Molecular dynamics simulation of 100 keV argon ion radiation effects in metals and comparison with stopping and range of ions in matter code

Abstract

Abstract Simulation is essential to analyse radiation-induced effects because energetic ions have short transit times within materials (Ar ions of 1 keV and 100 keV have transit times of 0.29 picoseconds and 29 femtoseconds respectively, through a 25 nm Al film). The binary collision approximation (BCA) is extensively used in simulations to study damage caused by energetic ions due to its computational efficiency. Stopping and Range of Ions in Matter (SRIM), a widely used Monte Carlo software using BCA, provides accurate ion ranges consistent with experiments. Molecular dynamics simulations are powerful computational method, where classical equations of motion are solved to track atomic movements from radiation damage, but computational resources required are heavier for this method. In our current effort, the energy transfer from 100 keV Ar+ to metal targets is analysed as a function of target properties, including melting temperature and atomic density, using these two methodologies. A detailed investigation of 100 keV Ar+ ion impact on metal targets is done using the classical Molecular Dynamics simulation program ‘MDRange’, which uses the Recoil Interaction Analysis (RIA) approximation, where the interaction between the ion and its closest neighbours is considered via a two-body potential. The correlation of energy transferred to the metal with the target properties is examined considering the physical approximations of each technique.