METHOD OF GROWING CYLINDRICAL TUBULAR CRYSTALLINE BODIES

摘要

A method of growing cylindrical tubular crystalline bodies having impurities distributed therein at improved levels of uniformity relative to the distribution of impurities in non-cylindrical tubular crystalline bodies which are not rotated during the growth thereof. The method involves forming a cylindrical tubular crystalline body by the EFG process including rotating the crystalline body at about 35-65 rpms the entire time the body is being pulled from the forming die. Crystalline bodies having a wall thickness of 5 mils, plus or minus 0.5 mils have been grown by the method.