| 摘要 |
PROBLEM TO BE SOLVED: To easily apply a cusp magnetic field in an always optimum state and to reduce the cost with respect to equipment constitution, at the time of pulling up a single crystal, in the equipment for applying a magnetic field to a raw material melt in a crucible and producing a single crystal by a pulling-up method. SOLUTION: In this equipment, a pair of super-conductive main coils 30a and 30b are connected in series and placed oppositely to each other on the upper and lower sides of the periphery of a crucible 16 filled with a melt 17, respectively, and also, an auxiliary super-conductive coil 31 which has a smaller magnetomotive force as compared with the super-conductive main coils 30a and 30b and the exciting current value and direction of which are variable, is placed right in the middle of the space between the main coils 30a and 30b. The exciting current of the auxiliary coil 31 is adjusted so as to optimize the cusp magnetic field. |
