Light emitting device including a plurality of GaN-based reflective layers

• US 8,390,006 B2
• Filed: 11/17/2010
• Issued: 03/05/2013
• Est. Priority Date: 01/29/2010
• Status: Active Grant

• Current Assignee: Suzhou Lekin Semiconductor Company Limited
• Original Assignee: LG Innotek Company Limited (LG Corporation)
• Inventors: Kang, Dae Sung, Jung, Myung Hoon
• Primary Examiner(s): PARENDO, KEVIN A
• Application Number:
  US12/948,423
• Publication Number:
  US 20110186882A1
• Time in Patent Office: 839 Days
• Field of Search: 257/94, 257 96- 98, 257/103, 257/E33.025, 257/E33.049, 257/E33.072, 438/46, 438/47
• US Class Current: 257/94
• 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 2933/0083 Periodic patterns for optical field-shaping in or on the semiconductor body or semiconductor body package, e.g. photonic bandgap structures
• CPC Class Codes: H01L 33/10 with a light reflecting structure, e.g. semiconductor Bragg reflector

Abstract

Provided are a light emitting device, a method of manufacturing the light emitting device, a light emitting device package, and a lighting system. The light emitting device includes a reflective layer including a first GaN-based semiconductor layer having a first refractive index, a second GaN-based semiconductor layer having a second refractive index less than the first refractive index, and a third GaN-based semiconductor layer having a third refractive index less than the second refractive index and a light emitting structure layer including a first conductive type semiconductor layer, a second conductive type semiconductor layer, and an active layer disposed between the first conductive type semiconductor layer and the second conductive type semiconductor layer on the reflective layer.

Claims

1. A light emitting device, comprising:

a reflective layer comprising a first GaN-based semiconductor layer having a first refractive index, a second GaN-based semiconductor layer having a second refractive index less than the first refractive index, and a third GaN-based semiconductor layer having a third refractive index less than the second refractive index; and

a light emitting structure layer comprising a first conductive type semiconductor layer, a second conductive type semiconductor layer, and an active layer disposed between the first conductive type semiconductor layer and the second conductive type semiconductor layer on the reflective layer,

wherein the first GaN-based semiconductor layer and the second GaN-based semiconductor layer are alternately stacked in a vertical direction in a first region of the reflective layer, and the second GaN-based semiconductor layer and the third GaN-based semiconductor layer are alternately stacked in the vertical direction in a second region of the reflective layer,

wherein the reflective layer comprises a plurality of layers including at least two layers from the first GaN-based semiconductor layer, the second GaN-based semiconductor layer and the third GaN-based semiconductor layer, and

wherein at least two of the first GaN-based semiconductor layer, the second GaN-based semiconductor layer, and the third GaN-based semiconductor layer are alternately disposed in a horizontal direction perpendicular to the vertical direction.

2. The light emitting device of claim 1, wherein the first GaN-based semiconductor layer and the third GaN-based semiconductor layer are alternately disposed in the horizontal direction in a third region of the reflective layer, and the second GaN-based semiconductor layer is disposed in a fourth region of the reflective layer.

3. The light emitting device of claim 2, wherein the first GaN-based semiconductor layer and the third GaN-based semiconductor layer are disposed along the horizontal direction in a lattice shape.

4. The light emitting device of claim 2, wherein the first GaN-based semiconductor layer and the third GaN-based semiconductor layer are disposed along the horizontal direction in a strip shape.

5. The light emitting device of claim 1, wherein the first GaN-based semiconductor layer and the second GaN-based semiconductor layer are alternately disposed in the horizontal direction in a third region of the reflective layer, and the second GaN-based semiconductor layer and the third GaN-based semiconductor layer are alternately disposed horizontally in a fourth region of the reflective layer.

6. The light emitting device of claim 5, wherein the first GaN-based semiconductor layer and the second GaN-based semiconductor layer are horizontally disposed in a lattice shape, and the second GaN-based semiconductor layer and the third GaN-based semiconductor layer are horizontally disposed in the lattice shape.

7. The light emitting device of claim 5, wherein the first GaN-based semiconductor layer and the second GaN-based semiconductor layer are horizontally disposed in a strip shape, and the second GaN-based semiconductor layer and the third GaN-based semiconductor layer are horizontally disposed in the strip shape.

