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.

Date of Patent:
Jan. 30, 2024

Filed:

Feb. 27, 2019
Applicant:

Sumco Corporation, Tokyo, JP;

Inventors:

Wataru Sugimura, Tokyo, JP;

Ryusuke Yokoyama, Tokyo, JP;

Toshiyuki Fujiwara, Tokyo, JP;

Toshiaki Ono, Tokyo, JP;

Assignee:

SUMCO CORPORATION, Tokyo, JP;

Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C30B 15/26 (2006.01); C30B 15/16 (2006.01); C30B 29/06 (2006.01); C30B 30/04 (2006.01);
U.S. Cl.
CPC ...
C30B 15/26 (2013.01); C30B 15/16 (2013.01); C30B 29/06 (2013.01); C30B 30/04 (2013.01);
Abstract

A convection pattern estimation method of a silicon melt includes: applying a horizontal magnetic field of 0.2 tesla or more to a silicon melt in a rotating quartz crucible with use of a pair of magnetic bodies disposed across the quartz crucible; before a seed crystal is dipped into the silicon melt to which the horizontal magnetic field is applied; measuring temperatures at a first and second measurement points positioned on a first imaginary line that passes through a center of a surface of the silicon melt and is not in parallel with a central magnetic field line of the horizontal magnetic field as viewed vertically from above; and estimating a direction of a convection flow in a plane in the silicon melt orthogonal to the direction in which the horizontal magnetic field is applied on a basis of the measured temperatures of the first and second measurement points.


Find Patent Forward Citations

Loading…