Molecular dynamics simulation of low-energy bombardment on Pt(111) surface

Abstract

The low-energy bombardments of noble metal atoms (Ni, Pd, Pt, Cu, Ag, Au) on Pt (111) surface are studied by molecular dynamics (MD) simulations. The atomic interaction potential with embedded atom is used in the simulation. The incident-energy effects on adatom yields, sputtering yields, and vacancy yields for different projectiles have been observed and summarized. When the incident energy Ein varies from 0.1 to 200 eV, surface atoms transfer layer by layer and the incident energy dependent transition occurs when the incident energy values are about 5 and 70 eV. When the incident energy is lower than 5 eV, projetiles are deposited as adatom and the value of defect yield is 0. While 70 eV > Ein > 5 eV, no atoms can be implanted into the depth beyond the second layer and the vacancy yield in the third layer is about 0. For the case of Ein > 70 eV, deposited atoms enter into the third layer. And then, vacancy occurs. Furthermore, defect yield sharply increases with the increase of incident energy. Based on the result of our MD simulations, a guide to the choice of optimum deposition parameters is suggested.