Theoretical study of single and dual gate MoS2 based TMDFET by varying oxide thickness and channel length

Abstract

In this paper, we have performed the theoretical study of single and dual gate MoS 2 based TMD Field Effect Transistor (TMDFET). The different performance characteristics of TMDFET such as ON state current (ION), leakage current (IoFF), and IoN/IoFF ratio can be done by using different gate oxide thickness and channel length. The Molybdenum disulphide (MoS 2 ) is used as channel material for both single and dual gate TMDFET device. For the calculation of ION and IoFF characteristics, the Non Equilibrium Greens Function (NEGF) has been used by solving the Poisson's equation. The IoFF (leakage) current is calculated at gate-source voltage (VGS) =0 by keeping drain-source voltage (VDS) fixed at 0. 5V and also calculated the on state current (ION) at different values of VGS for oxide thickness varying from 1nm to 3nm in step of 0.5nm and channel length from 5nm to 11nm in step of 2nm range. Other performance characteristics with reduced short channel effect like subthreshold slope are also calculated for both single and dual gate TMDFET. It has been observed that the performance of dual gate TMDFET is better in case of ON state current (ION), and reduced leakage current (IoFF) than single gate TMDFET. The effect of short channel is also minimum in dual gate device over single gate device.