Nitride semiconductor light emitting device and method of manufacturing the same

• US 20100032701A1
• Filed: 08/04/2009
• Published: 02/11/2010
• Est. Priority Date: 08/05/2008
• Status: Active Grant

• Current Assignee: Xiamen San'An Optoelectronics Co.Ltd. (Sanan Optoelectronics Company Limited)
• Original Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Inventors: Fudeta, Mayuko
• Granted Patent: US 8,063,410 B2
• Time in Patent Office: Days
• US Class Current: 257/98
• CPC Class Codes: H01L 2933/0016 relating to electrodes
• CPC Class Codes: H01L 33/0093 Wafer bonding; Removal of the growth substrate
• CPC Class Codes: H01L 33/145 with a current-blocking structure
• CPC Class Codes: H01L 33/22 Roughened surfaces, e.g. at the interface between epitaxial layers
• 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 33/42 Transparent materials
• CPC Class Codes: H01L 33/46 Reflective coating, e.g. dielectric Bragg reflector

Abstract

A nitride semiconductor light-emitting device including a reflecting layer made of a dielectric material, a transparent conductive layer, a p-type nitride semiconductor layer, a light emitting layer and an n-type nitride semiconductor layer in this order and a method of manufacturing the same are provided. The transparent conductive layer is preferably made of a conductive metal oxide or an n-type nitride semiconductor, and the reflecting layer made of a dielectric material preferably has a multilayer structure obtained by alternately stacking a layer made of a dielectric material having a high refractive index and a layer made of a dielectric material having a low refractive index.

Claims

1. A nitride semiconductor light-emitting device including a reflecting layer made of a dielectric material, a transparent conductive layer, a p-type nitride semiconductor layer, a light emitting layer and an n-type nitride semiconductor layer in this order.

2. The nitride semiconductor light-emitting device according to claim 1, including a support substrate, said reflecting layer made of a dielectric material, said transparent conductive layer, said p-type nitride semiconductor layer, said light emitting layer and said n-type nitride semiconductor layer in this order.

3. The nitride semiconductor light-emitting device according to claim 1, wherein

said transparent conductive layer is made of a conductive metal oxide.

4. The nitride semiconductor light-emitting device according to claim 1, wherein

said transparent conductive layer is made of an n-type nitride semiconductor.

5. The nitride semiconductor light-emitting device according to claim 1, wherein

said reflecting layer made of a dielectric material has a multilayer structure obtained by alternately stacking a layer made of a dielectric material having a high refractive index and a layer made of a dielectric material having a low refractive index.

6. The nitride semiconductor light-emitting device according to claim 1, wherein

said reflecting layer made of a dielectric material has reflectance of 80 to 100% with respect to light emitted from said light emitting layer.

7. The nitride semiconductor light-emitting device according to claim 1, wherein

the surface on the side provided with said reflecting layer made of a dielectric material is planar in the surfaces of a nitride semiconductor layer consisting of said p-type nitride semiconductor layer, said light emitting layer and said n-type nitride semiconductor layer.

8. The nitride semiconductor light-emitting device according to claim 1, wherein

the surface opposite to the side provided with said reflecting layer made of a dielectric material is irregularized in the surfaces of a nitride semiconductor layer consisting of said p-type nitride semiconductor layer, said light emitting layer and said n-type nitride semiconductor layer.

9. The nitride semiconductor light-emitting device according to claim 1, wherein

the length of said transparent conductive layer in a direction perpendicular to the thickness direction is smaller than the length of said p-type nitride semiconductor layer in a direction perpendicular to the thickness direction, and

said reflecting layer made of a dielectric material is in contact with both side surfaces of said transparent conductive layer and a surface of said transparent conductive layer closer to said reflecting layer made of a dielectric material and further in contact with a part of a surface of said p-type nitride semiconductor layer closer to said transparent conductive layer, said part of a surface being not in contact with said transparent conductive layer.

10. The nitride semiconductor light-emitting device according to claim 1, wherein

said reflecting layer made of a dielectric material has a through-port passing through said reflecting layer in the thickness direction in a region located immediately under said transparent conductive layer.

11. The nitride semiconductor light-emitting device according to claim 1, wherein

said p-type nitride semiconductor layer includes a current blocking region formed in contact with said transparent conductive layer.

12. The nitride semiconductor light-emitting device according to claim 11, wherein

said reflecting layer made of a dielectric material has a through-port passing through said reflecting layer in the thickness direction in a region located immediately under said transparent conductive layer, and

said through-port provided in said reflecting layer made of a dielectric material is positioned immediately under said current blocking region.

13. The nitride semiconductor light-emitting device according to claim 2, further including a eutectic bonding layer having a single- or multilayer structure made of a metal including a eutectic bonding metal or an alloy containing said metal between said support substrate and said reflecting layer made of a dielectric material.

14. The nitride semiconductor light-emitting device according to claim 13, further including an adhesion layer between said reflecting layer made of a dielectric material and said eutectic bonding layer.

15. The nitride semiconductor light-emitting device according to claim 2, wherein

said support substrate is a substrate made of a plated metal or alloy.

16. The nitride semiconductor light-emitting device according to claim 1, wherein

the thickness of said reflecting layer made of a dielectric material is 0.2 to 5 μ

m.

17. A method of manufacturing a nitride semiconductor light-emitting device including a support substrate, a reflecting layer made of a dielectric material, a transparent conductive layer, a p-type nitride semiconductor layer, a light emitting layer and an n-type nitride semiconductor layer in this order, including the steps of:

(A) stacking said n-type nitride semiconductor layer, said light emitting layer and said p-type nitride semiconductor layer on a growth substrate in this order;

(B) forming said transparent conductive layer on the surface of said p-type nitride semiconductor layer;

(C) forming said reflecting layer made of a dielectric material on an exposed surface of an obtained laminate;

(D) stacking said support substrate;

(E) removing said growth substrate; and

(F) obtaining a plurality of nitride semiconductor light-emitting devices by performing chip division.

18. The method of manufacturing a nitride semiconductor light-emitting device according to claim 17, further comprising a step (G) of partially exposing said transparent conductive layer by forming a through-port passing through said reflecting layer in the thickness direction in said reflecting layer made of a dielectric material after the step (C).

19. The method of manufacturing a nitride semiconductor light-emitting device according to claim 18, wherein

said through-port is formed by etching and said transparent conductive layer functions as an etching stopper layer in the step (G).

20. The method of manufacturing a nitride semiconductor light-emitting device according to claim 17, further comprising a step (H) of exposing said reflecting layer made of a dielectric material by forming recesses substantially at a constant interval from the side of said n-type nitride semiconductor layer between the steps (E) and (F).

21. The method of manufacturing a nitride semiconductor light-emitting device according to claim 17, further comprising a step (I) of irregularizing the surface of said n-type nitride semiconductor layer after the step (E).

22. The method of manufacturing a nitride semiconductor light-emitting device according to claim 20, wherein

said chip division is performed on any positions on the bottom surfaces of said recesses in the step (F).