Promising Properties of a Sub-5-nm Monolayer <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline" overflow="scroll"><mml:msub><mml:mrow><mml:mi>Mo</mml:mi><mml:mi>Si</mml:mi></mml:mrow><mml:mn>2</mml:mn></mml:msub><mml:msub><mml:mrow><mml:mrow><mml:mi mathvariant="normal">N</mml:mi></mml:mrow></mml:mrow><mml:mn>4</mml:mn></mml:msub></mml:math> Transistor

Abstract

Two-dimensional (2D) semiconductors have attracted tremendous interest as natural passivation and atomically thin channels could facilitate continued transistor scaling. However, air-stable 2D semiconductors with high performance are quite elusive. Recently, an extremely-air-stable ${\mathrm{Mo}\mathrm{Si}}_{2}{\mathrm{N}}_{4}$ monolayer was successfully fabricated [Hong et al., Science 369, 670 (2020)]. To further reveal its potential application in sub-5-nm metal-oxide-semiconductor field-effect transistors (MOSFETs), there is an urgent need to develop integrated circuits. Here, we report first-principles quantum-transport simulations on the performance limits of n- and p-type sub-5-nm monolayer (ML) ${\mathrm{Mo}\mathrm{Si}}_{2}{\mathrm{N}}_{4}$ MOSFETs. We find that the on-state current in the ${\mathrm{Mo}\mathrm{Si}}_{2}{\mathrm{N}}_{4}$ MOSFETs can be effectively manipulated by the length of gate and underlap, as well as the doping concentration. Very strikingly, we also find that for the n-type devices the optimized on-state currents can reach up to 1390 and 1025 \textmu{}A/\textmu{}m for high-performance and low-power (LP) applications, respectively, both of which satisfy the International Technology Roadmap for Semiconductors (ITRS) requirements. The optimized on-state current can meet the LP application (348 \textmu{}A/\textmu{}m) for p-type devices. Finally, we find that the ${\mathrm{Mo}\mathrm{Si}}_{2}{\mathrm{N}}_{4}$ MOSFETs have an ultralow subthreshold swing and power-delay product, which have the potential to realize high-speed and low-power consumption devices. Our results show that ${\mathrm{Mo}\mathrm{Si}}_{2}{\mathrm{N}}_{4}$ is an ideal 2D channel material for future competitive ultrascaled devices.

Topics & Concepts