Hole trap effect on time-dependent-dielectric breakdown (TDDB) of high-voltage peripheral nMOSFETs in flash memory application

In this work, the TDDB mechanism in high-voltage nMOSFETs with high-density of pre-existing defects in the gate oxide is investigated. In contrast to the traditional nMOSFETs with very few defects in the gate oxide, the additional hole trapping through the stress-induced generated defects close to the gate side not only induce longer fail time, but also induce smaller voltage acceleration factor and lower 10-year V
_max
.