SINGLE CRYSTAL PULLING-UP DEVICE

摘要

PROBLEM TO BE SOLVED: To prevent a raw material melt from solidifying even when the heating of the raw material melt in a crucible of a single crystal pulling-up device of a Czochralski method is impossible. SOLUTION: The heating state is maintained by a back up controller 21 of a back up system B to maintain the melting state of the raw material melt 15 of the single crystal pulling-up, machine 1 by changing over the relays of a signal change over circuit 24 at the time when the heating state is no more maintainable by a certain reason when the pulling-up machine is operated while the heating control of the heater for heating the raw material melt is executed by a main controller 16 of a main system M.