LIGHT EMITTING DEVICE

• US 20100230699A1
• Filed: 01/25/2010
• Published: 09/16/2010
• Est. Priority Date: 03/13/2009
• Status: Active Grant

• Current Assignee: Suzhou Lekin Semiconductor Company Limited
• Original Assignee: LG Innotek Company Limited (LG Corporation)
• Inventors: SONG, Hyun Don
• Granted Patent: US 8,193,536 B2
• Time in Patent Office: Days
• US Class Current: 257/98
• CPC Class Codes: H01L 33/387 with a plurality of electrode regions in direct contact with the semiconductor body and being electrically interconnected by another electrode layer
• CPC Class Codes: H01L 33/44 characterised by the coatings, e.g. passivation layer or anti-reflective coating

Abstract

A light emitting device including a light emitting structure having a first conductive semiconductor layer, an active layer and a second conductive semiconductor layer; a first electrode on the light emitting structure; and a photon escape layer on the light emitting structure. Further, the photon escape layer has a refractive index that is between a refractive index of the light emitting structure and a refractive index of an encapsulating material with respect to the light emitting structure such that an escape probability for photons emitted by the light emitting structure is increased.

Claims

1. A light emitting device, comprising:

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

a first electrode on the light emitting structure; and

a photon escape layer on the light emitting structure,

wherein the photon escape layer has a refractive index that is between a refractive index of the light emitting structure and a refractive index of an encapsulating material with respect to the light emitting structure such that an escape probability for photons emitted by the light emitting structure is increased.

2. The light emitting device according to claim 1, wherein the photon escape layer is formed only on an upper surface of the light emitting structure.

3. The light emitting device according to claim 1, wherein the first electrode has a wing type or a lattice pattern.

4. The light emitting device according to claim 1, wherein the photon escape layer is also on the first electrode.

5. The light emitting device according to claim 1, wherein the photon escape layer includes a dielectric film or a conductive film.

6. The light emitting device according to claim 1, wherein the photon escape layer comprises at least one of TiO₂, Al₂O₃, ZnO, MgF₂, In₂O₃, SfO₂, TiN_x, Ga₂O₃, ITO, In—

Zn—

O, and ZnO;

Al.

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

a pad on the first electrode.

8. The light emitting device according to claim 7, wherein the pad contacts the photon escape layer.

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

an insulating layer around the light emitting structure.

10. The light emitting device according to claim 9, wherein the photon escape layer is on the insulating layer.

11. A light emitting device, comprising:

a photon escape layer on a light emitting structure;

a first electrode on the light emitting structure;

a pad on the first electrode; and

a second electrode under the light emitting structure,

wherein the photon escape layer has a refractive index that is between a refractive index of the light emitting structure and a refractive index of an encapsulating material with respect to the light emitting structure such that an escape probability for photons emitted by the light emitting structure is increased.

12. The light emitting device according to claim 11, wherein the photon escape layer is formed only on an upper surface of the light emitting structure.

13. The light emitting device according to claim 11, wherein the first electrode has a wing type or a lattice pattern.

14. The light emitting device according to claim 11, wherein the photon escape layer is also on the first electrode.

15. The light emitting device according to claim 11, wherein the photon escape layer includes a dielectric film or a conductive film.

16. The light emitting device according to claim 11, wherein the photon escape layer comprises at least one of TiO₂, Al₂O₃, ZnO, MgF₂, In₂O₃, SnO₂, TiN_{x, Ga2}O₃, ITO, In—

Zn—

O, and ZnO;

Al.

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

a pad on the first electrode.

18. The light emitting device according to claim 17, wherein the pad contacts the photon escape layer.

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

an insulating layer around the light emitting structure.

20. The light emitting device according to claim 19, wherein the photon escape layer is on the insulating layer.