Post-stress dual-trap interaction in hot-carrier stressed submicrometer N-channel metal-oxide-semiconductor field-effect-transistors

The interaction of fast and slow interface traps during the post-stress period after maximum substrate current hot-carrier stress in submicrometer n-channel metal-oxide-semiconductor field-effect-transistors (MOSFETs) is investigated. Slow traps, initially present in the fresh device, are increased after the hot-carrier stress. Fast traps, which are negligible in the fresh device, are also generated by the electrical stress. For post-stress times less than 10(5) s, the density of the slow traps remains almost constant while there is a small increase in the density of the fast traps. However between post-stress times of 10(5) to 10(6) s, there is a noticeable decrease in the density of the slow traps which is correlated with an increase in the density of the fast traps. The capture cross-sections of the slow and fast traps tend to converge for post-stress times greater than 10(5) s. The results suggest that the slow traps are possibly evolving into fast traps.