Method for producing silicon film-transferred insulator wafer

A method for producing a silicon film-transferred insulator wafer, the method comprising:

• a surface activation step of performing a surface activation treatment on at least one of a surface of an insulator wafer and a hydrogen ion-implanted surface of a single crystal silicon wafer into which a hydrogen ion has been implanted to form a hydrogen ion-implanted layer;
• a bonding step of bonding the hydrogen ion-implanted surface to the surface of the insulator wafer to obtain bonded wafers;
• a first heating step of heating the bonded wafers at a first temperature;
• a grinding and/or etching step of grinding and/or etching a surface of a single crystal silicon wafer side of the bonded wafers thus heated so as to thin the single crystal silicon wafer of the bonded wafers;
• a second heating step of heating the bonded wafers thus ground and/or etched at a second temperature which is higher than the first temperature;
• and
• a detachment step of performing detachment at the hydrogen ion-implanted layer by applying a mechanical impact to the hydrogen ion-implanted layer of the bonded wafers thus heated at the second temperature,
• wherein after said grinding and/or etching step and before said second heating step, a mirror finish step of polishing the ground and/or etched surface of the single crystal silicon wafer side of the bonded wafers into a mirror surface.