Development of a simulator for transition metal dichalcogenide channel field effect transistors incorporating quantum mechanical effects

Abstract

In recent years, Transition Metal Dichalcogenides (TMDs) have gained broad interest as the channel materials of Field Effect Transistors (FETs) after the development of fabrication and growth of two dimensional (2D) materials. Suitable bandgap, dangling bond free interfaces and atomic scale thickness make TMD materials, like Molybdenum disulphide (MoS2) and Tungsten diselenide (WSe2), attractive for switching and logic devices. A robust simulator with quantum mechanical effects of 2D FETs will be a promising addition to the existing literature and will pave the way to explore the sub-10nm technology in near future. In this thesis work a computationally efficient simulator considering the quantum mechanical effects of TMD FETs has been developed by using only MATLAB. Schrödinger-Poisson equations are solved self-consistently using material parameters extracted from literature.The numerical simulator has been used to study the transport performance of a monolayer WSe2 FET structure with 20 nm of channel length. The performance analysis revealed excellent on and off state performances of the device with an impressive ON/OFF current ratioof ~〖10〗^6, on current of 547 μA/μm, and sub-threshold swing of 85.27mV/dec.To show the compatibility with circuit level simulation performance, analysis of monolayer MoS2 channel TMD FETs has also been presented. Finally, the optimal structure with greatest performance for the device has been proposed.