Channel layer-dependent optimization of on-state current and subthreshold swing of MoS2 TFET

This paper presents a comparative analysis among two different layers (monolayer and multilayer) of molybdenum disulfide (MoS₂) channel based n-type tunnel field-effect transistor (TFET) to optimize on-state current and subthreshold swing ( Sth S) by tuning different device parameters such as oxide thickness, doping concentration, screening length, dielectric strength as a function of gate voltage and electric field. Two closed-form analytical models of tunneling current and Sth S are used for MoS₂-based TFET due to the superior performance of MoS₂ as a channel material for post-silicon and beyond-graphene technology. Additionally, band-to-band tunneling (BTBT) mechanism results in higher on-state current and lower Sth S in TFETs compared to MOSFETs. The present study reveals that it's quite hard to get the best-optimized results for the on-state current and Sth S simultaneously, that is, there is a tradeoff between them. The whole optimization process is carried out by varying two parameters and variables concurrently in order to have more accurate results.