Monte Carlo simulation of electron transport properties in extremely thin SOI MOSFET's

Abstract

Electron mobility in extremely thin-film silicon-on-insulator (SOI) MOSFET's has been simulated. A quantum mechanical calculation is implemented to evaluate the spatial and energy distribution of the electrons. Once the electron distribution is known, the effect of a drift electric field parallel to the Si-SiO/sub 2/ interfaces is considered. The Boltzmann transport equation is solved by the Monte Carlo method. The contribution of phonon, surface-roughness at both interfaces, and Coulomb scattering has been considered. The mobility decrease that appears experimentally in devices with a silicon film thickness under 20 nm is satisfactorily explained by an increase in phonon scattering as a consequence of the greater confinement of the electrons in the silicon film.