PRODUCTION OF SILICON WAFER AND METHOD FOR GROWING SILICON SINGLE CRYSTAL

摘要

PROBLEM TO BE SOLVED: To produce a silicon wafer and a silicon single crystal free from grown-in defects. SOLUTION: A CZ-furnace in which the temp. gradient in the axial direction of the crystal surface at a high temp. part close to the melting point of silicon is smaller than that in the axial direction of the center part of the crystal is used. Crystal growth is carried out under such a condition that the center part of the crystal becomes a region free from defects, a region where stacking faults caused by oxidation are formed or a region where infrared scattering defects are formed. When the temp. gradient in the axial direction at the high temp. part close to the melting point of silicon is G' and the rate of pulling up is V, the rate of pulling up is controlled so that the V/G' value is kept constant against the change of temp. gradient G' in the axial direction with the progress of crystal growth. An objective V/G' value is maintained without changing the mean rate V of pulling up.