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. 14, 1998
Filed:
Aug. 08, 1996
Harold W Korb, Town & Country, MO (US);
Sadasivam Chandrasekhar, Chesterfield, MO (US);
Robert J Falster, Milan, IT;
Joseph C Holzer, Manchester, MO (US);
Kyong-Min Kim, St. Charles, MO (US);
Steven L Kimbel, St. Charles, MO (US);
Larry E Drafall, St. Charles, MO (US);
MEMC Electronic Materials, Inc., St. Peters, MO (US);
Abstract
A Czochralski method of producing a single crystal silicon ingot having a uniform thermal history from a silicon melt contained in a crucible coaxial with the ingot. In the process the pulling rate of the end-cone of the ingot is maintained at a relatively constant rate which is comparable to the pulling rate for the second half of the main body of the ingot. During the pulling of the end-cone of the crystal at a constant rate, the process may be further refined by, either independently or in combination, increasing the heat supplied to the melt, reducing the crystal rotation rate and/or reducing the crucible rotation rate. The second half of the main body of a single crystal silicon ingot grown in accordance with this process exhibits a relatively uniform axial concentration of flow pattern defects and amount of oxygen precipitated.