A Comparison of Fast Methods for Measuring NBTI Degradation

Three fast measuring methods, namely, "on-the-fly," fast direct threshold-voltage (V
_T
) determination, and fast drain-current measurement near V
_T
, are compared. Problems of the different methods are thoroughly discussed, and an analysis of systematic and statistical errors has been done. An example comparing the V
_T
data extracted from the three methods is given. The results help us to understand the root causes for the observed differences in drift curves.