Compact model for short channel symmetric doped double-gate MOSFETs

Abstract

A new compact model for currents in short channel symmetric double-gate MOSFETs is presented which considers a doped silicon layer in the range of concentrations between 1014 and 3×1018cm−3. The mobile charge density is calculated using analytical expressions obtained from modeling the surface potential and the difference of potentials at the surface and at the center of the Si doped layer without the need to solve any transcendental equations. Analytical expressions for the current–voltage characteristics are presented, as function of silicon layer impurity concentration, gate dielectric and silicon layer thickness, including variable mobility. The short channel effects included are velocity saturation, DIBL, VT roll-off, channel length shortening and series resistance. Comparison of modeled with simulated characteristics obtained in ATLAS device simulator for the transfer characteristics in linear and saturation regions, as well for as output characteristics, show good agreement within the practical range of gate and drain voltages, as well as gate dielectric and silicon layer thicknesses. The model can be easily introduced in circuit simulators.