Simple and accurate modeling of double-gate FinFET fin body variations

Abstract

This paper presents a simple and accurate model for determining I on and Ioff of a double-gate FinFET with varying gate fin shapes. Simulations show that gate fin shape variation results in significant changes in the leakage and driving capability of the device. We perform TCAD simulations of double-gate FinFET structures in order to analyze the effect of the gate fin body thickness (Tsi) variation on the electrical properties of the device. The thicknesses of the source and drain side are found to have different effects on the device. A simple model is proposed using the threshold voltage change due to the thickness variation along the gate fin. Simulation results show that the models match well with Ion and Ioff within 1.3% and 4.8% errors, respectively. In addition, we propose an optimal fin body shape to reduce the leakage current while providing a similar driving current to that in the nominal FinFET.