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:
Sep. 13, 2022
Filed:
Jul. 31, 2018
Applicant:
Shin-etsu Chemical Co., Ltd., Tokyo, JP;
Inventors:
Assignee:
Shin-Etsu Chemical Co., Ltd., Tokyo, JP;
Primary Examiner:
Int. Cl.
CPC ...
C01B 33/035 (2006.01); C01B 33/037 (2006.01); C30B 23/00 (2006.01); C30B 29/06 (2006.01);
U.S. Cl.
CPC ...
C01B 33/035 (2013.01); C01B 33/037 (2013.01); C30B 23/00 (2013.01); C30B 29/06 (2013.01);
Abstract
A clean and high-purity polycrystalline silicon mass having a small content of chromium, iron, nickel, copper, and cobalt in total, which are heavy metal impurities that reduce the quality of single-crystal silicon, can be obtained from a silicon rod by before crushing a polycrystalline silicon rod, removing at least 70 mm of a polycrystalline silicon portion from the electrode side end of the polycrystalline silicon rod extracted to the outside of a reactor is provided. Thereby, the polycrystalline silicon portion in which the total of the chromium, iron, nickel, copper, and cobalt concentrations in a bulk is not less than 150 ppta can be removed.