A damaged region is formed by generation of plasma by excitation of a source gas, and by addition of ion species contained in the plasma from one of surfaces of a single crystal semiconductor substrate; an insulating layer is formed over the other surface of the single crystal semiconductor substrate; a supporting substrate is firmly attached to the single crystal semiconductor substrate so as to face the single crystal semiconductor substrate with the insulating layer interposed therebetween; separation is performed at the damaged region into the supporting substrate to which a single crystal semiconductor layer is attached and part of the single crystal semiconductor substrate by heating of the single crystal semiconductor substrate; dry etching is performed on a surface of the single crystal semiconductor layer attached to the supporting substrate; the single crystal semiconductor layer is recrystallized by irradiation of the single crystal semiconductor layer with a laser beam to melt at least part of the single crystal semiconductor layer.