MICROSEGREGATION IN CRYSTAL-GROWTH FROM THE MELT - AN ANALYTICAL APPROACH

The influence of interface velocity variations on microsegregation is modelled analytically using a boundary layer formulation and a perturbation approach. The theoretical correlations between interface velocity and concentration fluctuations are seen to compare well with existing numerical and experimental data, meaning that the solute boundary layer formalism is well adapted to the study of microsegregation. A possible field of application of this work is the derivation of the allowable pulling device instabilities in a crystal growth furnace.