LIGHT-EMITTING DEVICE HAVING A PATTERNED SUBSTRATE AND THE METHOD THEREOF

• US 20130009188A1
• Filed: 09/14/2012
• Published: 01/10/2013
• Est. Priority Date: 07/28/2006
• Status: Active Grant

• Current Assignee: Epistar Corporation
• Original Assignee: Epistar Corporation
• Inventors: Hsu, Ta-Cheng, Yang, Ya-Lan, Su, Ying-Yong, Yeh, Ching-Shian, Huang, Chao-Shun, Lee, Ya-Ju
• Granted Patent: US 9,231,151 B2
• Time in Patent Office: Days
• US Class Current: 257/98
• CPC Class Codes: H01L 33/007 comprising nitride compounds
• CPC Class Codes: H01L 33/22 Roughened surfaces, e.g. at the interface between epitaxial layers
• CPC Class Codes: H01L 33/32 containing nitrogen

Abstract

This disclosure provides a light-emitting device including a patterned substrate and the manufacturing method thereof. The patterned substrate has a plurality of depressions and/or extrusions for scattering light emitted from a light-emitting layer. Each of the plurality of depressions and/or extrusions comprises a top portion, a bottom portion, and a sidewall portion enclosing the top portion and the bottom portion, and at least part of the sidewall portion comprises a curve. Ina preferred embodiment, the light-emitting device further comprises a rough surface formed on at least one of the top portion, the bottom portion, and the sidewall portion.

Claims

1. A light-emitting device, comprising:

a textured substrate comprising a plurality of textured structures; and

a light-emitting stack overlaying the textured substrate, comprising a first conductivity type semiconductor layer, an active layer, and a second conductivity type semiconductor layer, wherein at least one of the plurality of textured structures comprises a top portion having a first shape and a bottom portion parallel to the top portion and having a second shape different from the first shape.

2. The light-emitting device according to claim 1, wherein the first shape comprises circle or ellipse.

3. The light-emitting device according to claim 1, wherein the second shape comprises polygon.

4. The light-emitting device according to claim 1, wherein the first shape comprises circle and the second shape comprises polygon.

5. The light-emitting device according to claim 1, wherein at least one of the top portion and the bottom portion comprises a flat plane.

6. The light-emitting device according to claim 1, wherein the textured substrate comprises sapphire.

7. The light-emitting device according to claim 6, wherein the flat plane comprises a sapphire C plane.

8. The light-emitting device according to claim 1, wherein the at least one of the plurality of textured structures further comprises a sidewall portion connecting the top portion and the bottom portion.

9. The light-emitting device according to claim 8, wherein the sidewall portion comprises a plurality of symmetric planes.

10. The light-emitting device according to claim 6, wherein the sidewall portion comprises a plurality of symmetric sapphire R-planes.

11. The light-emitting device according to claim 8, wherein a cross-section of the sidewall portion near the top portion is a curve.

12. The light-emitting device according to claim 8, wherein a cross-section of the sidewall portion near the bottom portion is a curve.

13. The light-emitting device according to claim 8, wherein a cross-section of the bottom portion is rounded.

14. The light-emitting device according to claim 1, wherein the light-emitting stack comprises a III-nitride compound.