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Abstract

A method for growing a silicon crystal by a Czochralsky method, wherein, let a pulling speed be V (mm/min) and an average value of an in-crystal temperature gradient in a pulling axis direction within a temperature range, a silicon melting point to 1350.degree. C., be G (.degree. C./mm), V/G ranges from 0.16 to 0.18 mm.sup.2/.degree. C. min between a crystal center position and a crystal outer periphery position, and a ratio G outer/G center of an average value G of an in-crystal temperature gradient in a pulling axis direction within a temperature range, a silicon melting point to 1350.degree. C., at a crystal outer surface to that at a crystal center is set to up to 1.10 to thereby obtain a high-quality perfect crystal silicon wafer. Such a perfect crystal silicon wafer, wherein an oxygen concentration is controlled to up to 13.times.10.sup.17 atoms/cm.sup.3, an initial heat treatment temperature is at least up to 500.degree. C. and a temperature is raised at up to 1.degree. C./min at least within 700 to 900.degree. C., thereby making uniform a wafer radial distribution to an arbitrary oxygen precipitation density level.

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