On the Frequency Dependence of Bulk Trap Generation During AC Stress in Si and SiGe RMG P-FinFETs

The impact of channel Germanium content (Ge%) and gate stack Nitrogen content (N%), on bulk trap generation (ΔVoT) time kinetics is studied by using DC and AC stress at different voltage (VGSTR) and temperature (T) in RMG HKMG Si and SiGe p-FinFETs. It is shown that ΔVOT magnitude is dependent on frequency (f), which can make the resulting threshold voltage shift (ΔVT) dependent on f for some stress conditions. The f dependence of ΔVOT and ΔVT becomes stronger at higher Ge% and weaker at higher N%. The ΔVT time kinetics is modeled for DC and AC stress under different stress conditions (V
_GSTR
, T and f) and for different processes (Ge%, N%).