Patent ID: 7977209

Claim:
A method for manufacturing an SOI substrate, comprising: (1) forming a hydrogen ion-implanted layer on the surface side of a first substrate which is a single-crystal silicon substrate; (2) applying a surface activation treatment to at least one of the surface of a second substrate which is a transparent insulating substrate and the surface of said first substrate; (3) bonding together the surface of said first substrate and the surface of said second substrate; and (4) forming an SOI layer on the surface of said second substrate by closely adhering the rear surface of said first substrate of said bonded substrates on a heating plate kept at a temperature of 200° C. or higher but not higher than 350° C. to heat said first substrate and thereby peel off a silicon layer from said first substrate, wherein (3) includes a sub-step of heat-treating said first substrate and said second substrate at 100 to 350° C. after said bonding, with said first and second substrates bonded together.