On the efficiency of stress techniques in gate-last n-type bulk FinFETs

► Stressors have different efficiency in planar nFETs and n-FinFETs. ► Gate-last leads to strong enhancement of CESL efficiency on planar and Fin nFETs. ► A gate fill can lead to 10% mobility enhancement for narrow gate-first n-FinFETs. ► In gate-last transistors, using a tensile gate fill degrades n-FinFET mobility.