A new waveform-dependent lifetime model for dynamic NBTI in PMOS transistor

We report a detailed study on dynamic NBTI (DNBTI/sub inv/) for inverter-alike digital waveforms, with reference to static NBTI (SNBTI). A simple phenomenal DNBTI lifetime model is obtained for this waveform, to facilitate the extraction of DNBTI/sub inv/ lifetime from conventional SNBTI lifetime determination (with a one-time model parameter calibration) for wide range of waveform. frequency, duty cycle, voltage and temperature. Furthermore, the application of the model to the lifetime estimation of circuits with multiple operation modes is also discussed. For an effective annealing of defect to be taken place, at least 10/sup -8/ s of device off time is required. Finally, it is found that inverter-like waveform suffers the most severe DNBTI degradation as compared to other waveforms and attributed to transient HCI effect.