RAW MATERIAL FILLING METHOD, METHOD OF PRODUCING SINGLE CRYSTAL AND APPARATUS FOR PRODUCING SINGLE CRYSTAL

摘要

PROBLEM TO BE SOLVED: To provide a raw material filling method by which fracture of a quartz crucible and a recharge tube can be suppressed.SOLUTION: There is provided the raw material filling method in which a raw material is housed in a recharge tube including a quartz cylindrical member for housing the raw material and a cone valve for opening and closing an opening located at the bottom end of the cylindrical member, the recharge tube with the raw material housed therein is placed in a chamber, and the cone valve is lowered to open the opening at the bottom end of the cylindrical member, so that the raw material housed in the recharge tube is charged into a quartz crucible. The recharge tube and the quartz crucible are arranged in such a manner that the distance between the bottom end of the recharge tube and the raw material or melt in the quartz crucible is 200 mm or more and 250 mm or less when starting the raw material charge. The raw material is then charged while the quartz crucible and the cone valve of the recharge tube are simultaneously lowered in such a manner that the ratio (CL/SL) of a lowering speed (CL) of the quartz crucible to a lowering speed (SL) of the cone valve of the recharge tube is 1.3 or more and 1.45 or less.