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:
Jan. 01, 2002
Filed:
Jul. 11, 2000
Shin-Etsu Handotai Co., Ltd., Tokyo, JP;
Abstract
A method for producing a silicon single crystal, wherein, when a silicon single crystal is grown by the Czochralski method, the crystal is pulled with such conditions as present in a region defined by a boundary between a V-rich region and an N-region and a boundary between an N-region and an I-rich region in a defect distribution chart showing defect distribution which is plotted with D [mm] as abscissa and F/G [mm /° C.·min] as ordinate, wherein D represents a distance between center of the crystal and periphery of the crystal, F/G [mm/min] represents a pulling rate and G [° C./mm] represents an average temperature gradient along the crystal pulling axis direction in the temperature range of from the melting point of silicon to 1400° C., and time required for crystal temperature to pass through the temperature region of from 900° C. to 600° C. is controlled to be 700 minutes or shorter, and a silicon single crystal wafer grown by the Czochralski method, which is a silicon single crystal wafer having N-region for its entire plane, and does not generate OSFs by a single-step thermal oxidation treatment, but generates OSFs by a two-step thermal oxidation treatment. According to the method, a silicon single crystal wafer of an extremely low defect density, which has the N-region for the entire plane of the crystal, is obtained by the CZ, while maintaining high productivity.