Nitride-based light-emitting device and method of manufacturing the same

• US 20050173725A1
• Filed: 02/02/2005
• Published: 08/11/2005
• Est. Priority Date: 02/06/2004
• Status: Active Grant

• Current Assignee: Epistar Corporation
• Original Assignee: Sanyo Electric Company Limited (Panasonic Holdings Corporation)
• Inventors: Kunisato, Tatsuya, Oota, Kiyoshi, Hiroyama, Ryoji, Hata, Masayuki
• Granted Patent: US 7,592,630 B2
• Time in Patent Office: Days
• US Class Current: 257/103
• 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 33/32 containing nitrogen
• CPC Class Codes: H01L 33/38 with a particular shape
• CPC Class Codes: H01L 33/40 Materials therefor
• CPC Class Codes: H01L 33/44 characterised by the coatings, e.g. passivation layer or anti-reflective coating

Abstract

A nitride-based light-emitting device capable of suppressing reduction of the light output characteristic as well as reduction of the manufacturing yield is provided. This nitride-based light-emitting device comprises a conductive substrate at least containing a single type of metal and a single type of inorganic material having a lower linear expansion coefficient than the metal and a nitride-based semiconductor element layer bonded to the conductive substrate.

Claims

1. A nitride-based light-emitting device comprising:

a conductive substrate at least containing a single type of metal and a single type of inorganic material having a lower linear expansion coefficient than said metal; and

a nitride-based semiconductor element layer bonded to said conductive substrate.

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

said inorganic material includes a metal oxide.

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

said conductive substrate and said nitride-based semiconductor element layer are bonded to each other through at least either an electrode or a conductive material.

4. The nitride-based light-emitting device according to claim 3, wherein

said conductive substrate and said nitride-based semiconductor element layer are bonded to each other through said electrode.

5. The nitride-based light-emitting device according to claim 4, wherein

a surface of said electrode closer to said nitride-based semiconductor element layer is textured, and

said nitride-based semiconductor element layer is formed on said textured surface of said electrode.

6. The nitride-based light-emitting device according to claim 5, wherein

a surface of said conductive substrate closer to said electrode is textured, and

said electrode is bonded to said textured surface of said conductive substrate.

7. The nitride-based light-emitting device according to claim 1, further comprising a protective film covering the side surface of said nitride-based semiconductor element layer.

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

said metal includes copper.

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

said inorganic material includes copper oxide.

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

said metal includes copper, and

said inorganic material includes copper oxide.

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

said conductive substrate has thermal conductivity of at least about 100 W/mK.

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

said conductive substrate has a Young'"'"'s modulus of not more than about 120 GPa.

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

said conductive substrate has a linear expansion coefficient of not more than about 18×

10<sup>−

6</sup>/K.

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

growing a nitride-based semiconductor element layer on a growth substrate;

bonding a conductive substrate at least containing a single type of metal and a single type of inorganic material having a lower linear expansion coefficient than said metal to said nitride-based semiconductor element layer; and

removing said growth substrate from said nitride-based semiconductor element layer to which said conductive substrate is bonded.

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

said inorganic material includes a metal oxide.

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

said step of bonding said conductive substrate to said nitride-based semiconductor element layer includes a step of bonding said conductive substrate to said nitride-based semiconductor element layer through at least either an electrode or a conductive material.

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

said step of bonding said conductive substrate to said nitride-based semiconductor element layer includes a step of bonding said conductive substrate to said nitride-based semiconductor element layer through said electrode.

18. The method of manufacturing a nitride-based light-emitting device according to claim 17, wherein

said step of bonding said conductive substrate to said nitride-based semiconductor element layer through said electrode includes steps of:

texturing a surface of said nitride-based semiconductor element layer,

forming said electrode on said textured surface of said nitride-based semiconductor element layer, and

bonding said conductive substrate to a surface of said electrode opposite to said nitride-based semiconductor element layer.

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

said step of forming said electrode on said textured surface of said nitride-based semiconductor element layer includes a step of forming said electrode on said textured surface of said nitride-based semiconductor element layer to have a textured surface reflecting said texture on said surface of said nitride-based semiconductor element, and

said step of bonding said conductive substrate to said surface of said electrode opposite to said nitride-based semiconductor element layer includes steps of:

texturing a surface of said conductive substrate, and

bonding said conductive substrate to said surface of said electrode opposite to said nitride-based semiconductor element layer so that the positions of projecting and recess portions of said electrode and the positions of recess and projecting portions of said conductive substrate coincide with each other.

20. The method of manufacturing a nitride-based light-emitting device according to claim 14, further comprising a step of forming a protective film to cover the side surface of said nitride-based semiconductor element layer in advance of said step of bonding said conductive substrate to said nitride-based semiconductor element layer.