Patent ID: 8828844

Claim:
A method for manufacturing an SOI substrate comprising the steps of: forming a first insulating layer containing silicon nitride in contact with a single crystal semiconductor substrate; forming a damaged region in the single crystal semiconductor substrate by generating plasma and by adding ion species contained in the plasma to the single crystal semiconductor substrate through the first insulating layer; forming a second insulating layer in contact with the first insulating layer after forming the damaged region; bonding a supporting substrate to the single crystal semiconductor substrate so as to face the single crystal semiconductor substrate with the first insulating layer and the second insulating layer interposed therebetween; separating a single crystal semiconductor layer from the single crystal semiconductor substrate at the damaged region and attaching the single crystal semiconductor layer to the supporting substrate by heating the single crystal semiconductor substrate; performing a dry etching on the single crystal semiconductor layer; and irradiating the single crystal semiconductor layer with a laser beam after performing the dry etching.