Proof and quantification of dynamic effects in hot-carrier-induced degradation under pulsed operation conditions

To investigate their relevance in hot-carrier degradation under pulsed operation conditions, different physical properties of the Si/SiO/sub 2/ system were studied. The authors prove the existence of effects traceable to the slow hopping conduction of holes in the oxide, to charge detrapping, and to trapped hole neutralization under alternating electron-hole injection conditions. Transient effects attributable to interface traps were not observed. The authors evaluated the importance of these properties for a modern submicron process under typical digital logic operation conditions. Their impact on lifetime considerations based on quasistatic estimations remains rather limited in the case of the n-channel transistor. In the p-channel transistor, however, lifetime can be significantly improved due to the detrapping of trapped electrons. As in digital CMOS applications, hot carrier degradation occurs during switching transients only and no significant dynamic enhancement was found. The lifetime of a device in a circuit is thus improved by two orders of magnitude as compared to that inferred from static stressing alone.<>