Hot-carrier degradation in submicrometre MOSFETs: from uniform injection towards the real operating conditions
An overview is given of the present understanding of the hot carrier degradation problem in submicrometre MOSFETs. First we discuss the degradation mechanisms observed under, for circuit operation, somewhat artificial but well-controlled uniform-substrate hot electron and substrate hot hole injection conditions. Then the more realistic case of static channel hot carrier degradation is treated, and some important process-related effects are illustrated, followed by the behaviour under the most relevant case for real operation, namely dynamic degradation. Finally, the strategies for improving hot carrier reliability and a forecast of the hot carrier reliability problem for sub-0.25 mu m technologies are briefly discussed.