Patent ID: 7795111

Claim:
A manufacturing method of an SOI substrate, comprising: preparing a base substrate and a semiconductor substrate; generating plasma by exciting a source gas and irradiating the semiconductor substrate with an ion species contained in the plasma, whereby a damaged region is formed in the semiconductor substrate; forming a bonding layer over at least one of the base substrate and the semiconductor substrate; making the base substrate and the semiconductor substrate in close contact with each other with the bonding layer interposed therebetween so that a surface of the bonding layer and a surface in contact with the bonding layer are bonded, whereby the base substrate and the semiconductor substrate are attached to each other; dividing the semiconductor substrate in the damaged region by heating, so that a semiconductor layer separated from the semiconductor substrate is formed over the base substrate; forming a gettering site layer of a semiconductor containing a Group 18 element over the semiconductor layer after dividing the semiconductor substrate in the damaged region by heating; performing a heat treatment for gettering a metal element contained in the semiconductor layer into the gettering site layer; and removing the gettering site layer and the damaged region remaining on the semiconductor layer.