Light emitting apparatus

• US 9,911,908 B2
• Filed: 10/08/2013
• Issued: 03/06/2018
• Est. Priority Date: 12/09/2009
• Status: Active Grant

• Current Assignee: Suzhou Lekin Semiconductor Company Limited
• Original Assignee: LG Innotek Company Limited (LG Corporation)
• Inventors: Choi, Kwang Ki, Jeong, Hwan Hee, Lee, Sang Youl, Song, June O
• Primary Examiner(s): Hsieh, Hsin-Yi
• Application Number:
  US14/049,006
• Publication Number:
  US 20140034989A1
• Time in Patent Office: 1,610 Days
• Field of Search: 257 99
• 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 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00
• CPC Class Codes: H01L 2924/12032 Schottky diode
• CPC Class Codes: H01L 33/20 with a particular shape, e.g. curved or truncated substrate
• CPC Class Codes: H01L 33/38 with a particular shape
• CPC Class Codes: H01L 33/44 characterised by the coatings, e.g. passivation layer or anti-reflective coating
• CPC Class Codes: H01L 33/58 Optical field-shaping elements
• CPC Class Codes: H01L 33/60 Reflective elements
• CPC Class Codes: H01L 33/62 Arrangements for conducting electric current to or from the semiconductor body, e.g. lead-frames, wire-bonds or solder balls

Abstract

A light emitting device including a contact layer, a blocking layer over the contact layer, a protection layer adjacent the blocking layer, a light emitter over the blocking layer, and an electrode layer coupled to the light emitter. The electrode layer overlaps the blocking layer and protection layer, and the blocking layer has an electrical conductivity that substantially blocks flow of current from the light emitter in a direction towards the contact layer. In addition, the protection layer may be conductive to allow current to flow to the light emitter or non-conductive to block current from flowing from the light emitter towards the contact layer.

Claims

1. A light emitting device comprising:

a conductive support substrate;

a metal layer including a bonding metal layer, a recess, an ohmic layer and a reflective layer, and the metal layer is provided on the conductive support substrate;

a light emitting structure layer on the metal layer and having an inclined side surface, wherein the light emitting structure layer including a first conductive semiconductor, an active layer and a second conductive semiconductor layer;

a protection layer provided on the conductive support substrate, and a portion of the protection layer is provided between the metal layer and the light emitting structure layer, wherein the ohmic layer directly contacts a side surface of the protection layer, and the reflective layer directly contacts a bottom surface of the ohmic layer;

a passivation layer on the light emitting structure layer; and

an electrode structure at least partially overlapping the protection layer and disposed on the light emitting structure layer,

wherein the electrode structure includes;

an outer electrode including a first part and a second part,

an inner electrode provided in a region between the first part and the second part of the outer electrode and extending to electrically connect the first part of the outer electrode with the second part of the outer electrode,

a pad electrically connected to at least one of the first part or the second part of the outer electrode,

wherein the outer electrode is spaced apart from an outermost side of a top of the light emitting structure layer, and wherein the outer electrode is disposed within 50 μ

m from the outermost side of the top of the light emitting structure layer,

wherein a vertical axis is defined as being perpendicular to a bottom surface of the bonding metal layer, wherein the portion of the protection layer is vertically overlapped with the passivation layer such that the portion of the protection layer and the passivation layer are aligned along the vertical axis, and

wherein the vertical axis is in a vertical direction, and wherein a portion of the bonding metal layer, a portion of the reflective layer and a portion of the ohmic layer are overlapped in the vertical direction of the vertical axis such that the portion of the reflective layer is between the portion of the ohmic layer and the portion of the bonding metal layer.

2. The light emitting device of claim 1, further comprising a current blocking layer disposed in the recess of the metal layer, and

a lateral width of the portion of the reflective layer is greater than a lateral width of the current blocking layer.

3. The light emitting device of claim 2, wherein a top surface of the current blocking layer contacts a bottom surface of the light emitting structure layer.

4. The light emitting device of claim 2, wherein a thickness of the current blocking layer is same as a depth of the recess.

