| 摘要 |
PROBLEM TO BE SOLVED: To suppress the occurrence of a dislocation at a shoulder part in a HMCZ method using horizontal magnetic field. SOLUTION: The process of squeezing for removing a dislocation and the successive diameter increasing process are carried out without applying magnetic field. At this time, the rotational frequency of a crucible is adjusted to be >=5 rpm, thereby the occurrence of dislocation at the shoulder part 12 is suppressed. As there is no magnetic field, the unstableness at squeezing process is avoided by increasing the rotational frequency of the crucible. When the process of growing the shoulder part 12a is finished and the process of growing the body part 12b is started, a magnetic field is applied, thereby the temperature of the melted liquid is raised and increasing of the diameter is stopped. When the convection of the melted liquid 13 is suppressed by applying the magnetic field, the rotational frequency of the crucible is rapidly changed to a stationary rotational frequency. At this time, the temperature of the melted liquid can be kept nearly constant even when the rotational frequency of the crucible is rapidly changed.
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