A molecular dynamics study of H radical bombardment of CH3 : Si(1 0 0)- comparison of simulation and experiment

Molecular dynamics (MD) simulations have been carried out to examine the bombardment of a methylated Si(1 0 0) surface with thermal (300 K) and elevated energy (1 and 5 eV) H radicals. The simulations are based on a reactive empirical bond order (REBO) potential energy function (PEF) for Si-C-H interactions. The observed product distributions and etch mechanisms for the removal of the CH3 from the surface are consistent with experimental observations in the literature. All of the CH3 groups are removed as SixCyHz species, with SiCH6 being the predominant etch product. No formation of CH4 is seen. Additionally, the accuracy of the REBO PEF for thermal processes is examined and the pertinent limitations are discussed as the basis for future development of simulations of plasma-surface interactions. (fast track communication)