| 摘要 |
PURPOSE:To produce high-quality single crystal having any diameter, by growing single crystal on seed crystal from a molded article partially immersed in raw material melt put in a crucible and forming a supercooled zone suitable for growth process. CONSTITUTION:Raw material melt is put in a crucible which is rising while being rotated through a supporting shaft. A molded article partially immersed in the melt is fixed by a bearer. The molded article has a small opening at the center and the part immersed in the melt consists of a slant side wall extending upward. Seed crystal is immersed in a supercooled zone of the melt in the molded article to attach crystal to the seed crystal, the seed crystal is pulled up, a shoulder part, a straight barrel part and a tail part of the growing single crystal are successively formed. In the above-mentioned single crystal pulling method, the crystal is pulled up while keeping the correlation shown by the formula S1<=S4<=S3<S2 when the relative velocity of the molded article based on the crucible is S1 in seeding process, S2 in shoulder forming process, S3 in straight barrel forming process and S4 in a tail forming process. Consequently, a proper supercooled zone is made corresponding to the diameter of formed single crystal to prevent dendrite formation.
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