Wafer temporary bonding method using silicon direct bonding

• US 8,343,851 B2
• Filed: 09/17/2009
• Issued: 01/01/2013
• Est. Priority Date: 09/18/2008
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Kim, Jung-ho, Bae, Dae-lok, Lee, Jong-wook, Choi, Seung-woo, Kang, Pil-kyu
• Primary Examiner(s): WILCZEWSKI, MARY A
• Application Number:
  US12/585,537
• Publication Number:
  US 20100068868A1
• Time in Patent Office: 1,202 Days
• Field of Search: 438/455, 438/459, 438/458, 257/E21.088
• US Class Current: 438/458
• CPC Class Codes: H01L 21/6835 using temporarily an auxiliary support
• CPC Class Codes: H01L 2221/6835 used as a support during build up manufacturing of active devices
• CPC Class Codes: H01L 2221/68359 used as a support during manufacture of interconnect decals or build up layers
• CPC Class Codes: H01L 2224/83 using a layer connector
• CPC Class Codes: H01L 24/83 using a layer connector
• CPC Class Codes: H01L 24/94 at wafer-level, i.e. with connecting carried out on a wafer comprising a plurality of undiced individual devices
• CPC Class Codes: H01L 25/50 Multistep manufacturing processes of assemblies consisting of devices, each device being of a type provided for in group H01L27/00 or H01L29/00 H01L21/50 takes precedence
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/01005 Boron [B]
• CPC Class Codes: H01L 2924/01006 Carbon [C]
• CPC Class Codes: H01L 2924/01021 Scandium [Sc]
• CPC Class Codes: H01L 2924/01033 Arsenic [As]
• CPC Class Codes: H01L 2924/01047 Silver [Ag]
• CPC Class Codes: H01L 2924/10253 Silicon [Si]

Abstract

A wafer temporary bonding method using silicon direct bonding (SDB) may include preparing a carrier wafer and a device wafer, adjusting roughness of a surface of the carrier wafer, and combining the carrier wafer and the device wafer using the SDB. Because the method uses SDB, instead of an adhesive layer, for a temporary bonding process, a module or process to generate and remove an adhesive is unnecessary. Also, a defect in a subsequent process, for example, a back-grinding process, due to irregularity of the adhesive may be prevented.

Claims

1. A wafer temporary bonding method using silicon direct bonding (SDB), the method comprising:

preparing a carrier wafer and a device wafer;

adjusting a roughness of a surface of the carrier wafer;

combining the carrier wafer and the device wafer using SDB;

back-grinding the device wafer; and

separating the carrier wafer from the device wafer in a separation process.

2. The method of claim 1, wherein the roughness of the surface of the carrier wafer is adjusted to have a bonding strength sufficient to sustain the device wafer in a subsequent process and to allow separation from the device wafer in the separation process.

3. The method of claim 2, wherein the subsequent process is a back-grinding process.

4. The method of claim 2, wherein the separation process includes using at least one of a blade and a separation solvent.

5. The method of claim 1, wherein adjusting the roughness of the surface of the carrier wafer includes performing at least one of plasma processing, wet etching, cleaning, and thin film deposition.

6. The method of claim 1, wherein combining the carrier wafer and the device wafer using SDB includes

cleaning the device wafer by dipping the device wafer in deionized water;

mounting the carrier wafer on the device wafer; and

annealing the carrier wafer and device wafer.

7. The method of claim 1, further comprising:

combining at least another device wafer to the device wafer.

8. The method of claim 1, further comprising:

adjusting a roughness of a surface of the device wafer.

9. The method of claim 1, wherein the separation process includes using at least one of a blade and separation solvent.

10. The method of claim 9, wherein the roughness of the surface of the carrier wafer and a roughness of a surface of the device wafer are adjusted so that a bonding strength between the carrier wafer and the device wafer is sufficient to sustain the device wafer in a back-grinding process and is sufficient to allow separation of the carrier wafer from the device wafer in the separation process.

11. A method of fabricating a semiconductor device, the method comprising:

bonding a carrier wafer and a device wafer using SDB (silicon direct bonding);

back-grinding the device wafer; and

separating the carrier wafer from the device wafer in a separation process.

12. The method of claim 11, wherein bonding the carrier wafer and the device wafer includes

preparing the carrier wafer and the device wafer,

adjusting a roughness of a surface of the carrier wafer, and

combining the carrier wafer and the device wafer using SDB.

13. The method of claim 12, wherein adjusting the roughness of the surface of the carrier wafer includes performing at least one of plasma processing, wet etching, cleaning, and thin film deposition.

14. The method of claim 12, further comprising:

adjusting a roughness of a surface of the device wafer using at least one of plasma processing, wet etching, cleaning, and thin film deposition.

15. The method of claim 12, wherein combining the carrier wafer and the device wafer using SDB includes

cleaning the device wafer by dipping the device wafer in deionized water;

mounting the carrier wafer on the device wafer; and

annealing the carrier wafer and device wafer.

16. The method of claim 12, wherein the roughness of the surface of the carrier wafer and a roughness of a surface of the device wafer are adjusted so that a bonding strength between the carrier wafer and the device wafer is sufficient to sustain the device wafer in a back-grinding process and is sufficient to allow separation of the carrier wafer from the device wafer in the separation process.