FABRICATION METHOD OF NITRIDE-BASED SEMICONDUCTOR DEVICE

• US 20080182384A1
• Filed: 10/30/2007
• Published: 07/31/2008
• Est. Priority Date: 11/01/2006
• Status: Active Grant

• Current Assignee: Sharp Fukuyama Laser Co., Ltd. (Hon Hai Precision Industry Co., Ltd.)
• Original Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Inventors: Hata, Toshio
• Granted Patent: US 7,892,873 B2
• Time in Patent Office: Days
• US Class Current: 438/458
• CPC Class Codes: H01L 33/0093 Wafer bonding; Removal of the growth substrate

Abstract

A fabrication method of a nitride-based semiconductor device includes the steps of forming a stacked structure constituted of a nitride-based semiconductor on a support substrate, depositing a first bonding metal on the stacked structure, depositing a second bonding metal on a retention substrate, bonding the first bonding metal and the second bonding metal in a state where the first bonding metal and the second bonding metal face each other to unite the retention substrate and the stacked structure, wherein the first bonding metal and the second bonding metal constitute the bonding metal, and separating the support substrate from the stacked structure for removal. The area of the surface of the retention substrate is set smaller than the area of the surface of the support substrate. Accordingly, cracking, fracture, chipping, and the like at the retention substrate can be prevented.

Claims

1. A fabrication method of a nitride-based semiconductor device including a structure in which a retention substrate and a stacked structure constituted of a nitride-based semiconductor are united with a bonding metal therebetween, said fabrication method comprising the steps of:

forming said stacked structure constituted of said nitride-based semiconductor on a support substrate,

depositing a first bonding metal on said stacked structure,

depositing a second bonding metal on said retention substrate,

bonding said first bonding metal to said second bonding metal in a state where said first bonding metal and said second bonding metal face each other to unite said retention substrate and said stacked structure, said first bonding metal and said second bonding metal constituting said bonding metal, and

separating said support substrate from said stacked structure for removal,

wherein an area of a surface of said retention substrate corresponding to the second bonding metal deposition side is set smaller than the area of the surface of said support substrate corresponding to the stacked structure formation side.

2. The fabrication method of a nitride-based semiconductor device according to claim 1, wherein said bonding metal is made to avoid contact with said support substrate.

3. The fabrication method of a nitride-based semiconductor device according to claim 1, wherein said support substrate has a thickness of not more than 400 μ

m.

4. The fabrication method of a nitride-based semiconductor device according to claim 1, wherein said retention substrate is united with said stacked structure along an entire area of said surface corresponding to said second bonding metal deposition side in said step of bonding.

5. The fabrication method of a nitride-based semiconductor device according to claim 1, wherein removal of said support substrate in said step of removing the support substrate is effected by applying a laser beam from a backside of said support substrate for separation of said stacked structure and said support substrate.

6. The fabrication method of a nitride-based semiconductor device according to claim 5, said method further comprising the step of mirror-polishing a face of said support substrate to which said laser beam is to be applied, prior to said step of removing the support substrate.

7. The fabrication method of a nitride-based semiconductor device according to claim 5, wherein said laser beam is applied with said backside of said support substrate located at a lower side.

8. The fabrication method of a nitride-based semiconductor device according to claim 1, wherein said retention substrate is formed of at least one member selected from the group consisting of P-doped or N-doped Si, Ge, Sic and GaP.