| 摘要 |
PURPOSE:To stabilize the control loop of crystal growth and to obtain a single crystal having excellent uniformity of cross-sectional diameter, by detecting the weight of a single crystal together with rotational angle in the pulling of a single crystal via a load cell under rotation and controlling the growth using a means for correcting the value detected by the load cell. CONSTITUTION:A single crystal 4 is grown by heating and melting a raw material in a crucible 2 with a heater 3 under controlled condition and pulling up a single crystal from the molten raw material 1 using a pulling rod 5 suspended from a load cell 6 while rotating the rod with a motor 8. In the above process, a detected weight F transmitted from the load cell 6 and an output 20a transmitted from a rotational angle sensor 20 are inputted into a means 21 for correcting the valve detected by the load cell. The error term DELTAF caused by the rotation is calculated and is subtracted from the detected value transmitted from the load cell. A control loop composed of a power-controlling apparatus 11, a heating device 12 and a heater 3 is stably controlled via a controlling circuit 10 and the single crystal 4 is pulled up under heating and melting the raw material.
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