Ballistic transport in 5.1 nm monolayer boron phosphide transistors for high-performance applications

Boron Phosphide is reported to be a semiconductor material with anisotropy, tunable bandgap, and high carrier mobility. We study the performance of 5.1 nm metal–oxide–semiconductor field-effect transistors (MOSFETs) based on boron phosphide using quantum transport simulation. The calculated results show that the on-state current can fulfill the requirements of the International Semiconductor Technology Roadmap (ITRS) for high-performance (HP) devices at the optimal doping concentration, but the gate control capability is not ideal. Furthermore, it is found that the gate control capability and on-state current can be significantly improved with the length being 1 nm by using the underlap (UL) structure. We also study the performance of boron phosphide MOSFET with different gate lengths (5–8 nm), and the results suggest that the shorter the gate length, the worse the gate control capability. Interestingly, the p-type boron phosphide MOSFET always outperforms the n-type MOSFET. This work will provide a new reference for the development of two-dimensional (2D) semiconductor devices.