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. 17, 2017
Filed:
Mar. 01, 2013
Sumco Corporation, Tokyo, JP;
Daichi Yagi, Tokyo, JP;
Takahiro Abe, Tokyo, JP;
SUMCO CORPORATION, Tokyo, JP;
Abstract
Casting polycrystalline silicon includes placing a bottomless cooling crucible divided at least partially in the axis direction into a plurality of parts in the peripheral direction and having an inner surface coated with a release agent containing nitrogen, in an induction coil of a chamber charged with an inert gas; melting a raw material of polycrystalline silicon in the bottomless cooling crucible by electromagnetic induction heating using the induction coil; and pulling out the molten silicon downward while cooling and solidifying it. Pullout of the solidified molten silicon is performed through adjusting the carbon concentration of the molten silicon to 4.0×10atoms/cmor more to 6.0×10atoms/cmor less, the oxygen concentration thereof to 0.3×10atoms/cmor more to 5.0×10atoms/cmor less, and the nitrogen concentration to 8.0×10atoms/cmor more to 1.0×10atoms/cmor less.