Tunnel Field-Effect Transistors in 2D Transition Metal Dichalcogenide Materials

TL;DR

This paper investigates the performance of 2D TMD-based TFETs using atomistic quantum transport simulations, highlighting the importance of material choice and device design for achieving high ON-currents and sub-threshold swing below 60 mV/dec.

Contribution

It introduces a full band atomistic simulation approach for TMD TFETs and analyzes the impact of material properties and device parameters on performance.

Findings

High-performance TMD TFETs require optimal material selection.

The choice of TMD material significantly affects device transfer characteristics.

Subthreshold swing and energy-delay are comparable or better than CMOS devices.

Abstract

In this work, the performance of Tunnel Field-Effect Transistors (TFETs) based on two-dimensional Transition Metal Dichalcogenide (TMD) materials is investigated by atomistic quantum transport simulations. One of the major challenges of TFETs is their low ON-currents. 2D material based TFETs can have tight gate control and high electric fields at the tunnel junction, and can in principle generate high ON-currents along with a sub-threshold swing smaller than 60 mV/dec. Our simulations reveal that high performance TMD TFETs, not only require good gate control, but also rely on the choice of the right channel material with optimum band gap, effective mass and source/drain doping level. Unlike previous works, a full band atomistic tight binding method is used self-consistently with 3D Poisson equation to simulate ballistic quantum transport in these devices. The effect of the choice of TMD material on the performance of the device and its transfer characteristics are discussed. Moreover, the criteria for high ON-currents are explained with a simple analytic model, showing the related fundamental factors. Finally, the subthreshold swing and energy-delay of these TFETs are compared with conventional CMOS devices.