Method of manufacturing substrate for forming device, and method of manufacturing nitride-based semiconductor laser diode

• US 20090155945A1
• Filed: 03/04/2008
• Published: 06/18/2009
• Est. Priority Date: 12/17/2007
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electro-Mechanics Co., Ltd. (Samsung Group)
• Inventors: Paek, Ho Sun, Sung, Youn Joon
• Granted Patent: US 8,163,579 B2
• Time in Patent Office: Days
• US Class Current: 438/33
• CPC Class Codes: H01S 5/0201 Separation of the wafer into individual elements, e.g. by dicing, cleaving, etching or directly during growth
• CPC Class Codes: H01S 5/0202 Cleaving
• CPC Class Codes: H01S 5/0213 Sapphire, quartz or diamond based substrates
• CPC Class Codes: H01S 5/32025 non-polar orientation
• CPC Class Codes: H01S 5/32341 blue laser based on GaN or GaP

Abstract

Provided is a method of manufacturing a semiconductor laser diode. The method includes the steps of: preparing a GaN substrate having an a-plane or m-plane GaN layer formed thereon; forming a plurality of laser diode structures on the GaN layer; etching the GaN substrate such that a cutting reference line is formed in a groove shape along the crystal surface of the a-plane or m-plane, not a main plane; and cutting the GaN substrate along the cutting reference line so as to form a mirror surface of the semiconductor laser diode, the mirror surface coinciding with the crystal surface of the a-plane or m-plane, not the main plane.

Claims

1. A method of manufacturing a substrate for forming a device, the method comprising the steps of:

preparing a GaN substrate of which the a-plane or m-plane is set to a main plane;

masking the main plane of the GaN substrate; and

applying the masked GaN substrate to etching liquid, thereby forming a crystallographic surface.

2. The method according to claim 1, wherein KOH is used as the etching liquid.

3. A method of manufacturing a semiconductor laser diode, the method comprising the steps of:

preparing a GaN substrate having an a-plane or m-plane GaN layer formed thereon;

forming a plurality of laser diode structures on the GaN layer;

etching the GaN substrate such that a cutting reference line is formed in a groove shape along the crystal surface of the a-plane or m-plane, not a main plane; and

cutting the GaN substrate along the cutting reference line so as to form a mirror surface of the semiconductor laser diode, the mirror surface coinciding with the crystal surface of the a-plane or m-plane, not the main plane.

4. The method according to claim 3, wherein the preparing of the GaN substrate includes the steps of:

preparing an r-plane sapphire substrate; and

forming an a-plane or m-plane GaN layer on the r-plane sapphire substrate.

5. The method according to claim 3, where the etching of the GaN substrate includes the steps of:

applying a mask onto the GaN substrate having laser diode structures formed thereon such that a region where the cutting reference line is to be formed is exposed; and

wet-etching the GaN substrate exposed through the mask such that the GaN substrate is etched along the crystal surface of a c-plane <

0001>

.

6. The method according to claim 5, wherein the wet etching is performed using KOH etching liquid.

7. The method according to claim 3, wherein the cutting reference line is formed by etching only portion of the GaN substrate in the thickness direction of the GaN substrate.

8. The method according to claim 3, wherein the cutting reference line is formed by etching the GaN substrate such that the sapphire substrate is exposed.