Patent · US Active

Method for manufacturing soi wafer

US7985660B2 · kind B2 · utility

0Cited by
2References
14Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 16, 2008
Grant dateJul 26, 2011
Priority date
Expiry dateApr 16, 2028

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01L21/76256
  • WIPO fieldSemiconductors
  • WIPO sectorElectrical engineering

Abstract

The present invention provides a method for manufacturing an SOI wafer, including: a step of preparing a base wafer consisting of a p+ silicon single crystal wafer and a bond wafer consisting of a silicon single crystal wafer containing a dopant at a lower concentration than that in the base wafer; a step of forming a silicon oxide film on an entire surface of the base wafer based on thermal oxidation; a step of bonding the bond wafer to the base wafer through the silicon oxide film; and a step of reducing a thickness of the bond wafer to form an SOI layer, wherein a step of forming a CVD insulator film on a surface on an opposite side of a bonding surface of the base wafer is provided before the thermal oxidation step for the base wafer. As a result, it is possible to provide the method for manufacturing an SOI wafer which can easily prevent the p-type dopant contained in the base wafer from outwardly diffusing from the surface on the opposite side of the bonding surface of the base wafer due to a high-temperature heat treatment, suppress this dopant from being mixed into the SOI layer, and reduce warpage.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.