Surface molecular dynamics of <f>Si/SiO2</f> reactive ion etching

Classical molecular dynamics (MD) simulations of Si and <f>SiO2</f> etching by halogens (Cl or F) have been performed to study surface reaction mechanisms for plasma etching. The interatomic potentials for Si–O–Cl and Si–O–F systems are constructed based on potential energy data obtained from ab initio quantum mechanical calculations. The etch rates and selectivities obtained from these MD simulations are in good agreement with presently available experimental observations. We have also observed in MD simulations that surface conditions under reactive ion etching (RIE), where low-energy neutral halogens play important roles in enhancing etch rates, differ significantly from those under beam etching. [Copyright &y& Elsevier]