Dual-curvature cavity for improved p-type FinFET performance

Abstract

This work presents a new dual-curvature cavity that enables p-type transistor electrical Ion–Ioff performance improvement in FinFET technology. A dual-curvature cavity is a conventional ball-shaped cavity with an additional smaller cavity at the bottom formed through further pushing down the Fin and spacers in the gate canyon. This new cavity design benefits on-state current (Ion) through enabling larger SiGe source/drain with deeper cavity while it minimizes the penalty of drain leakage (Ioff) increase though keeping the additional cavity away from the channel. In this work, devices with dual-curvature cavity demonstrated 3%–6% Ion–Ioff performance improvement for different threshold voltage flavors in a mature 14 nm production line.