Simulations of Formation of Nanostructure in Silicon Surface by Single Slow Highly Charged Ion

Abstract

To understand the mechanisms of surface erosion induced by slow highly-charged ion (SHCI) bombardment, the surface nanostructure formation in Si (111) surface by single Xe44+ ion was studied by using molecular-dynamics (MD) simulations, based on analyzing the multiple electron emission of the substrate. The time evolutions of the temperature, energy, pressure and density of the substrate have been systematically studied. The results show the bombardment of the incident SHCI resulting in an explosive event in the surface. A shock wave propagating at ~104 m/s is formed in the system during the initial 175 fs. After this initial shock, many particles are ejected from the surface since the extreme non-equilibrium of the system. And at t=370 fs, a crater-like nanostructure with diameter of ~40 Å and depth of ~18 Å is formed at the incident site.