Bismuth Oxychalcogenides for Leading-edge Devices

The continuous miniaturization of electronic devices is limited by the physical properties of established materials such as silicon. As transistor dimensions shrink below the 10- nanometer scale, issues like power dissipation, performance degradation, and interface instability become more pronounced. To overcome these challenges, novel material systems applicable for ultrascaled electronic devices are urgently needed. This project investigates bismuth oxychalcogenides, particularly the layered compound Bi2O2Se, as a promising platform for next-generation nanoelectronics. Unlike conventional two-dimensional materials such as MoS2 or graphene, Bi2O2Se features a unique "zipper" structure that provides both stability and excellent electronic properties. However, what really sets this material apart is its native high-k oxide Bi2SeO5, which can form directly through controlled oxidation of the semiconductor. This intrinsic semiconductorinsulator structure offers a unique solution to overcome long-standing interface challenges in transistor technology. The project aims to systematically analyze the layer-by-layer oxidation mechanisms of Bi2O2Se into Bi2SeO5 at the atomic level using advanced computational simulations. Molecular dynamics, electronic structure calculations and machine learningbased interatomic potentials will be used to model the formation of the oxide, its phase stability, and defect dynamics. The role of vacancies, impurities, and doping strategies will be explored to optimize the electronic properties and to evaluate their impact on critical device parameters. Subsequently, the project will assess different metal-semiconductor and metal-insulator interfaces to optimize the contact resistance and suppress oxygen-related degradation. Simulation results will feed into device-level modeling frameworks to predict realistic performance under operating conditions. The generated data and models will be made publicly available, providing a valuable resource for both academic and industrial research on future electronic devices. By integrating materials modeling, defect analysis, and electronic transport simulations, this project contributes to the development of scalable 2D semiconductorinsulator systems. The project aims to improve our understanding of zipper materials at the atomic level, thereby unlocking their potential for groundbreaking applications. This advancement could enable faster, energy-efficient and more compact processors and high-performance electronics suitable for AI, sensing, and communication applications.