Patent ID: 7582540

Claim:
A method for manufacturing an SOI wafer, said method comprising: forming insulating films in a front surface and a mirror-polished rear surface of an active layer wafer; removing said insulating film in said front surface of said active layer wafer; after the removing, subjecting said active layer wafer to a rapid thermal annealing process in a nitridation gas atmosphere to form a vacancy layer including vacancies in a surface portion of said front surface; bonding said active layer wafer and a support wafer with said insulating film formed in said rear surface therebetween so as to form a bonded wafer, after the rapid thermal annealing process; subjecting said bonded wafer to a heat treatment for bonding enhancement in an oxidizing atmosphere which enhances a bonding strength between said active layer wafer and said support wafer and forms a denuded zone layer in said surface portion of said front surface and a BMD layer under said denuded zone layer in said active layer wafer; and thinning said active layer wafer in said bonded wafer and removing said denuded zone layer and said BMD layer so as to form an SOI layer in a surface portion of said rear surface of said active layer wafer.