Light emitting device, method of manufacturing the same, light emitting apparatus, and lighting system

• US 8,637,884 B2
• Filed: 03/09/2010
• Issued: 01/28/2014
• Est. Priority Date: 03/10/2009
• Status: Active Grant

• Current Assignee: Suzhou Lekin Semiconductor Company Limited
• Original Assignee: LG Innotek Company Limited (LG Corporation)
• Inventors: Park, Duk Hyun
• Primary Examiner(s): Dickey, Thomas L
• Assistant Examiner(s): Schoenholtz, Joseph
• Application Number:
  US12/720,059
• Publication Number:
  US 20100230702A1
• Time in Patent Office: 1,421 Days
• Field of Search: None
• US Class Current: 257/98
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2924/00014 the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed without further technical details
• CPC Class Codes: H01L 33/0093 Wafer bonding; Removal of the growth substrate
• CPC Class Codes: H01L 33/20 with a particular shape, e.g. curved or truncated substrate
• CPC Class Codes: H01L 33/46 Reflective coating, e.g. dielectric Bragg reflector

Abstract

Disclosed is a light emitting device including a conductive substrate; a reflective layer on the conductive substrate; an etching protective layer on a peripheral portion of a top surface of the conductive substrate; and a light emitting structure, which is formed on the reflective layer and the etching protective layer such that the etching protective layer is partially exposed and includes a first conductive semiconductor layer, a second conductive semiconductor layer and an active layer between the first and second conductive semiconductor layers, wherein the etching protective layer includes a first refractive layer having a first refractive index and a second refractive layer having a second refractive index greater than the first refractive index.

Claims

1. A light emitting device comprising:

a conductive substrate;

a reflective layer on the conductive substrate;

an etching protective layer on the conductive substrate, the etching protective layer having an outer edge and an inner edge; and

a light emitting structure, which is formed on the reflective layer and the etching protective layer such that the etching protective layer is partially exposed and includes a first conductive semiconductor layer, a second conductive semiconductor layer and an active layer between the first and second conductive semiconductor layers; and

a bonding layer between the conductive substrate and the reflective layer,

wherein the etching protective layer includes a first refractive layer having a first refractive index and a second refractive layer having a second refractive index greater than the first refractive index, and

wherein a bottom surface of the reflective layer is flush with a bottom surface of the etching protective layer.

2. The light emitting device of claim 1, wherein the first and second refractive layers are stacked alternately.

3. The light emitting device of claim 1, wherein the first refractive layer includes at least one of SiO₂ and Al₂O₃.

4. The light emitting device of claim 1, wherein the second refractive layer includes at least one of Si, Si—

H, Si₃N₄, SiN, TiO₂ and ZrO₂.

5. The light emitting device of claim 1, further comprising a nitride semiconductor layer having a light extraction structure on the light emitting structure.

6. The light emitting device of claim 1, wherein at least two pairs of first and second refractive layers are provided.

7. The light emitting device of claim 1, wherein the first and second refractive layers have thickness of mλ

/4n respectively, in which λ

is a wavelength of light emitted from the light emitting structure, n is a refractive index of the first refractive layer or the second refractive layer, and m is an odd number.

8. The light emitting device of claim 1, wherein the first refractive layer is thicker than the second refractive layer.

9. A lighting system comprising:

a light emitting device package including the light emitting device of claim 1;

a substrate on which the light emitting device package is arranged; and

at least one of optical members selected from group consisting of a light guide plate, a prism sheet and a diffusion sheet, the at least one of optical members being arranged in a path of light emitted from the light emitting device package.

10. The light emitting device of claim 1, wherein the first refractive layer is disposed on the bonding layer.

11. The light emitting device of claim 1, wherein the light emitting structure is disposed on the second refractive layer.

12. The light emitting device of claim 1, wherein the etching protective layer is disposed only on a peripheral portion of a top surface of the bonding layer.

13. The light emitting device of claim 1, further comprising an electrode on the light emitting structure,

wherein the etching protective layer does not vertically overlap with the electrode.

14. The light emitting device of claim 1, wherein a lateral width of the reflective layer is larger than a width between the inner edge and outer edge of the etching protective layer.