IIRW 2005 Discussion Group Summary: NBTI

The negative bias temperature instability (NBTI) is a pMOSFET reliability problem that is most often observed as a shift in threshold voltage (V) in devices subject to moderate negative gate biases at moderately elevated temperatures. Despite thefirst observations ofNBTI more than 30 years ago, it has not been become a major concern until the pastfew years. The aggravation of NBTI is due to a scaling-induced increase in effective oxidefield as well as the addition ofnitrogen in the gate dielectric. Many models have been proposed to predict the NBTIphenomenon, but a complete understanding ofthe NBTIphenomenon has proved elusive.