The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 03, 2005
Filed:
Nov. 21, 2001
Hans-dieter Block, Leverkusen, DE;
Leslaw Mleczko, Bochum, DE;
Hans-joachim Leimkühler, Leverkusen, DE;
Rainer Weber, Odenthal, DE;
Knud Werner, Krefeld, DE;
Dietmar Schwanke, Monheim, DE;
Johannes-peter Schäfer, Kürten, DE;
Gebhard Wagner, Odenthal, DE;
Hans-Dieter Block, Leverkusen, DE;
Leslaw Mleczko, Bochum, DE;
Hans-Joachim Leimkühler, Leverkusen, DE;
Rainer Weber, Odenthal, DE;
Knud Werner, Krefeld, DE;
Dietmar Schwanke, Monheim, DE;
Johannes-Peter Schäfer, Kürten, DE;
Gebhard Wagner, Odenthal, DE;
SolarWorld AG, Bonn, DE;
Abstract
The invention relates to a method for the production of high purity silicon, characterized by the following steps: a) reaction of metallic silicon with silicon tetrachloride (SiCl), hydrogen (H) and hydrochloric acid (HCl) at a temperature of 500 to 800° C. and a pressure of 25 to 40 bar to give a trichlorosilane-containing (SiHCl) feed gas stream, b) removal of impurities from the resultant trichlorosilane-containing feed gas stream by scrubbing with condensed chlorosilanes at a pressure of 25 to 40 bar and a temperature of 160 to 200° C. in a multi-stage distillation column, to give a purified trichlorosilane-containing feed gas stream and a solid-containing chlorosilane suspension and a distillative separation of the purified feed gas stream into a partial stream essentially comprising SiCland a partial stream, essentially comprising SiHCl, c) disproportionation of the SiHCl-containing partial stream to give SiCland SiH, whereby the disproportionation is carried out in several reactive/distillative reaction zones, with a counter-current of vapour and liquid, on catalytic solids at a pressure of 500 mbar to 50 bar and SiHClis introduced into a first reaction zone, the lower boiling SiH-containing disproportionation product produced there undergoes an intermediate condensation in a temperature range of −25° C. to 50° C., the non-condensing SiH-containing product mixture is fed to one or more further reactive/distillative reaction zones and the lower boiling product thus generated, containing a high proportion of SiHis completely or partially condensed in the head condenser and d) thermal decomposition of the SiHto give high purity silicon.