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. 24, 2023
Filed:
Oct. 19, 2018
Nexwafe Gmbh, Freiburg, DE;
Kai Schillinger, Freiburg, DE;
Nena Milenkovic, Reute, DE;
NexWafe GmbH, Freiburg, DE;
Abstract
A process for removal of impurities, in particular of dopants, from chlorosilanes which includes the following steps: (a) heating a deposition surface (3); (b) contacting the heated deposition surface (3) with at least one gaseous chlorosilane mixture, the gaseous chlorosilane mixture including at least one chlorosilane and at least one impurity, in particular at least one dopant; (c) at least partially removing the impurity, in particular the dopant, by forming polycrystalline silicon depositions on the deposition surface (3), the polycrystalline silicon depositions being enriched with the impurity, in particular with the dopant; (d) discharging the purified gaseous chlorosilane mixture; (e) contacting the heated deposition surface (3) with an etching gas to return the polycrystalline silicon depositions and the impurity, in particular the dopant, into the gas phase to form a gaseous etching gas mixture; and (f) discharging the gaseous etching gas mixture.