00.511.51e-131e-121e-111e-101e-91e-81e-71e-61e-51e-40.001fresh (log axis)after BTI stress (log axis)subthreshold slope26 mV/decadegate-source voltage Vgs (V)drain current Id (A), log scaleTransfer curve: log for the off state, sqrt-linear for the thresholdsqrt(Id) (x1e-2 A^0.5), linear scale012345sqrt(Id), fresh (right axis)sqrt(Id), stressed (right axis)fresh (log axis)after BTI stress (log axis)sqrt(Id), fresh (right axis)sqrt(Id), stressed (right axis)