Continuous process for refining silicon

US4900532A · kind A · utility

Assignee

• BAYER HEALTHCARE LLC · DE

Inventors

• Gunter Kurz · Goldkronach, DE
• Ingo Schwirtlich · Miltenberg, DE
• Klaus Gebauer · Krefeld, DE

Key dates

• Filing date: Aug 9, 1988
• Grant date: Feb 13, 1990
• Expiry date: Aug 9, 2008

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C01B33/037
• WIPO field: Materials, metallurgy
• WIPO sector: Chemistry

Abstract

An improved process for purifying and refining silicon containing impurities comprises: PA1 (i) continuously melting impure silicon to form a thin film silicon melt, preferably on an inclined surface of a silicon-resistant material, PA1 (ii) continuously treating the thin film silicon melt with a reactive gas with or without an inert gas, PA1 (iii) optionally degassing the treated silicon melt, and thereafter PA1 (iv) continuously crystallizing the treated silicon.