Dynamic recovery of negative bias temperature instability in p-type metal–oxide–semiconductor field-effect transistors

An unexpected physical phenomenon—dynamic recovery of negative bias temperature instability (NBTI)—is reported. NBTI degradation in p-type metal–oxide–semiconductor field-effect transistors is significantly (by ∼40%) reduced after stress interruption. NBTI recovery dynamics includes a very fast transient (seconds time scale) followed by a slow (tens of minutes) transient, which tends to saturate. Under subsequent application of stress bias, the degradation quickly returns to its previous state. Thus, apparent NBTI degradation includes permanent and reversible components. NBTI degradation and device lifetime depend strongly on the measurement procedure and equipment due to these relaxation phenomena, which should be taken into account in analyzing the results of NBTI measurements.