5. The light emitting device of claim 1, wherein the metal layer has an uneven structure.

6. The light emitting device of claim 2, wherein the current blocking layer has a width that is about 0.9˜

1.3 times a width of the inner electrode.

7. The light emitting device of claim 2, wherein a portion of the inner electrode at least partially overlaps the current blocking layer.

8. The light emitting device of claim 1, wherein a top surface of the ohmic layer contacts a bottom surface of the second conductive semiconductor layer.

9. The light emitting device of claim 1, wherein a bottom surface of the protection layer contacts a top surface of the metal layer.

10. The light emitting device of claim 1, wherein a portion of the inner electrode at least partially overlaps the recess of the metal layer.

11. The light emitting device of claim 1, wherein the inclined side surface of the light emitting structure layer at least partially overlaps the protection layer.

12. The light emitting device of claim 1, wherein a portion of a top surface of the protection layer is exposed from the inclined side surface of the light emitting structure layer.

23. The light emitting device of claim 1, wherein a width of the first part of the outer electrode is within a range of 15 μ

m to 25 μ

m.

24. The light emitting device of claim 23, wherein a width of the second part of the outer electrode is different than the width of the first part of the outer electrode.

25. The light emitting device of claim 24, wherein the width of the second part of the outer electrode is within a range of 25 μ

m to 35 μ

m.

26. The light emitting device of claim 1, wherein a width of the outer electrode is greater than a width of the inner electrode.

29. The light emitting device of claim 1, wherein the outer electrode includes an outer side surface and an inner side surface, and the outer electrode has a width between the outer side surface and the inner side surface.

32. The light emitting device of claim 1, wherein the metal layer is vertically overlapped with the protection layer and the outer electrode.

33. The light emitting device of claim 1, wherein the electrode structure comprises at least one roughness pattern on a top surface of the electrode structure.

34. The light emitting device of claim 1, wherein the electrode structure comprises at least one roughness pattern on a bottom surface of the electrode structure.

13. A light emitting device comprising:

a conductive support substrate;

a metal layer including a recess and on the conductive support substrate, the metal layer having an uneven structure;

an ohmic layer having a top surface and a bottom surface;

a reflective layer between the metal layer and the ohmic layer;

a light emitting structure layer on the metal layer and having an inclined side surface, wherein the light emitting structure layer including a first conductive semiconductor layer, an active layer and a second conductive semiconductor layer;

a current blocking layer disposed at an area between the second conductive semiconductor layer and the recess of the metal layer;

a protection layer on the conductive support substrate, and a portion of the protection layer is provided between the metal layer and the light emitting structure layer, wherein the ohmic layer directly contacts a side surface of the protection layer, and the reflective layer directly contacts a bottom surface of the ohmic layer;

a passivation layer on the light emitting structure layer; and

an electrode structure at least partially overlapping the protection layer and disposed on the light emitting structure layer,

wherein the electrode structure includes;

an outer electrode including a first part and a second part,

an inner electrode provided in a region between the first part and the second part of the outer electrode and extending to electrically connect the first part of the outer electrode with the second part of the outer electrode,

a pad electrically connected to at least one of the first part or the second part of the outer electrode,

wherein the outer electrode is spaced apart from an outermost side of a top of the light emitting structure layer, and wherein the outer electrode is disposed within 50 μ

m from the outermost side of the top of the light emitting structure layer,

wherein a vertical axis is defined as being perpendicular to a bottom surface of the light emitting structure layer, wherein the portion of the protection layer is vertically overlapped with the passivation layer such that the portion of the protection layer and the passivation layer are aligned along the vertical axis,

wherein the vertical axis is in a vertical direction, wherein a portion of the metal layer, a portion of the reflective layer, a portion of the ohmic layer and a portion of the current blocking layer are overlapped in the vertical direction of the vertical axis such that the portion of the ohmic layer is between the portion of the current blocking layer and the portion of the reflective layer, and such that the portion of the reflective layer is between the portion of the ohmic layer and the portion of the metal layer, and

a lateral width of the portion of the reflective layer is greater than a lateral width of the current blocking layer.

