Investigation of the heat exchange processes during growth of basal-plane-faceted sapphire ribbons by the Stepanov method

A three-dimensional model is proposed for the global heat exchange during growth of basal-plane-faceted sapphire ribbons. The model is based on the method for solving three-dimensional problems of radiative heat transfer in complex regions with diffusely and specularly reflecting boundaries. The temperature distributions in the ribbon and elements of the thermal zone are investigated. It is shown that the developed model correctly reflects the main features of the processes of heat exchange in the crystallization setup and makes it possible to purposefully modify the thermal zone.