M. H. TAVAKOLI, T. N. MOSTAGIR

Copyright © 2012 SciRes. CSTA

120

From the computational results described above, we can

conclude:

The spatial structure of electromagnetic fields and

generated heat is a complex function of several pa-

rameters such as setup geometry and driving current

shape;

The electromagnetic fields distribution within the cru-

cible and afterheater as well as the RF-coil is not uni-

form. This electromagnetic fields nonuniformity causes

a nonuniform heating pattern in the crucible and af-

terheater, which in turn leads to a nonuniform tem-

perature profile in the growth system.

A square input current results in a high intense heating

of the crucible and afterheater while a sawtooth wave-

form leads to a low heating intensity in that part of the

system. Different amount of produced energy in the setu

is due to differences in the intensity and distribution of

the electromagnetic fields. Understanding the physics of

these n-

No. 3-4, 1989, pp. 792-826.

doi:10.1 (8

p

properties is important during designing of an i

duction system for certain crystal growth applications.

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