PULLING OF SINGLE CRYSTAL AND ITS APPARATUS

摘要

PROBLEM TO BE SOLVED: To provide a method for pulling a single crystal capable of safely pulling up a single crystal while maintaining a high quality state even if the single crystal has a high weight when the single crystal is pulled by a Czochralski process. SOLUTION: The first necking part, an enlarged part 18 and the second necking part 20 are formed under a seed crystal 16 hung and hold by hanging tool 15 at the lower end of a wire 14 in order, and a hanging and holding tool 9 and 9 is closed so that holder parts 9a and 9a can adjoin but not touch the second necking part 20 when the second necking part 20 is pulled a prescribed position while pulling up the hanging tool 15. Further, the hanging tool 15 and the hanging and holding tool 9 and 9 are relatively moved in the vertical direction and the enlarged part 18 is held so as to put on and bring into contact with the holder parts 9a and 9a and thereafter the ratio of the load borne by the hanging tool 15 to that borne by the hanging and holding tool 9 and 9 is regulated to 5:5. The pulling thereafter is performed by the hanging and holding tool 9 and 9.