Light-emitting devices

• US 9,048,379 B2
• Filed: 12/02/2013
• Issued: 06/02/2015
• Est. Priority Date: 08/30/2010
• Status: Active Grant

• Current Assignee: Epistar Corporation
• Original Assignee: Epistar Corporation
• Inventors: Chen, Chao-Hsing, Yang, Yu-Chen, Jou, Li-Ping, Yeh, Hui-Chun, Ku, Yi-Wen
• Primary Examiner(s): Yang, Minchul
• Application Number:
  US14/093,924
• Publication Number:
  US 20140084324A1
• Time in Patent Office: 547 Days
• Field of Search: 257/79, 257/98, 257/99, 257/E33.068, 257/E33.072
• US Class Current: 1/1
• CPC Class Codes: H01L 33/0012 p-i-n devices
• CPC Class Codes: H01L 33/08 with a plurality of light emitting regions, e.g. laterally discontinuous light emitting layer or photoluminescent region integrated within the semiconductor body H01L27/15 takes precedence
• CPC Class Codes: H01L 33/20 with a particular shape, e.g. curved or truncated substrate
• CPC Class Codes: H01L 33/30 containing only elements of Group III and Group V of the Periodic Table
• CPC Class Codes: H01L 33/38 with a particular shape
• CPC Class Codes: H01L 33/382 the electrode extending partially in or entirely through the semiconductor body
• CPC Class Codes: H01L 33/44 characterised by the coatings, e.g. passivation layer or anti-reflective coating
• CPC Class Codes: H01L 33/46 Reflective coating, e.g. dielectric Bragg reflector
• CPC Class Codes: H01L 33/60 Reflective elements
• CPC Class Codes: H01L 33/62 Arrangements for conducting electric current to or from the semiconductor body, e.g. lead-frames, wire-bonds or solder balls

Abstract

A light-emitting device of an embodiment of the present application comprises a semiconductor layer sequence provided with a first main side, a second main side, and an active layer; a beveled trench formed in the semiconductor layer sequence, having a top end close to the second main side, a bottom end, and an inner sidewall connecting the top end and the bottom end. In the embodiment, the inner sidewall is an inclined surface. The light-emitting device further comprises a dielectric layer disposed on the inner sidewall of the beveled trench and the second main side; a first metal layer formed on the dielectric layer; a carrier substrate; and a first connection layer connecting the carrier substrate and the semiconductor layer sequence.

Claims

1. A light-emitting device, comprising:

a semiconductor layer sequence comprising a first semiconductor layer having a first electrical conductivity, a second semiconductor layer having a second electrical conductivity, and an active layer interposed between the first semiconductor layer and the second semiconductor layer;

a protruding structure;

a beveled trench in the semiconductor layer sequence and accommodating the protruding structure;

a dielectric layer on the second semiconductor layer and an inner sidewall of the beveled trench;

a first metal layer on the dielectric layer and contacting with the first semiconductor layer, wherein the first metal layer is insulated from the second semiconductor layer by the dielectric layer;

a void formed between the first metal layer and the protruding structure;

a carrier substrate; and

a first connection layer connecting the carrier substrate and the semiconductor layer sequence,

wherein the second semiconductor layer is closer to he carrier substrate than the first semiconductor layer is to the carrier substrate.

2. The light-emitting device according to claim 1, wherein the protruding structure is surrounded by the first metal layer.

3. The light-emitting device according to claim 1, wherein the first metal layer is formed between the protruding structure and the dielectric layer.

4. The light-emitting device according to claim 1, wherein the protruding structure directly contacts with the first semiconductor layer.

5. The light-emitting device according to claim 1, wherein part of the first metal layer contacts with the protruding structure.

6. The light-emitting device according to claim 1, wherein the protruding structure comprises a layer sequence substantially comprising the same material as the semiconductor layer sequence.

7. The light-emitting device according to claim 1, wherein the top view of the beveled trench is circular or elliptic.

8. The light-emitting device according to claim 1, wherein the top view of the protruding structure is circular or elliptic.

9. The light-emitting device according to claim 1, wherein the circumference of the protruding structure is smaller than the circumference of the beveled trench.

10. The light-emitting device according to claim 1, wherein the material of the protruding structure comprises metal.

11. The light-emitting device according to claim 1, wherein the inner sidewall of the beveled trench is an inclined surface.

12. The light-emitting device according to claim 1, wherein the material of the first connection layer comprises metal.

13. The light-emitting device according to claims 1, wherein the active layer comprises InGaN-based material, AlGaAs-based material, or AlInGaP-based material.

14. The light-emitting device according to claim 1, wherein the carrier substrate is conductive.

15. The light-emitting device according to claim 1, further comprising a reflecting layer interposed between the semiconductor layer sequence and the dielectric layer.

16. The light-emitting device according to claim 15, further comprising a second electrode electrically connected to the second semiconductor layer.

17. The light-emitting device according to claim 16 wherein the reflecting layer having a portion beyond the semiconductor layer sequence and the second electrode is on the portion of the reflecting layer.

18. The light-emitting device according to claim 1, further comprising a first electrode formed on the carrier substrate and electrically connected to the first semiconductor layer.

19. The light-emitting device according to claim 1, wherein the first connection layer is formed between the first metal layer and the carrier substrate.