| 摘要 |
PROBLEM TO BE SOLVED: To prevent an outflow of a high temperature raw material to the outside of a production device and corrosion of the wall of a device furnace by the flown-out raw material in the case when the high temperature raw material is flown out by an accident in a semiconductor single crystal production device based on a CZ method, and to provide a method of evaluating a graphite member suitable for preventing the outflow. SOLUTION: A quartz crucible 14a is provided at the inside of a furnace 12 of a production device. A protective crucible 14b, a crucible stand 18 and a crucible supporting shaft 20, which may be brought into contact with a molten raw material M when it flows out, are constituted of graphite members. Isotropic graphite having a bulk density of 1.70 to 1.90 g/cm3 is used for producing the graphite members. Or, a graphite material having such a characteristic that the rate of dimension change of a part dipped in a silicon melt for a time between 10 to 20 min is <=5% is used for producing the graphite members. Further, isotropic graphite such that its ash content is <=20 ppm is used.
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