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:
Jun. 06, 2023
Filed:
Dec. 14, 2016
Wacker Chemie Ag, Munich, DE;
Harald Hertlein, Burghausen, DE;
Heinz Kraus, Zeilarn, DE;
Wacker Chemie AG, Munich, DE;
Abstract
The invention relates to a process for preparing polycrystalline silicon, comprising introducing a reaction gas containing hydrogen and silane and/or halogen silane into a reactor, wherein the reactor comprises at least one heated carrier body, on which elementary silicon has been deposited by means of pyrolysis, forming the polycrystalline silicon. In a continuous process, waste gas is led out of the reactor and hydrogen recovered from said waste gas is fed to the reactor again as circulating gas. The circulating gas has a nitrogen content of less than 1000 ppmv. The invention further relates to polycrystalline silicon having a nitrogen component of less than 2 ppba.