Ab initio quantum transport simulation of the sub-1 nm gate-length monolayer and bilayer α-MoTe2 field-effect transistors

Abstract

Two-dimensional semiconducting α-MoTe₂ is a promising channel material for the field-effect transistors (FETs). Recently, the performance limit of the sub-5 nm gate-length n- and p-type monolayer and multilayer α-MoTe₂ transistors has been reported theoretically. However, this material is still unexplored for the ultra-short (sub-1 nm) gate-length n- and p-type metal–oxide semiconductor field-effect transistors (MOSFETs). Here, we performed ab initio quantum transport simulation of the 0.34 nm gate-length n- and p-type MOSFET based on the monolayer (ML) and bilayer (BL) α-MoTe₂ for high-performance (HP) and low-power (LP) applications. The proposed n-type ML α-MoTe₂ transistor achieves an on-state current (I_on) of 396 μA μm⁻¹ for HP and 183 μA μm⁻¹ for LP, and intrinsic delay time (τ) of 0.334 ps for HP and 1.075 ps for LP. It also exhibits a power delay product (PDP) of 0.071 fJ μm⁻¹ for HP and 0.060 fJ μm⁻¹ for LP, thereby satisfying the International Technology Roadmap for Semiconductors (ITRS) requirements for both HP and LP applications. Unfortunately, the p-type ML and the n and p-type BL α-MoTe₂ transistors fail to achieve the required I_on to meet the ITRS standard for HP and LP applications. This research extends the potential application of the ML α-MoTe₂ from the sub-5 nm gate-length FETs to the sub-1 nm region.