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:
Jan. 09, 1990
Filed:
Jan. 03, 1989
Helene Prigge, Unterschleissheim, DE;
Robert Rurlander, Halsbach, DE;
Michael Schwab, Neuotting, DE;
Hans P Bortner, Burghausen, DE;
Andreas Englmuller, Burghausen, DE;
Wacker-Chemitronic Gesellschaft fur Elektronik-Grundstoffe mbH, Burghausen, DE;
Abstract
The liquid or gaseous substances, such as hydrogen or trichlorosilane, enntered in the gas-phase deposition of silicon may contain n-type doping impurities which can be removed by adduct formation with silicon, titanium or tin halides. The impurities can be liberated from the adducts by thermal treatment and finally removed. The halides left behind are capable of again forming adducts and are again used to remove the impurities. The process can consequently be operated cyclically and is remarkable for the low quantity of chemicals required and for its ecological harmlessness.