Effect of gate dielectric on electrical parameters due to metal gate WFV in n-channel Si step FinFET

Abstract

This work reports the statistical impact of dielectric constant (k) of gate dielectric materials on various electrical parameters in step-FinFET (fin field-effect transistor) and conventional FinFET (C-FinFET) due to the gate metal work function variability (WFV). 3D technology computeraided design simulations showed that several performance parameters are more affected by the WFV in C-FinFET than in step-FinFET. It was observed that the fluctuation of parameters like subthreshold swing (σSS), on current (σIon), and off current (σIoff) are noticeably affected by dielectric materials. However, for both the structures, there is no significant variation in the threshold voltage (σVT) with variation in k values for varying grain size.