LIGHT EMITTING DEVICE, LIGHT EMITTING DEVICE PACKAGE

• US 20110156073A1
• Filed: 12/28/2010
• Published: 06/30/2011
• Est. Priority Date: 12/29/2009
• Status: Active Grant

• Current Assignee: Suzhou Lekin Semiconductor Company Limited
• Original Assignee: LG Innotek Company Limited (LG Corporation)
• Inventors: Choi, Woon Kyung, Park, Hyung Jo, Kim, Sun Kyung
• Granted Patent: US 9,276,175 B2
• Time in Patent Office: Days
• US Class Current: 257/98
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• 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 2924/12032 Schottky diode
• CPC Class Codes: H01L 33/44 characterised by the coatings, e.g. passivation layer or anti-reflective coating

Abstract

Provided are a light emitting device, a light emitting device package, and a lighting system. The light emitting device includes a light emitting structure, a buffer layer on the light emitting structure, and a filter layer on the buffer layer.

Claims

1. A light emitting device comprising:

a light emitting structure including a first conductive type semiconductor layer, a second conductive type semiconductor layer, and an active layer between the first conductive type semiconductor layer and the second conductive type semiconductor layer;

a buffer layer on the light emitting structure; and

a filter layer on the buffer layer,

wherein the filter layer comprises;

a first dielectric layer having a first refractive index; and

a second dielectric layer on the first dielectric layer, the second dielectric layer having a second refractive index different from the first refractive index.

2. The light emitting device according to claim 1, wherein the buffer layer comprises a hollow space part.

3. The light emitting device according to claim 2, further comprising a support layer between the filter layer and the light emitting structure.

4. The light emitting device according to claim 3, wherein the support layer comprises one of copper (Cu) and gold (Au).

5. The light emitting device according to claim 1, wherein the buffer layer comprises a material having a refractive index between a refractive index of air and a refractive index of the filter layer.

6. The light emitting device according to claim 5, wherein the buffer layer comprises at least one of spin-on-glass and MgF2.

7. The light emitting device according to claim 1, wherein a thickness of the first dielectric layer and a thickness of the second dielectric layer is λ

/(4n×

cosθ

), where λ

is a wavelength of long-wavelength light to be reflected, n is a reflective index of a dielectric layer, and θ

is an incident angle of light to a substrate.

8. The light emitting device according to claim 1, further comprising a phosphor layer on the filter layer.

9. The light emitting device according to claim 1, further comprising a passivation member at a lower periphery of the light emitting structure.

10. The light emitting device according to claim 1, further comprising:

at least one electrode on the light emitting structure; and

a conductive or non-conductive substrate under the light emitting structure.

20. A light emitting device package comprising:

a package body;

at least one electrode layer on the package body; and

a light emitting device of claim 1 electrically connected to the electrode layer.

11. A light emitting device comprising:

a light emitting structure including a first conductive type semiconductor layer, a second conductive type semiconductor layer, and an active layer between the first conductive type semiconductor layer and the second conductive type semiconductor layer;

a buffer layer on the light emitting structure; and

a filter layer on the buffer layer.

12. The light emitting device according to claim 11 wherein the buffer layer comprises an air gap or a hollow space part.

13. The light emitting device according to claim 11, wherein the buffer layer comprises a material having a refractive index between a refractive index of air and a refractive index of the filter layer.

14. The light emitting device according to claim 11, wherein the buffer layer comprises at least one of spin-on-glass and MgF₂.

15. The light emitting device according to claim 11, further comprising a pattern on the buffer layer.

16. The light emitting device according to claim 11, wherein the filter layer comprises:

a first dielectric layer having a first refractive index; and

a second dielectric layer on the first dielectric layer, the second dielectric layer having a second refractive index different from the first refractive index.

17. The light emitting device according to claim 16, wherein a thickness of the first dielectric layer and a thickness of the second dielectric layer are λ

/(4n×

cosθ

), where λ

is a wavelength of long-wavelength light to be reflected, n is a reflective index of a dielectric layer, and θ

is an incident angle of light to a substrate.

18. The light emitting device according to claim 11, further comprising a phosphor layer on the filter layer.

19. The light emitting device according to claim 11, further comprising:

at least one electrode on the light emitting structure; and

a conductive or non-conductive substrate under the light emitting structure.