Patent attributes
A method for manufacturing an SOI substrate is provided in which adhesiveness between a single crystal semiconductor substrate and a semiconductor substrate is improved; bonding defects are reduced; and sufficient bonding strength is provided in a bonding step and also in a process of manufacturing a semiconductor device. An insulating film including halogen is formed on a single crystal semiconductor substrate side in which an embrittlement layer is formed. The insulating film including halogen undergoes a plasma treatment. The insulating film including halogen and a face of a semiconductor substrate are bonded so as to face each other. A thermal treatment is performed to split the single crystal semiconductor substrate along the embrittlement layer, thereby separating the single crystal semiconductor substrate into a single crystal semiconductor substrate and the semiconductor substrate to which a single crystal semiconductor layer is bonded. The single crystal semiconductor layer bonded to the semiconductor substrate undergoes a planarization treatment.
