Molecular dynamics simulations of the sputtering process of silicon and the homoepitaxial growth of a Si coating on silicon

Molecular dynamics simulations of the sputtering process of silicon by Ar atoms in the low energy range, 20 eV-1000 eV, were performed using the IMD software package and the commercial software Materials Explorer 4.0 from Fujitsu Ltd. with the combination of the Tersoff potential and the Ziegler-Biersack-Littmrk (ZBL) potential in order to get more insight into the sputter process itself and to extract data comparable to experiments. The analysis of the sputter yield as a function of argon impact energy, surface impact coordinate and of crystal orientation was performed. These simulation results were compared with experimental values as determined by Ar ion etching in a microwave plasma and measurement of the etch depth and etch time. A good agreement between experiments and simulations was found. Physical parameters such as binding energy of the Si (0 0 1) surface, vacancy energy and vacancy migration energy were also determined in order to explain the simulation results of the sputter process. Finally, the coating process of a silicon substrate by Si atoms was simulated using the Si sputter results as input parameters.