Sub-10 nm tunneling field-effect transistors based on monolayer group IV mono-chalcogenides

Abstract

The development of air-stable channels with a high on-state current (I_on) is in high demand for the feasible application of TFETs. Monolayer group IV mono-chalcogenides (i.e., GeS, GeSe, SnS, and SnSe), as emerging air-stable atomic-thin semiconductors, are potential channels for sub-10 nm tunneling field-effect transistors due to their high carrier mobility and anisotropic electronic properties. Herein, we investigated the performances of sub-10 nm monolayer (ML) group IV mono-chalcogenide TFETs using ab initio quantum transport simulation. The ML GeSe TFET exhibited the best performance with regards to both high I_on and low leakage current (I_leak) among the four devices, followed by the ML SnSe TFET with a high I_on. The I_on of the optimal ML GeSe TFET with a physical gate length of L_g = 10 nm surpasses the International Technology Roadmap for Semiconductors (ITRS, 2013 Edition) requirements for high-performance (HP) and low-power (LP) devices, simultaneously, and that of the ML SnSe TFET with L_g = 10 nm surpasses the requirement of ITRS HP devices. In combination with our former works, we suggest an E_g of 0.77–1.19 eV and of 0.11–0.15m₀ to search for competitive 2D channels with a high I_on for HP application in TFET devices with a planar homogeneous p–i–n architecture.