CHANGE IN VELOCITY IN SILICON MELT OF THE CZOCHRALSKI (CZ) PROCESS IN A VERTICAL MAGNETIC-FIELD

The influence of a magnetic field on the velociry of molten silicon has been characterized both theoretically and experimentally. The velocity decrease observed by X-ray radiography in the magnetic field is in good agreement with the results obtained by numerical modelling. It is found that the rate of decrease in velocity in a vertical magnetic field is well presented using the magnetic number rather than the Hartmann number. Accordingly, the analytical expression using the square of the magnetic number, M, well describes the velociry changes as v/v0 = (1 + M2/4)1/2 - M/2, for experimental as well as numerically calculated data.