Impact of intrinsic deformations on the negative differential resistance of monolayer MoS$_2$ ultra-short channel MOSFET

TL;DR

This study investigates how intrinsic deformations like ripples, twist, and wrap affect the negative differential resistance in ultra-short monolayer MoS2 MOSFETs, revealing significant impacts on device performance.

Contribution

It provides a detailed analysis of the effects of intrinsic deformations on NDR behavior in monolayer MoS2 transistors using DFT-NEGF simulations, highlighting the importance of structural imperfections.

Findings

Significant change in NDR peak to valley ratio due to rippling.

Deformations alter the NDR window and electronic properties.

Minor intrinsic deformations can substantially impact device characteristics.

Abstract

In this work we present a study on the impact of various intrinsic deformations like ripples, twist, wrap on the electronic properties of ultra-short monolayer MoS2 channels. The effect of deformation (3-7o twist or wrap and 0.3-0.7 buckling amplitude) on a 3.5 nm planar monolayer MoS2 MOSFET is evaluated by the density functional theory and the non-equilibrium Green`s function (DFT-NEGF) approach. We study the channel density of states, transmission spectra and the ID-VD characteristics under the varying conditions, with focus on the negative differential resistance (NDR) behavior. Our results show significant change in the NDR peak to valley ratio (PVR) and the NDR window with such minor intrinsic deformations, especially with the rippling.