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.