HOT-CARRIER-INDUCED DEGRADATION OF N2O-OXYNITRIDED GATE OXIDE NMOSFETS

Measurement of long term electrical characteristics of N2O-oxynitrided gate oxide NMOSFET's revealed that the role of nitrogen-rich layer as a blocking barrier for molecular hydrogen diffusion plays a dominant role in the reduced device degradation. A two-step model was proposed, in which the release of hydrogen species and their reaction with the trivalent silicon atoms are main factors for hot-carrier-induced-degra dation. Hot carrier immunity of the NMOSFET's was also found to origin ate partially from tile small increase of both the effective barrier h eight for electron injection and the interface trap creation energy du e to negative charged nitrogen-rich layer.