| 摘要 |
The present invention provides control of single crystal growth after the recovery from power failure when controlling crystal growth in an automatic mode. A source voltage is supplied to a controller 70 through a no-break power supply 62. At the time of recovery from power failure, the controller continues the automatic operation mode with the same control output as that stored when power failure is detected (84, 85) if the power failure time t is t </=t1 (for example, 1 second), switches the control mode to the manual control mode with the same control output as that stored when the power failure is detected (86, 87) if t1<t</=t2 (for example, 5 seconds), stops the crystal growth operation and switches the control mode to the manual control mode (88, 89) if t2<t</=t3 (for example, 600 seconds), and separates the grown crystal from a melt 22 by upwardly moving the crystal and upwardly moves a crucible 16 (90) if t>t3.
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