Atomistic Insights into Oxidation of Chemical Passivated Silicon(100)Surface:Reactive Molecular Dynamic Simulations

Main observation and conclusion In this paper,a series of ReaxFF molecular dynamic simulations were performed to study the oxidation of chemical passivated silicon(100)surface,which was terminated with different n-alkyl chains.The simulated results showed that the oxidant species diffuse into Si substrate through peroxy-like structures during the oxidation process.During the oxidation process,the Si-alkyl(Si-C)covalent bond was stable and there is no occurrence of decomposition of the n-alkyl chains.In addition,the existence of n-alkyl monolayers on silicon surface did not change the initial reaction pathway of the oxidation process.The simulations indicated that the chemical passivation mechanism includes two parts,one is about the Si-C covalent bond occupying the active site of the reaction on Si(100)surface,and the other is about the oxygen penetrating Si-alkyl layers.The simulations also indicated that the chemical passivation of Si-alkyl is better for longer alkyl chains,which is consistent with the experimental observation.Our results have investigated the oxidation of chemical passivated silicon(100)surface at the atom level,which is helpful to comprehend the manufacture of semiconductor devices like metal-oxide-semiconductor(MOS)devices in the experiments.