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:
Oct. 07, 2025
Filed:
Mar. 06, 2023
Sumco Corporation, Tokyo, JP;
Keiichi Takanashi, Saga, JP;
Ippei Shimozaki, Imari, JP;
SUMCO Corporation, Tokyo, JP;
Abstract
A crystal puller apparatus comprises a pulling assembly to pull a crystal from a silicon melt at a pull speed; a crucible that contains the silicon melt; a heat shield above a surface of the silicon melt; a lifter to change a gap between the heat shield and the surface of the silicon melt; and one or more computing devices to determine an adjustment to the gap using a Pv-Pi margin, at a given length of the crystal, in response to a change in the pull speed. The computer-implemented method by a computing device comprises determining a pull-speed command signal to control a diameter of the crystal; determining a lifter command signal to control a gap between a heat shield and a surface of a silicon melt from which the crystal is grown; and determining an adjustment to the gap, in response to a different pull-speed, using a Pv-Pi margin.