Simulating Proton Radiation Effects in Indium Oxide Using Cascade Molecular Dynamics Simulations

Metal oxide (MO) materials, such as Indium Oxide (In₂O₃), are transparent semiconductors with significant potential in catalysis, energy storage, and optoelectronics. In this study, we employed molecular dynamics (MD) simulations to study the effect of ion beam modification on the electrical, structural, and mechanical properties of In₂O₃ under dual-dose irradiation conditions. A custom potential was tabulated by combining the Ziegler-Biersack-Littmark (ZBL) potential for short-range atomic interactions with Buckingham and Coulombic potentials for long-range forces, to enable accurate atomic-scale simulations in a high-energy irradiation environment. The dual-dose irradiation was then simulated by applying two-step Primary Knock-on Atom (PKA) cascade irradiation simulations. First, low-energy irradiation was applied to create displacements and primary defects in the system, followed by a second high-energy simulation, mimicking the experimental energy inputs. Experiments have shown improvement in electrical properties, i.e., conductivity, potentially due to recovery of defects. Our MD simulations revealed the mechanisms behind defect recovery, specifically by tracking the evolution of oxygen vacancies which plays a key role in increasing the concentration of charge carriers and enhancing electrical conductivity. This work provides fundamental insights into the defect dynamics of ion beam modification of MO materials and offers potential pathways to improve the mechanical and electrical properties of such materials, particularly in radiation-intensive environments.