Performance investigation of a semi‐junctionless type II heterojunction tunnel field effect transistor in nanoscale regime

Abstract

In this work, the electrical characteristics and impact of physical and structural parameters on the performance of a novel heterojunction GaAs 0.1 Sb 0.9 -InAs semi-junctionless tunnel field effect transistor (SJTFET) is demonstrated. Unlike the conventional p-i-n tunnel field effect transistor, the n-channel SJTFET is a p + -p + -n structure having similar doping profile for the source and channel regions. First, all the structural and physical parameters are set to their initial values, and then, one parameter is varied to investigate its variation effect on the performance of SJTFET. Standard deviation and mean value of subthreshold swing, off-state and on-state current manifests that the performance of SJTFET is more sensitive to the gate workfunction, source-channel doping density and gate oxide thickness, respectively, in comparison with other structural parameters. The two-dimensional variation matrix of off-state current, on-state current and threshold voltage is calculated as a function of gate workfunction and source-channel p + doping density for determining an optimum value for the source-channel doping concentration and gate workfunction. Due to the n-p + drain-channel junction, the tunnel barrier in the off-state mode can be increased into the drain region, providing low off-state current in the ultra-scaled device and makes this device become less sensitive to short channel effects.