| 摘要 |
A pulling shaft carries a seed crystal holder and moves it vertically to pull a crystal upward from a melt in a crucible. The pulling shaft is rotated by a drive to cause the crystal to rotate while being pulled. A slippage device is provided to permit a difference between rotational speeds of the pulling shaft and the seed crystal. The slippage device may be incorporated in a crystal holder having an inner holder fixed to the seed crystal, an outer holder fixed to the shaft, and a friction bearing therebetween which prevents undue torsional stress from being transmitted to the crystal. |
