Analytical 2D Modeling of Surface Potential and Threshold Voltage for Lightly Doped Substrate NMOS

Abstract

Reducing the device dimensions leads to scaling of various parameters like junction depth, supply voltage and gate oxide thickness and results to the variation of threshold voltage. Threshold voltage variations can cause serious design problems. So threshold voltage can be adjusted by various ways which is the most important parameter of the MOSFET. This paper depicts the analytical modeling and simulation of Metal Oxide Semiconductor Field Effect Transistor (MOSFET). The expression for potential at source and drain ends and threshold voltage has been derived and the theoretical values are compared with simulated values. From simulation results from SILVACO TAD tool, threshold voltage of 0.22V is achieved at a work-function of 4.12eV.