LIGHT EMITTING DEVICE AND LIGHTING INSTRUMENT INCLUDING THE SAME

• US 20120061704A1
• Filed: 08/19/2011
• Published: 03/15/2012
• Est. Priority Date: 10/11/2010
• Status: Active Grant

• Current Assignee: Suzhou Lekin Semiconductor Company Limited
• Original Assignee: LG Innotek Company Limited (LG Corporation)
• Inventors: Jeong, Hwan Hee, LEE, Sang Youl, KIM, Chung song, SONG, June O, Choi, Kwang Ki, KIM, Eun Joo, JEONG, Young kyu
• Granted Patent: US 8,552,452 B2
• Time in Patent Office: Days
• 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 33/387 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

Disclosed is a light emitting device including, a second electrode layer, a light emitting structure that includes a second conductive semiconductor layer, an active layer and a first conductive semiconductor layer and that is provided on the second electrode layer, a first electrode layer that includes a pad part and an electrode part connected to the pad part and that is provided on the light emitting structure, and a current blocking layer arranged between the second electrode layer and the light emitting structure in such a way that a part of the current block layer overlaps to correspond to the first electrode layer, wherein a width of the current blocking layer corresponding to the electrode part is different depending upon a clearance with the pad part.

Claims

1. A light emitting device, comprising:

a second electrode layer;

a light emitting structure including a second conductive semiconductor layer, an active layer and a first conductive semiconductor layer, which is provided on the second electrode layer;

a first electrode layer including a pad part and an electrode part connected to the pad part, which is provided on the light emitting structure; and

a current blocking layer arranged between the second electrode layer and the light emitting structure, wherein a part of the current block layer overlaps to correspond to the first electrode layer,

wherein a width of the current blocking layer corresponding to the electrode part is different depending upon a clearance with the pad part.

2. The light emitting device according to claim 1, wherein the width of the current blocking layer increases with decreasing distance to the pad part.

3. The light emitting device according to claim 1, wherein the electrode part includes:

an outer electrode provided at a periphery of the light emitting structure; and

at least one inner electrode arranged at inner side of the outer electrode and connected to the outer electrode,

wherein the pad part is connected to at least one of the outer electrode and the inner electrode.

4. The light emitting device according to claim 1, wherein a width of one part of the current blocking layer corresponding to a first area of the electrode part, is greater than a width of another part of the current blocking layer corresponding to a second area of the electrode part, wherein the first area is closer to the pad part than the second area.

5. The light emitting device according to claim 1, wherein a width of one part of the current blocking layer corresponding to at least one area of the electrode part increases with decreasing distance to the pad part.

6. The light emitting device according to claim 1, wherein the current blocking layer includes an overlap part and a non-overlap part corresponding to the electrode part, wherein a width of the non-overlap part of the current blocking layer is different depending upon a clearance with the pad part.

7. The light emitting device according to claim 6, wherein the width of the non-overlap part of the current blocking layer corresponding to at least one area of the electrode part increases with decreasing distance to the pad part.

8. The light emitting device according to claim 6, wherein a width of the non-overlap part of the current blocking layer corresponding to a first area of the electrode part, is greater than a width of another non-overlap part of the current blocking layer corresponding to a second area of the electrode part,

wherein the first area is closer to the pad part than the second area.

9. The light emitting device according to claim 2, wherein the width of the current blocking layer linearly increases.

10. The light emitting device according to claim 4, wherein the width of the current blocking layer corresponding to each of the first and second areas of the electrode part linearly increases.

11. The light emitting device according to claim 8, wherein the width of the non-overlap part of the current blocking layer corresponding to each of the first and second areas of the electrode part linearly increases.

12. The light emitting device according to claim 3, further comprising a passivation layer covering a lateral side and a part of the top side of the light emitting structure and contacting one side of the outer electrode,

wherein the current blocking layer includes a part extending in the other side direction of the outer electrode and non-overlapping with the outer electrode.

13. The light emitting device according to claim 12, wherein a width of the non-overlap part of the current blocking layer to the outer electrode ranges from 5 to 350% of a width of the outer electrode.

14. The light emitting device according to claim 12, wherein a width of the non-overlap part of the current blocking layer to the inner electrode ranges from 5 to 350% of a width of the inner electrode.

15. The light emitting device according to claim 12, wherein the current blocking layer includes a third part non-overlapping with the inner electrode in one side direction of the inner electrode and a fourth part non-overlapping with the inner electrode in the other side direction of the inner electrode,

wherein a width of the third part and a width of the fourth part are different.

16. The light emitting device according to claim 1, wherein the width of the electrode layer is constant.

17. The light emitting device according to claim 1, wherein the width of the current blocking layer increases stepwise.

18. A light emitting device, comprising:

a substrate;

a light emitting structure including a first conductive semiconductor layer, an active layer and a second conductive semiconductor layer, which is provided on the substrate;

a conductive layer provided on the light emitting structure;

an electrode layer including a pad part and at least one expanded electrode part extending from the pad part, which is provided on the conductive layer; and

a current blocking layer arranged between the conductive layer and the light emitting structure, wherein at least a part of the current block layer overlaps to correspond to the electrode layer,

wherein a width of the current blocking layer corresponding to the expanded electrode part is different depending upon a clearance with the pad part.

19. The light emitting device according to claim 18, wherein a width of one part of the current blocking layer corresponding to the expanded electrode part increases with decreasing distance to the pad part.

20. A lighting instrument, comprising:

a power supply connector to supply power;

a heat sink coupled to the power supply connector;

a light emitting module that includes a light emitting device mounted on a circuit board and is fixed to the heat sink; and

a reflector that is coupled to the heat sink and reflects light emitted by the light emitting module, wherein the light emitting device includes;

a second electrode layer;

a light emitting structure including a second conductive semiconductor layer, an active layer and a first conductive semiconductor layer, which is provided on the second electrode layer;

a first electrode layer including a pad part and an electrode part connected to the pad part, which is provided on the light emitting structure; and

a current blocking layer arranged between the second electrode layer and the light emitting structure, wherein a part of the current block layer overlaps to correspond to the first electrode layer,

wherein a width of the current blocking layer corresponding to the electrode part is different depending upon a clearance with the pad part.