Light-emitting device and method of manufacturing the same

• US 20050199885A1
• Filed: 02/17/2005
• Published: 09/15/2005
• Est. Priority Date: 03/09/2004
• Status: Active Grant

• Current Assignee: Epistar Corporation (Ennostar, Inc.)
• Original Assignee: Sanyo Electric Company Limited (Panasonic Holdings Corporation)
• Inventors: Kunisato, Tatsuya, Hata, Masayuki
• Granted Patent: US 7,968,897 B2
• Time in Patent Office: Days
• US Class Current: 257/79
• CPC Class Codes: H01L 2933/0016 relating to electrodes
• CPC Class Codes: H01L 2933/0091 Scattering means in or on the semiconductor body or semiconductor body package H01L33/22 takes precedence
• 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 33/405 Reflective materials

Abstract

A light-emitting device capable of improving light extraction efficiency is provided. This light-emitting device comprises a support substrate set on a side opposite to a light emission surface and a semiconductor element layer, bonded to the support substrate, having a side surface inclined by a prescribed angle with respect to at least the normal of the light emission surface.

Claims

1. A light-emitting device comprising:

a support substrate set on a side opposite to a light emission surface; and

a semiconductor element layer, bonded to said support substrate, having a side surface inclined by a prescribed angle with respect to at least the normal of said light emission surface.

2. The light-emitting device according to claim 1, wherein

said semiconductor element layer has a structure obtained by stacking a plurality of layers, and

the side surface of at least partial said semiconductor layer constituting said semiconductor element layer is inclined by said prescribed angle with respect to the normal of said light emission surface.

3. The light-emitting device according to claim 2, wherein

the side surfaces of all said semiconductor layers constituting said semiconductor element layer are inclined by said prescribed angle with respect to the normal of said light emission surface.

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

said light emission surface and said side surface of said semiconductor element layer form an obtuse angle.

5. The light-emitting device according to claim 1, further comprising a lateral reflecting film formed to extend along said side surface of said semiconductor element layer inclined by said prescribed angle.

6. The light-emitting device according to claim 1, further comprising a reflecting film provided at least between said support substrate and said semiconductor element layer.

7. The light-emitting device according to claim 6, wherein

a surface of said reflecting film closer to said semiconductor element layer is corrugated.

8. The light-emitting device according to claim 6, wherein

said reflecting film functions also as an electrode.

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

said light emission surface is corrugated.

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

said semiconductor element layer has a structure obtained by stacking a plurality of semiconductor layers, and

said semiconductor layer closer to said light emission side consists of an undoped semiconductor among said plurality of semiconductor layers.

11. The light-emitting device according to claim 10, wherein

said undoped semiconductor layer has an opening, and

an electrode is formed in said opening to be in contact with the surface of said semiconductor layer, other than said undoped semiconductor layer, doped with an impurity.

12. The light-emitting device according to claim 1, wherein

a single-layer film of particles is formed on a surface of said semiconductor element layer closer to said light emission side.

13. The light-emitting device according to claim 1, wherein

said support substrate includes a conductive substrate.

14. A method of manufacturing a light-emitting device, comprising steps of:

forming a semiconductor element layer having a side surface inclined by a prescribed angle with respect to at least the normal of a light emission surface on a growth substrate;

setting a support substrate on a side opposite to said light emission surface;

bonding said semiconductor element layer to said support substrate; and

removing said growth substrate.

15. The method of manufacturing a light-emitting device according to claim 14, wherein

said step of forming said semiconductor element layer includes steps of:

forming said semiconductor element layer obtained by stacking a plurality of semiconductor layers on said growth substrate;

forming a trapezoidal mask layer on the surface of said semiconductor element layer; and

forming the side surface of at least partial said semiconductor layer constituting said semiconductor element layer in a shape inclined by said prescribed angle with respect to the normal of said light emission surface by reflecting the trapezoidal shape of said mask layer by simultaneously etching said mask layer and said semiconductor element layer.

16. The method of manufacturing a light-emitting device according to claim 14, wherein

said step of bonding said semiconductor element layer to said support substrate includes a step of bonding said semiconductor element layer to said support substrate through a reflecting film.

17. The method of manufacturing a light-emitting device according to claim 16, further comprising steps of:

forming a latticed insulating film on the surface of said semiconductor element layer, and

forming said reflecting film having a corrugated surface closer to said semiconductor element layer by forming said reflecting film on said latticed insulating film to be in contact with the surface of said semiconductor element layer,

in advance of said step of bonding said semiconductor element layer to said support substrate.

18. The method of manufacturing a light-emitting device according to claim 14, wherein

said step of forming said semiconductor element layer includes steps of:

forming a latticed insulating film on said growth substrate, and

corrugating a surface of said semiconductor element layer closer to said light emission side by forming said semiconductor element layer on said latticed insulating film to fill up a region not formed with said insulating film.

19. The method of manufacturing a light-emitting device according to claim 14, wherein

said step of forming said semiconductor element layer includes steps of:

forming a single-layer film of particles on said growth substrate, and

forming said semiconductor element layer on said single-layer film of particles.

20. The method of manufacturing a light-emitting device according to claim 14, wherein

said step of forming said semiconductor element layer includes a step of forming said semiconductor element layer corresponding to a plurality of devices on said growth substrate,

said method further comprising a step of separating said semiconductor element layer into respective said devices after said step of removing said growth substrate.