Linearization approaches in VGF models: decoupling global radiation transfer and the Stefan problem

Simplified theoretical models are presented for the highly coupled phenomena of heat transfer, convection and solidification during VGF crystal growth. The models are essential in order to inverse the general approach: optimal conditions at the solidification front can be translated into temperature conditions at the heaters and the corresponding heater regimes. The Stefan problem of the unknown geometry of the solidification front is solved in a simplified analytical way in good approximation with the full numerical solution.