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:
Mar. 22, 2005
Filed:
Feb. 20, 2001
Applicants:
Hiroyo Haga, Utsunomiya, JP;
Makoto Kojima, Utsunomiya, JP;
Shigemi Saga, Utsunomiya, JP;
Inventors:
Assignee:
MEMC Electronic Materials, Inc., St. Peters, MO (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C30B015/22 ;
U.S. Cl.
CPC ...
Abstract
A process for preparing a single crystal silicon in accordance with the Czochralski method, is provided. More specifically, by quickly reducing the pull rate at least once during the growth of the neck portion of the single crystal ingot, in order to change the melt/solid interface shape from a concave to a convex shape, the present process enables zero dislocation growth to be achieved in a large diameter neck within a comparably short neck length, such that large diameter ingots of substantial weight can be produced safely and at a high throughput.