Method of producing silicon thin film, method of constructing SOI substrate and semiconductor device

Abstract

To decrease the thickness of a silicon thin film to a desired value without deterioration of the quality thereof while avoiding the surface roughness due to speed increasing oxidation of crystal defect portions occurring when conducting the conventional sacrificial oxidation, effect of dust particles, etc. and also avoiding deterioration of high pressure resistance of the oxide film associated with the surface roughness. A silicon ultrathin film SOI layer is produced in the following two steps: preparing a SOI wafer having a silicon thin film, which exhibits less precipitation of oxygen, thereon by the SIMOX method or the semiconductor bonding method, and cleaning the SOI wafer with an alkali solution such as SC1 and TMAH, so as to utilize the etching action of the aqueous cleaner.

Dependencies are inferred from the claim text.