Post-stress interface trap generation: a new hot-carrier induced degradation phenomenon in passivated n-channel MOSFET's

Abstract
Passivated n-channel MOSFETs can show significant increases in interface trap density after termination of hot carrier stress. The dependence of this poststress interface trap generation mechanism on various parameters was investigated. A simple model based on the generation of both positive and neutral hydrogen by detrapped holes injected during stress can account for all observed phenomena. For accelerated lifetime experiments under AC conditions for which hole injection occurs, an apparently non-quasistatic behavior was observed that can be readily explained by this mechanism. Prediction of device lifetime under AC conditions, based solely on DC experiments, is then straightforward.