Reactive ion etching of Si by Cl and Cl2 ions: Molecular dynamics simulations with comparisons to experiment

Abstract

We present results of molecular dynamics simulations of reactive ion etching (RIE) of a reconstructed Si(100)(2×1) surface. The existing Stillinger–Weber interatomic potential for Si/Cl of Feil et al. has been modified by correcting the Si–Si bond strength for a SiCln moiety bound to a Si surface and the Si–Cl bond strength in SiClm molecules. This potential has been used to study RIE of Si by Cl and Cl2 ions. The calculated properties such as the Si yield, product stoichiometry, stoichiometry of the chlorosilyl surface, and Cl content of the chlorosilyl layer are in reasonable agreement with experiment. The dissociative chemisorption probability of Cl2 on Si(100)(2×1) as a function of energy has been simulated and the results are in reasonable agreement with experiment.