Computational modeling of CdZnTe crystal growth from the melt

A theoretical model of binary alloy solidification is formulated using the mass, momentum and energy balances in the liquid, and the mass and energy balances in the solid. The interface between the solid and liquid phases is modeled as a discontinuity surface where the mass, momentum and energy balance conditions are expressed. The linear theory of mixtures is employed in modeling the two-component system. The numerical solution of the mathematical model is performed using the Galerkin finite element method in a 2-D approximation with the cylindrical symmetry and the moving boundary problem is solved by a front-fixing technique. Computer implementation of the numerical model is then performed. In a practical application of the computational model, the process of CdZnTe crystal growth using the vertical Bridgman method and the vertical gradient method is simulated. The influence of principal adjustable parameters of both crystal growth techniques is studied, and these parameters are optimized. Also, the effects of uncertainty of material data and of second-order material parameters are analyzed.