Design and Analysis of Transition Metal Dichalcogenide-Based Feedback Transistor

Abstract

A rise in short channel effects (surface scattering, drain lowering, carrier injection, etc.) in a metal oxide semiconductor field-effect transistor (MOSFET) is worrisome for researchers. Alternate solutions by researchers are tunnel FETs (TFETs), junctionless transistors, and nanowires. Due to random dopant fluctuations, TFETs suffer from various disadvantages like fabrication issues and higher miller capacitances. Junctionless transistors and nanowires do not have fabrication issues but face poor short channel control. Another major unsettled domain is the choice of channel material as silicon suffers significantly in the nanometer regime. Two-dimensional (2D) materials like graphene, transition metal dichalcogenides (TMDCs), and black phosphorus (BP) have provided a solution. Graphene has charge carriers with high mobility, but proposed devices suffer from poor OFF-state current due to the semimetal bandgap of graphene. Although with proper fabrication technique the bandgap can be introduced in the graphene layered structure, it hampers the mobility of charge carriers. In case of BP, mobility increases with an increase in the number of layers, which act as a bottleneck for small-scale devices. In this work, the TMDC material-based feedback field-effect transistor is proposed and analyzed. The feedback transistor provides a steep rise in drain current (IDS ), which provides a very low subthreshold slope; hence, it can be used for high-speed applications. Molybdenum ditelluride (MoTe2) is used as a channel material as it has the lowest bandgap among the TMDC materials, which further aids in high-speed applications. Different device and linearity properties for the proposed device are inspected.