Process Variation Study for Silicon Nanowire Transistors

This paper examines the sensitivity of silicon nanowire transistors to process variations. Silicon nanowire MOSFETs are effective in controlling short channel effects, but at the same time suffer from threshold voltage degradation due to the quantum confinement effect. In this study we have investigated the effects on the device characteristics of process variations due to body thickness, gate length and gate dielectric thickness. The results have been compared with previous results for the FinFET and the differences quantified. The nanowire MOSFET is found to exhibit significantly less short channel effects relative to a comparable FinFET structure, but to have a larger threshold voltage variation with the diameter at a diameter less than 4 nm.