Simulations of Si and SiO2 etching in SF6 + O2 plasma

Chemical etching of Si and SiO2 in SF6 + O2 plasma is considered. The concentrations of plasma components are calculated using values extrapolated from experimental data. Resulting calculations of plasma components are used for the calculation of Si and SiO2 etching rates. It is found that the reaction constants for reactions of F atoms with Si atoms and SiO2 molecules are equal to (3.5 ± 0.1) × 10−2 and (3.0 ± 0.1) × 10−4, respectively. The influence of O2 addition to SF6 plasma on the etching rate of Si is quantified.