摘要 |
When a pulled single crystal becomes heavier, the strength of a seed crystal holder made of a carbon material is not sufficient, leading to falling of the single crystal. On the other hand, a seed crystal holder made of metal causes heavy metal contamination, or the strength thereof deteriorates early because of thermal fatigue. Accordingly, a seed crystal holder, comprising an inner cylindrical body made of metal which directly holds a seed crystal, and a carbon cylindrical body arranged around the inner cylindrical body which covers the periphery thereof, is used.
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