Method of manufacturing SOI substrate and semiconductor device

摘要

First, a silicon germanium single-crystalline layer and a silicon single-crystalline layer are formed on a main surface of a bond wafer by epitaxy. The overall surface of the bond wafer is oxidized for forming a silicon oxide layer. Then, a base wafer is bonded to the bond wafer. The bond wafer and the base wafer bonded to each other are heated for reinforcing adhesion therebetween. Then, the bond wafer is removed by plasma etching with chlorine gas while making the silicon germanium single-crystalline layer serve as a stopper. Thereafter the silicon germanium single-crystalline layer is polished by chemical mechanical polishing to have a thickness suitable for forming a device. Thus implemented is a method of manufacturing an SOI substrate by bonding capable of employing a layer having a crystal state with small irregularity for serving as a stopper having selectivity for single-crystalline silicon and effectively using the stopper as a device forming layer.