The pedestal method is an alternative to
the well-known floating zone method, both of which are
performed with high-frequency electromagnetic heating. Unlike
the floating zone method, in the pedestal method a single
crystal is pulled upwards from the melt. It allows one to
lower feed rod quality requirements and simplify the process
control due to the absence of open melting front. As the
pedestal method has not been widely used in industry for
silicon crystals, its development requires extensive numerical
modelling. The present work describes application of the
previously created mathematical model for crystals with
diameters higher than it is currently possible in the
experimental setup, as well as for the cone growth phase.
Supplementary free surface heating, that prevents melt centre
freezing during the seeding phase, has been added at the
beginning of cone phase. After multiple sets of simulations,
an optimal scheme of heating control for cone growth was
proposed.
Keywords: single silicon
crystal growth, numerical modelling, pedestal method
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