Author(s)

P Prikryl, K Segeth & R Cerný

Abstract

A computational model of pulsed laser-induced phase transitions in binary semiconducting systems is presented. The nonequilibrium phase change processes due to the high velocities of the interface are modeled using the concept of the Wilson-Frenkel interface response function and nonequilibrium segregation coefficients are considered. The computational implementation based on the finite element method is described. In a practical application of the computational model, the melting and solidification of CdTe and CdZnTe induced by Nd:YAG laser are simulated. The temperature and concentration fields, the position and velocity of the phase interface, and the reflectivity of the incident laser beam are calculated as functions of laser energy density. It is concluded that the laser energy densities applied in the experimental work should be significantly lower here than those in the case of basic semiconductors such as Si or Ge, which is mainly due to the lower thermal conductivity of CdTe and CdZnTe. This may result in necessary adjustments of current experimental setups.

Keywords