Deposition rates in thermal laser epitaxy: simulation and experiment

The modeling of deposition rates in thermal laser epitaxy (TLE) is essential for the accurateprediction of the evaporation process and for improved dynamic process control. Wedemonstrate excellent agreement between experimental data and a model based on a finiteelement simulation that describes the temperature distribution of an elemental source whenirradiated with continuous wave laser radiation. The simulation strongly depends on thethermophysical constants of the material, thermal conductivity, specific heat capacity, density,reflectivity and thermal emissivity, data of which is lacking for many elements. Effective valuesfor the parameters may be determined with precision by means of an unambiguous referenceprovided by the melting point of the material, which is directly observed during theexperiments. TLE may therefore be used to study the high temperature thermophysical andoptical properties of the elements.