Analytical modelling for surface potential of dual material gate overlapped-on-drain TFET(DM-DMG-TFET) for label-free biosensing application

Abstract

This article presented the first-ever 2D analytical model for the surface potential of dual material gate overlapped-on-drain TFET (DMG-TFET) device for label-free biosensor application using dielectric modulation technique. The use of two different metal work functions for the gate (ϕM1<ϕM2) impacts the device’s surface potential to increase tunneling width at the secondary tunneling junction to enhance the device sensitivity compared to single material gate device. This model takes into account the effect of changing the dielectric constant value, location, and percentage of fill factor of the target biomolecules on the surface potential of the device. The parabolic approximation of surface potential is used for solving the 2D-Poisson’s equation by applying suitable boundary conditions. The analytical surface potential results are verified with the simulation result using the SILVACO Atlas tool.