DFT coupled with NEGF study of N-type MOSFET based on 2D Bi ₂ C ₃ semiconductor

As silicon-based FETs face scaling limits, two-dimensional (2D) material emerge as promising alternatives with potential to suppress short-channel effects and reduce power consumption. We present a comprehensive investigation of the novel 2D bismuth carbide (Bi₂C₃) semiconductor using first-principles density functional theory (DFT) calculations combined with non-equilibrium green's function (NEGF) quantum transport simulations. Electronic band structure calculations indicate that monolayer Bi₂C₃possesses a moderate direct bandgap, a sharp conduction band, and a low electron effective mass (0.48<i>m</i>₀). Device simulations reveal outstanding performance: a Bi₂C₃FET with a 10 nm channel length achieves an ultra-high on-state current (<i>I</i>_on) of 2540<i>μ</i>A<i>μ</i>m^-1while maintaining a high on/off current ratio (exceeding 10⁴), satisfying the requirements of the international technology roadmap for semiconductors (ITRS) for high-performance (HP) applications. Furthermore, scaling the channel length down to 5 nm still yields device performance compliant with ITRS specifications. Crucially, devices across different channel lengths exhibit fast switching speeds, low power-delay (<i>τ</i>), power-delay product, and excellent energy-delay product, fully meeting the ITRS HP targets. This study, for the first time, systematically evaluates the application potential of Bi₂C₃in MOSFETs via DFT-NEGF. Its excellent comprehensive performance metrics demonstrate that monolayer Bi₂C₃is a highly competitive candidate channel material for future HP integrated circuits.