8. The light emitting device of claim 1, wherein the first GaN-based semiconductor layer comprises an InGaN layer, the second GaN-based semiconductor layer comprises a GaN layer, and the third GaN-based semiconductor layer comprises an AlGaN layer.

9. The light emitting device of claim 1, further comprising a nitride semiconductor layer and a substrate, which are disposed under the reflective layer.

10. The light emitting device of claim 1, further comprising a first electrode layer on the first conductive type semiconductor layer and a second electrode layer on the second conductive type semiconductor layer.

11. The light emitting device of claim 1, wherein each of the first GaN-based semiconductor layer, the second GaN-based semiconductor layer, and the third GaN-based semiconductor layer has a thickness of about 40 nm to about 60 nm.

12. The light emitting device of claim 1, wherein each of the first GaN-based semiconductor layer, the second GaN-based semiconductor layer, and the third GaN-based semiconductor layer has a width of about 40 nm to about 50 μ

m.

13. A light emitting device, comprising:

a reflective layer comprising a first GaN-based semiconductor layer having a first refractive index, a second GaN-based semiconductor layer having a second refractive index less than the first refractive index, and a third GaN-based semiconductor layer having a third refractive index less than the second refractive index; and

a light emitting structure layer comprising a first conductive type semiconductor layer, a second conductive type semiconductor layer, and an active layer disposed between the first conductive type semiconductor layer and the second conductive type semiconductor layer on the reflective layer,

wherein the first conductive type semiconductor layer, the active layer, and the second conductive type semiconductor layer are stacked in a vertical direction, and

wherein the first GaN-based semiconductor layer and the second GaN-based semiconductor layer are alternately disposed in a horizontal direction perpendicular to the vertical direction in a third region of the reflective layer, and the second GaN-based semiconductor layer and the third GaN-based semiconductor layer are alternately disposed in the horizontal direction perpendicular to the vertical direction in a fourth region of the reflective layer.

14. The light emitting device of claim 13, wherein the first GaN-based semiconductor layer and the second GaN-based semiconductor layer are disposed along the horizontal direction in a lattice shape, and the second GaN-based semiconductor layer and the third GaN-based semiconductor layer are disposed along the horizontal direction in the lattice shape.

15. The light emitting device of claim 13, wherein the first GaN-based semiconductor layer comprises an InGaN layer, the second GaN-based semiconductor layer comprises a GaN layer, and the third GaN-based semiconductor layer comprises an AlGaN layer.

16. The light emitting device of claim 13, further comprising a nitride semiconductor layer and a substrate, which are disposed under the reflective layer.

17. The light emitting device of claim 13, further comprising a first electrode layer on the first conductive type semiconductor layer and a second electrode layer on the second conductive type semiconductor layer.

18. The light emitting device of claim 13,

wherein each of the first GaN-based semiconductor layer, the second GaN-based semiconductor layer, and the third GaN-based semiconductor layer has a thickness of about 40 nm to about 60 nm, and

wherein each of the first GaN-based semiconductor layer, the second GaN-based semiconductor layer, and the third GaN-based semiconductor layer has a width of about 40 nm to about 50 gm.

19. A light emitting device, comprising:

a reflective layer comprising a first GaN-based semiconductor layer having a first refractive index, a second GaN-based semiconductor layer having a second refractive index less than the first refractive index, and a third GaN-based semiconductor layer having a third refractive index less than the second refractive index; and

a light emitting structure layer comprising a first conductive type semiconductor layer, a second conductive type semiconductor layer, and an active layer disposed between the first conductive type semiconductor layer and the second conductive type semiconductor layer on the reflective layer,

wherein the first GaN-based semiconductor layer and the second GaN-based semiconductor layer are alternately stacked in a vertical direction in a first region of the reflective layer, and the second GaN-based semiconductor layer and the third GaN-based semiconductor layer are alternately stacked in the vertical direction in a second region of the reflective layer, and

wherein the first GaN-based semiconductor layer and the second GaN-based semiconductor layer are alternately disposed in a horizontal direction in a third region of the reflective layer, and the second GaN-based semiconductor layer and the third GaN-based semiconductor layer are alternately disposed horizontally in a fourth region of the reflective layer.

20. The light emitting device of claim 19, wherein the first GaN-based semiconductor layer and the second GaN-based semiconductor layer are horizontally disposed in a lattice shape, and the second GaN-based semiconductor layer and the third GaN-based semiconductor layer are horizontally disposed in the lattice shape.