Molecular dynamics simulations of Cl2+ impacts onto a chlorinated silicon surface: Energies and angles of the reflected Cl2 and Cl fragments

Abstract

We describe the energy and angle distributions of reflected Cl2 molecules and Cl atom fragments obtained from molecular dynamics (MD) simulations of Cl2+ ion impacts onto a chlorinated silicon surface. We simulated Cl2+ ion impacts onto a silicon surface with 1 monolayer (ML) of adsorbed Cl atoms. The ion incident energies Ei were 20, 50, and 100 eV. We varied the ion incident angles θi from 0° to 85° from the surface normal. We report the Cl2 dissociation probability, as well as the scattering probabilities for both the Cl2 molecules and the Cl atom fragments. The effects of Ei and θi on these quantities are discussed. For the 100 eV Cl2+ impacts with θi⩾75°, we describe the distributions of energies Er and angles (polar θr and azimuthal φr) for the reflected Cl2 molecules and Cl atom fragments. In addition, we compare the average energies of the reflected molecules and atoms with the predictions of two simple models based on the binary collision approximation.