The field up to surface ratio 50 is the zero defect field from wafer rim in

摘要

PROBLEM TO BE SOLVED: To improve the yield of a device chip made from one silicon wafer by simply providing a silicon single crystal by a Czochralski method having bettered withstand voltage of oxide film especially in a circumferential part of a wafer without extremely reducing productivity. ;SOLUTION: This silicone single crystal wafer has a defect-free zone having no defective withstand voltage of oxide film in an area up to 50% surface area from the outer periphery of the wafer, especially in an area up to 30mm from the outer periphery of the wafer in a silicon single crystal wafer having a large aperture of ≥6 inches. The method for producing such a silicon single crystal comprises growing the single crystal at a pulling up rate of 80-60%, the limit pulling up rate of a characteristic pulling up device in pulling up the silicon single crystal by a Czochralski method.;COPYRIGHT: (C)1997,JPO