14. The light emitting device of claim 13, wherein a portion of a top surface of the protection layer is exposed from the inclined side surface of the light emitting structure layer.

15. The light emitting device of claim 13, wherein a thickness of the current blocking layer is same as a depth of a recess of the ohmic layer.

16. The light emitting device of claim 13, wherein the current blocking layer has a width that is about 0.9˜

1.3 times a width of the inner electrode.

17. The light emitting device of claim 13, wherein a bottom surface of the protection layer contacts a top surface of the metal layer, and

wherein the side surface of the protection layer contacts a side surface of the ohmic layer.

27. The light emitting device of claim 13, wherein a width of the second part of the outer electrode is different than a width of the first part of the outer electrode.

28. The light emitting device of claim 13, wherein a width of the outer electrode is greater than a width of the inner electrode.

30. The light emitting device of claim 13, wherein the outer electrode includes an outer side surface and an inner side surface, and the outer electrode has a width between the outer side surface and the inner side surface.

18. A light emitting device comprising:

a conductive support substrate;

a metal layer including a recess and on the conductive support substrate, the metal layer having an uneven structure;

an ohmic layer having a top surface and a bottom surface;

a reflective layer between the metal layer and the ohmic layer;

a light emitting structure layer on the metal layer and having an inclined side surface, wherein the light emitting structure layer including a first conductive semiconductor layer, an active layer and a second conductive semiconductor layer;

a current blocking layer disposed at an area between the second conductive semiconductor layer and the recess of the metal layer;

a protection layer on the conductive support substrate, and a portion of the protection layer is provided between the metal layer and the light emitting structure layer, the inclined side surface of the light emitting structure layer at least partially overlapping the protection layer, wherein the ohmic layer directly contacts a side surface of the protection layer, and the reflective layer directly contacts a bottom surface of the ohmic layer;

a passivation layer on the light emitting structure layer; and

an electrode structure at least partially overlapping the protection layer and disposed on the light emitting structure layer,

wherein the electrode structure includes an outer electrode including a first part and a second part, an inner electrode provided in a region between the first part and the second part of the outer electrode and extending to electrically connect the first part of the outer electrode with the second part of the outer electrode, and a pad electrically connected to at least one of the first part or the second part of the outer electrode,

wherein the outer electrode is spaced apart from an outermost side of a top of the light emitting structure layer, and wherein the outer electrode is disposed within 50 μ

m from the outermost side of the top of the light emitting structure layer,

wherein a bottom surface of the protection layer contacts a top surface of the metal layer,

wherein the side surface of the protection layer contacts a side surface of the ohmic layer,

wherein the current blocking layer has a width that is about 0.9˜

1.3 times a width of the inner electrode,

wherein a vertical axis is defined as being perpendicular to a bottom surface of the light emitting structure layer, wherein the portion of the protection layer is vertically overlapped with the passivation layer such that the portion of the protection layer and the passivation layer are aligned along the vertical axis,

wherein the vertical axis is in a vertical direction, wherein a portion of the metal layer, a portion of the reflective layer, a portion of the ohmic layer and a portion of the current blocking layer are overlapped in the vertical direction of the vertical axis such that the portion of the ohmic layer is between the portion of the current blocking layer and the portion of the reflective layer, and such that the portion of the reflective layer is between the portion of the ohmic layer and the portion of the metal layer, and

a lateral width of the portion of the reflective layer is greater than a lateral width of the current blocking layer.

19. The light emitting device of claim 18, wherein a width of the first part of the outer electrode is within a range of 15 μ

m to 25 μ

m.

20. The light emitting device of claim 19, wherein a width of the second part of the outer electrode is different than the width of the first part of the outer electrode.

21. The light emitting device of claim 20, wherein the width of the second part of the outer electrode is within a range of 25 μ

m to 35 μ

m.

22. The light emitting device of claim 18, wherein a width of the outer electrode is greater than a width of the inner electrode.

31. The light emitting device of claim 18, wherein the outer electrode includes an outer side surface and an inner side surface, and the outer electrode has a width between the outer side surface and the inner side surface.