| 摘要 |
<p>A binary controller for a crystal body used for a single crystal pull-up production method represented by the Czochralski method for converging the crystal growth diameter and the seed lift speed to their desired values. The seed lift speed controlled variable (SLC) and the temperature controlled variable (TC) are generated independently of each other on the basis of the deviation signal (DEV) of the diameter control parameter. As a result, the seed lift speed acts on the convergence of the crystal growth diameter, and the temperature controlled variable suppresses the variation of the shortage of heat energy and converges the seed lift speed varied by the convergence action of the crystal growth diameter. Hence the binary control of both the crystal growth diameter and the seed lift speed are preferably achieved.</p> |
