Analytical modeling of threshold voltage for symmetrical silicon nano-tube field-effect-transistors (Si-NT FETs)

Abstract

In this paper, an analytical model of the threshold voltage for short-channel symmetrical silicon nano-tube field-effect-transistors (Si-NT FETs) is presented. The three-dimensional (3D) Poisson equation in cylindrical coordinates has been solved with suitable boundary conditions to find the surface potential along the channel length. The inversion charge density (Qinv) has been calculated in the channel region of the device in the subthreshold regime of device operation, using the Boltzmann relationship. Subsequently, the calculated inversion charge density (Qinv) has been equated to a threshold charge density (Qth) in order to find the threshold voltage (Vth) expression. The effect of physical device parameters, including the tube thickness, on the threshold voltage and drain induced barrier lowering (DIBL) of the device has been discussed. The model results have been verified with the simulation data obtained by the device simulation software ATLAS. © 2016, Springer Science+Business Media New York.