Semi-Classical Study of n-MOS Inversion Layer

Abstract

We study the energy band diagram, surface electric field , charge density and static current voltage (C-V) characteristics of a metal-oxide-semiconductor (MOS) capacitor by self consistently solving the one dimensional Poisson's equation and semi-classical charge density. Also analytical expressions are derived under depletion approximation and they are compared with the self-consistent simulation results. Analytical expressions of different levels of approximation are used to study the current-voltage (IV) characteristics, sub threshold current, and quasi-Fermi potential along the channel of an n-channel metal-oxide semiconductor field effect transistor (MOSFET). Analytical and simulation results of MOS capacitor match well at relatively low biases. The current in MOSFETs with different approximation match pretty well at low bias and the parabolic approximation underestimate the current at higher biases.