Light emitting device and method of manufacturing the same

• US 9,343,624 B2
• Filed: 11/24/2014
• Issued: 05/17/2016
• Est. Priority Date: 03/07/2006
• Status: Active Grant

• Current Assignee: Suzhou Lekin Semiconductor Company Limited
• Original Assignee: LG Electronics, Inc. (LG Corporation), LG Innotek Company Limited (LG Corporation)
• Inventors: Kim, Jong Wook, Cho, Hyun Kyong, Yi, Gyu Chul, An, Sung Jin, Yoo, Jin Kyoung, Hong, Young Joon
• Primary Examiner(s): POTTER, ROY KARL
• Application Number:
  US14/552,088
• Publication Number:
  US 20150102370A1
• Time in Patent Office: 540 Days
• US Class Current: 1/1
• CPC Class Codes: H01L 21/0237 Materials
• CPC Class Codes: H01L 21/0242 Crystalline insulating materials
• CPC Class Codes: H01L 21/02458 Nitrides
• CPC Class Codes: H01L 21/0254 Nitrides
• CPC Class Codes: H01L 21/0262 Reduction or decomposition of gaseous compounds, e.g. CVD
• CPC Class Codes: H01L 33/22 Roughened surfaces, e.g. at the interface between epitaxial layers
• CPC Class Codes: H01L 33/32 containing nitrogen
• CPC Class Codes: H01L 33/36 characterised by the electrodes
• CPC Class Codes: H01L 33/60 Reflective elements

Abstract

A light emitting device is disclosed. The light emitting device includes a conductive support layer; a reflective layer disposed on the conductive support layer; a nitride semiconductor layer disposed on the reflective layer. Furthermore, the nitride semiconductor layer includes a second-type semiconductor layer on the reflective layer, an active layer on the second-type semiconductor layer, and a first-type semiconductor layer on the active layer; a light extraction structure disposed on the first-type semiconductor layer; and a first-type electrode disposed on the light extraction structure.

Claims

1. A light emitting device, comprising:

a conductive support layer;

a reflective layer disposed on the conductive support layer;

a nitride semiconductor layer disposed on the reflective layer, wherein the nitride semiconductor layer includes a second-type semiconductor layer on the reflective layer, an active layer on the second-type semiconductor layer, and a first-type semiconductor layer on the active layer;

a light extraction structure disposed on the first-type semiconductor layer; and

a first-type electrode disposed next to the light extraction structure.

2. The light emitting device of claim 1, wherein the light extraction structure includes a plurality of cones.

3. The light emitting device of claim 2, wherein a top of any of the cones is higher than a middle between a top surface of the first-type electrode and a bottom surface of the first-type electrode, on a top surface of the first-type semiconductor layer.

4. The light emitting device of claim 1, wherein the conductive support layer includes a soft metal and a hard metal.

5. The light emitting device of claim 4, wherein the soft metal includes Au, Cu, Ag, and Al.

6. The light emitting device of claim 4, wherein the hard metal includes Ni, Co, Pt, and Pd.

7. The light emitting device of claim 1, wherein the reflective layer includes a metal.

8. The light emitting device of claim 7, wherein the metal includes Ni and Au.

9. The light emitting device of claim 1, wherein the reflective layer has a specific contact resistance of 10-3 Ω

cm2 to 10-4 Ω

cm2.

10. The light emitting device of claim 2, wherein the cones are disposed under and beside the first-type electrode.

11. The light emitting device of claim 2, wherein at least one of the cones is a nano scale cone.

12. The light emitting device of claim 11, wherein the nano scale cone has a size of 10 nm to 1000 nm.

13. The light emitting device of claim 2, wherein the cones are made of a nitride semiconductor material.

14. The light emitting device of claim 13, wherein the nitride semiconductor material of the cones has a formula of AlxInyGa(1-x-y)N (where, 0≦

x≦

1, 0≦

y≦

1, and 0≦

x+y≦

1).

15. The light emitting device of claim 2, wherein the at least one of the cones is formed with a shape of a pyramid.

16. The light emitting device of claim 1, wherein the active layer includes InGaN, and at least one of the first-type semiconductor layer or the second-type semiconductor layer includes AlGaN.

17. The light emitting device of claim 1, wherein the light extraction structure includes substantially the same material as that of the nitride semiconductor layer.

18. The light emitting device of claim 1, wherein the light extraction structure is a part of the nitride semiconductor layer.

19. The light emitting device of claim 2, wherein the cones do not overlap each other.

20. The light emitting device of claim 1, wherein the light extraction structure is disposed on an entire upper surface of the first-type semiconductor layer.