| 摘要 |
PURPOSE:To obtain an oxide single crystal without cracking or bending with good reproducibility, by providing a specific temperature gradient to a part just on a melt of a raw material for an oxide single crystal charged into a crucible and pulling up and growing a crystal. CONSTITUTION:A raw material for an oxide single crystal, e.g. a raw material consisting of LiTaO3, in an amount of about 13kg is charged into a crucible 5 having about 150mm diameter, about 150mm height and about 2mm thickness and temperature is adjusted to about 1,290 deg.C to melt the raw material. An opening area between the upper lid 10 and holding rod 11 is adjusted to keep the temperature gradient in a part 5mm above a melt 14 to 46-75 deg.C/cm, e.g. 68 deg.C/cm. On the other hand, a seed 12 which is LiTaO3 single crystal and has a pulling up direction of X-axis is attached to the lower end of the holding rod 11, which is then lowered to contact the melt. The seed is subsequently pulled upward while being rotated to grow a crystal, which is then cut off from the melt and cooled. As a result, the aimed single crystal 13 of good quality without causing cracking and bending is obtained.
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