Transient effects and characterization methodology of negative bias temperature instability in pMOS transistors

We report a new effect - relaxation of pMOSFET degradation due to negative bias temperature instability (NBTI). "Apparent" NBTI degradation is reduced ("recovered") by as much as 30-50% after stress interruption, which can increase device lifetime by a factor of 10-30. Some problems associated with extrapolation of degradation with respect to time and stress voltage are also discussed.