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:
Feb. 29, 2000
Filed:
Jan. 12, 1998
Aaron LaBrie, Vancouver, WA (US);
Masahiko Baba, Vancouver, WA (US);
SEH America, Inc., Vancouver, WA (US);
Abstract
A method and apparatus for measuring and controlling the diameter of a silicon single crystal ingot grown by the Czochralski technique using dual optical cameras focused on diametrically opposed edges of the meniscus of the growing crystal to measure the actual crystal diameter. The crystal growth parameters can be adjusted in response to the measured diameter to maintain a constant, desired diameter. The method and apparatus of the invention provide a continuous accurate measurement of the crystal diameter and avoid unnecessary adjustments to the crystal growth conditions resulting from diameter measurement errors due to the effects of crystal orbit, melt level changes and camera angle variations.