| 摘要 |
PROBLEM TO BE SOLVED: To provide the production method of silicon single crystal which prevents polycrystallization of single crystal and breakage and fall from a neck part. SOLUTION: This detector is provided with a camera 3 disposed in the outside of a silicon single crystal growth chamber and for detecting rotation of a crystal in the chamber, a memory 22 for processing a signal from the camera 3 and storing it, and an operation processor 21 for comparing the signal from the camera 3 with another signal of the memory 22 and discriminating production of abnormal oscillation of a single crystal 6. In addition, in a method for detecting the abnormal oscillation of a silicon single crystal, it is judged that the abnormal oscillation is produced in the single crystal when a deviation between a time interval of a signal newly output from the detector and its average value exceeds a specified value. The discrimination signal of the abnormal oscillation obtained from the above-mentioned value is input to a silicon rotation driver 12, and its revolving speed is changed, so that the abnormal oscillation can be avoided. |
