Atomistic Modeling of Oxide Semiconductors

Our research examines oxide semiconductor field-effect transistors (OSFETs), which hold promise for back-end-of-line (BEOL) memory and logic applications. OSFETs offer advantages over silicon devices because their electronic properties remain robust even in the amorphous state, allowing them to be manufactured at low temperatures compatible with BEOL processes. Additionally, their wide band gaps can be engineered to yield extremely low leakage currents—an important feature for memory applications like gain cells—making OSFETs attractive for 3D integration of logic and memory.

This project is dedicated to deepening our understanding of the material-level physics of amorphous oxide semiconductors. One focus is on material composition: we study the choice and concentration of secondary cations such as Ga₂O₃, WO₃, ZnO, and SnO₂ in In₂O₃ based amorphous semiconductors. Another focus is the role of interfaces, including investigating phenomena like the interface dipole V_Th shift effect. By exploring these aspects using simulation-based methods (including density functional theory, molecular dynamics with custom machine-learned potentials, and non-equilibrium Green’s function techniques) our work aims to inform device-level modeling and experimental efforts, ultimately contributing to the broader adoption of OSFET technology in advanced electronic applications.