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:
Jul. 03, 2001
Filed:
Dec. 07, 1999
Applicant:
Inventors:
Aaron W. Johnson, Vancouver, WA (US);
Aaron L. LaBrie, Vancouver, WA (US);
Randall Spradlin, Battle Ground, WA (US);
Assignee:
SEH America, Inc., Vancouver, WA (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C30B 1/500 ;
U.S. Cl.
CPC ...
C30B 1/500 ;
Abstract
A crystal pulling apparatus is disclosed which employs the Czochralski method. The crystal pulling apparatus is operated while a containing a crucible of molten material, while maintaining the growing chamber under a controlled pressure of less than atmospheric. In the event of a vacuum pump unexpectedly ceasing operation, power to the heater is terminated, thus allowing the molten material to solidify. In such an event, a second vacuum pump can readily be attached to the growing chamber thus restoring pressure control, and allowing power to the heater to be restored.