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

摘要

In this paper, we have performed the theoretical study of single and dual gate MoS₂ based TMD Field Effect Transistor (TMDFET). The different performance characteristics of TMDFET such as ON state current (I_ON), leakage current (I_OFF), and I_ON/I_OFF ratio can be done by using different gate oxide thickness and channel length. The Molybdenum disulphide (MoS₂) is used as channel material for both single and dual gate TMDFET device. For the calculation of I_ON and I_OFF characteristics, the Non Equilibrium Greens Function (NEGF) has been used by solving the Poisson's equation. The I_OFF (leakage) current is calculated at gate-source voltage (V_GS) = 0 by keeping drain-source voltage (V_DS) fixed at 0. 5 V and also calculated the on state current (I_ON) at different values of VGS for oxide thickness varying from 1 nm to 3 nm in step of 0.5 nm and channel length from 5 nm to 11 nm in step of 2 nm 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 (I_ON), and reduced leakage current (I_OFF) than single gate TMDFET. The effect of short channel is also minimum in dual gate device over single gate device.