In a method of forming a silicon substrate, a gettering film is formed on a bottom surface of a silicon substrate. An oxygen ion implantation into a top surface of the silicon substrate is carried out at a substrate temperature in the range of 400.degree. C.-700.degree. C. The gettering film is removed...http://www.google.de/patents/US5970366?utm_source=gb-gplus-sharePatent US5970366 - Method of removing metallic contaminants from simox substrate
