| 摘要 |
PURPOSE:To enable repeated use of a crucible, by placing a detachable cylindrical upper member of a crucible on a bottom-closed lower member of a crucible, detaching and cleaning the upper member of crucible after use and combining the cleaned upper member with a new lower member of crucible. CONSTITUTION:A required amount of granular silicon raw material 10 is charged in a crucible 4 and heated with a heater 5. The silicon raw material 10 begins to melt from the bottom part to form molten silicon 9 and the liquid level reaches a level somewhat lower than the top edge of a lower member 4a of the crucible. A single crystal rod 9A is pulled up from the molten silicon keeping the above state. The lower member 4a of the crucible is deteriorated by the thermal fatigue generated in the lower member 4a, since the inner surface of the lower member 4a of crucible reacts with molten silicon 9 and is exposed to high temperature. On the contrary, such a deterioration does not take place in the upper member 4b of crucible because there is no direct contact of the upper member 4b with the molten liquid 9. After completion of the pulling-up of the single crystal, the upper member 4b of crucible is separated from a susceptor 3 after cooling all parts of the susceptor and washed to remove impurities attached to the surface of the upper member 4b.
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