A new smart Vth-extraction methodology considering recovery and mobility degradation due to NBTI

In the recent literature several measurement methods were introduced to characterize the V_th-degradation of NBTI considering the recovery phenomenon. To our knowledge each method has a severe problem or at least a significant disadvantage. Either there are long delay times, the accuracy is not satisfactory or it is not possible to implement the method with customary equipment. A compromise is to do a one point measurement in the subthreshold region and calculate V_th based on the assumption that the subthreshold slope is not or only marginally affected by NBTI. In this paper we disprove the universality of this assumption. V_th determination using a one point measurement can lead to imprecise values. This extraction method disregards mobility degradation after NBTI impacting V_th, which we have clearly obtained in our measurements. We introduce a new smart V_th extraction methodology offering both shortest possible delay times with customary equipment and consideration of mobility degradation effects.