Light emitting device

• US 8,399,901 B2
• Filed: 01/09/2009
• Issued: 03/19/2013
• Est. Priority Date: 01/11/2008
• Status: Active Grant

• Current Assignee: Suzhou Lekin Semiconductor Company Limited
• Original Assignee: LG Innotek Company Limited (LG Corporation)
• Inventors: Bae, Duk Kyu, Cho, Hyun Kyong
• Primary Examiner(s): Luu, Chuong A
• Assistant Examiner(s): BACHNER, ROBERT G
• Application Number:
  US12/522,247
• Publication Number:
  US 20110169041A1
• Time in Patent Office: 1,530 Days
• Field of Search: 257/99, 438/125
• US Class Current: 257/99
• CPC Class Codes: H01L 2933/0025 relating to coatings
• CPC Class Codes: H01L 2933/005 relating to encapsulations
• CPC Class Codes: H01L 33/44 characterised by the coatings, e.g. passivation layer or anti-reflective coating
• CPC Class Codes: H01L 33/56 Materials, e.g. epoxy or silicone resin

Abstract

Disclosed is a light emitting device. The light emitting device comprises a light emitting semiconductor layer comprising a first conductive semiconductor layer, an active layer and a second conductive semiconductor layer, a first passivation layer on the light emitting semiconductor layer, and a second passivation layer on the first passivation layer and has an elastic modulus of 2.0 to 4.0 GPa.

Claims

1. A light emitting device, comprising:

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

an electrode layer on the first conductive semiconductor layer;

a first passivation layer on the light emitting semiconductor layer; and

a second passivation layer on the first passivation layer,

wherein the first passivation layer comprises an inorganic material,

wherein the second passivation layer comprises an organic material,

wherein the first conductive semiconductor layer has a top surface that has a downwardly-recessed groove, a plurality of protrusions being disposed on a bottom surface of the groove,

wherein the electrode layer is disposed on a bottom surface of the groove, and

wherein the electrode layer substantially has the same top surface as that of the top surface of the first conductive semiconductor layer.

2. The light emitting device as claimed in claim 1, wherein the first passivation layer has a dielectric constant of 2.0×

10<sup>−

6</sup> to 200×

10<sup>−

6</sup>.

3. The light emitting device as claimed in claim 1, wherein adhesion strength between the first passivation layer and the second passivation layer is 40 MPa to 1000 MPa.

4. The light emitting device as claimed in claim 1, further comprising a coupling metal layer and a support layer on the second passivation layer.

5. The light emitting device as claimed in claim 1, wherein the first passivation layer comprises at least one of Si, N, Ti, O, or an SOG (spin on glass).

6. The light emitting device as claimed in claim 1, wherein the first passivation layer comprises at least one of SiO₂, Si₃N₄, TiO₂, SiN, or TiN.

7. The light emitting device as claimed in claim 1, wherein the second passivation layer comprises at least one of polyimide based polymer material, acryl based polymer material or epoxy based polymer material.

15. The light emitting device as claimed in claim 1, wherein the second passivation layer has an elastic modulus of 2.0 GPa to 4.0 GPa.

16. The light emitting device as claimed in claim 1, wherein a thickness of the second passivation layer is greater than a thickness of the first passivation layer.

8. A light emitting device, comprising:

a support layer;

a first electrode layer on the support layer;

a light emitting semiconductor layer on the first electrode layer and comprising a first conductive semiconductor layer, an active layer and a second conductive semiconductor layer;

a second electrode layer on the first conductive semiconductor layer of the light emitting semiconductor layer;

a first passivation layer which surrounds the light emitting semiconductor layer and comprises an inorganic material; and

a second passivation layer which surrounds the first passivation layer and comprises an organic material,

wherein the first conductive semiconductor layer has a top surface that has a downwardly-recessed groove, a plurality of protrusions being disposed on a bottom surface of the groove,

wherein the second electrode layer is disposed on a bottom surface of the groove, and

wherein the second electrode layer substantially has the same top surface as that of the top surface of the first conductive semiconductor layer.

9. The light emitting device as claimed in claim 8, further comprising a coupling metal layer between the support layer and the first electrode layer.

10. The light emitting device as claimed in claim 8, wherein the second passivation layer has an elastic modulus of 2.0 GPa to 4.0 GPa.

11. The light emitting device as claimed in claim 8, wherein the first passivation layer has a dielectric constant of 2.0×

10<sup>−

6</sup> to 200×

10<sup>−

6</sup>.

12. The light emitting device as claimed in claim 8, wherein adhesion strength between the first passivation layer and the second passivation layer is 40 MPa to 1000 MPa.

13. The light emitting device as claimed in claim 8, wherein the first passivation layer comprises at least one of SiO₂, Si₃N₄, TiO₂, SiN, or TiN.

14. The light emitting device as claimed in claim 8, wherein the second passivation layer comprises at least one of polyimide based polymer material, acryl based polymer material or epoxy based polymer material.

17. The light emitting device as claimed in claim 8, wherein a thickness of the second passivation layer is greater than a thickness of the first passivation layer.