Jae
• Granted Patent: US 7,687,376 B2
• Time in Patent Office: Days
• US Class Current: 438/22
• 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;

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.

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 2,

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

m.

4. 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.

5. The method according to claim 4,

wherein the wet-etching is performed by using an etching solution such as KOH or H₃PO₄ solution.

6. The method according to claim 5,

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

C.

7. The method according to claim 1 further comprising

forming an n-type nitride semiconductor layer before the forming of the active layer.

8. The method according to claim 1 further comprising

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.

9. The method according to claim 8,

wherein the substrate support layer is formed by using a plating method.