Performance Comparison between Asymmetric Polycrystalline Silicon Gate and TiN Gate Fin-Shaped Field Effect Transistors

Abstract

We report our numerical study on the device performance of an asymmetric polycrystalline silicon (poly-Si) gate fin-shaped field effect transistor (FinFET) and FinFET with TiN metal gate structure. Our numerical simulation revealed that the asymmetric poly-Si FinFET structures and TiN gate FinFET structures exhibits a superior VT tolerance to the conventional FinFET structure with respect to the variation of fin thickness. For instance, the VT tolerance of the asymmetric poly-Si FinFET were 0.02 V while TiN gate FinFET exhibited 0.015 V tolerance for the variation of the fin thickness of 5 nm (from 30 to 35 nm) while the conventional FinFET demonstrates 0.12 V fluctuation for the same variation of the fin thickness. Our numerical simulation revealed that threshold voltage (VT) can be controlled within - 0.1 to + 0.5 V by the varying of doping concentration of the asymmetric poly-Si gate region from 1.0×1018 to 1.0×1020 cm-3.