Dual-curvature cavity for improved p-type FinFET performance

This work presents a new dual-curvature cavity that enables p-type transistor electrical I-on-I-off 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 (I-on) through enabling larger SiGe source/drain with deeper cavity while it minimizes the penalty of drain leakage (I-off ) increase though keeping the additional cavity away from the channel In this work, devices with dual-curvature cavity demonstrated 3%-6% I-on-I-off performance improvement for different threshold voltage flavors in a mature 14 nm production line.