Molecular dynamics simulation of the thermal-caused material removal process by the SPM-based electric nanofabrication

Abstract

This paper intends to study the phenomena of thermal-caused material modifications in the principle of nanoscale electro spark during the SPM-based electric lithography. Since the direct observation of the electro spark process seems impossible in the nanoscale gap region, the molecular dynamics (MD) simulation method is applied to help investigate the influence of the thermal effect due to the Joule heating generated by the electro spark. The simplified heat source model is constructed based on the local temperature profile of the sample material beneath the tip, which is calculated through the Joule heating equation by the finite element method (FEM). The material removal process of local Cu and graphite sample subjected to the heat input is respectively simulated by the MD method to semi-quantitatively identify the thermal effect on the SPM-based electric nanofabrication results.