DYNAMIC EFFECTS IN HOT-CARRIER DEGRADATION RELEVANT FOR CMOS OPERATION

We describe different dynamic degradation effects in n- and p-MOSFETs as they are clearly proven and generally accepted to date. It turns ou t that they are connected with time constants in the oxide and at the interface and that time constants related to the device operation are too short to be relevant in this context. The effects are detrapping o f fixed charges, the slow movement of holes in the oxide, an enhanced- degradation effect caused by alternating voltage conditions, during dy namic stress, and a post-stress interface state formation effect in ni tride passivated n-MOSFETs. Furthermore, we discuss the relevance of t hose effects, under different operation conditions, finding that the f ast non-stationary effects are of little significance. Only the ''slow '' effects, with time constants of seconds and above, play a role in r eliability issues of MOSFETs.