MODEL-CALCULATIONS OF TEMPERATURE-PROGRAMMED SURFACE SEGREGATION

The investigation of the kinetics of surface segregation can reveal im portant information on the diffusion properties of the system near the surface. A promising way for an efficient experimental analysis of th e temperature dependence of the effective diffusion coefficients is th e temperature programmed segregation (TPS), in which the temperature i s increased linearly with time during the experiment. Model calculatio ns of the segregation kinetics during TPS have been performed on the b asis of the KTBIM (kinetic tight binding Ising model) for dilute binar y and ternary systems to investigate the applicability of this method in real systems. The results give hints on the conditions under which experimental results can be used to obtain the Arrhenius parameters of the effective diffusion coefficients of the segregating elements in r eal systems.