Hot carrier degradation and time-dependent dielectric breakdown in oxides

An overview is given of our present understanding of the main degradation mechanisms acting during hot carrier and high field stress of gate oxides. A brief summary of the most important charge injection mechanisms is given, followed by a description of the damage generated under uniform charge injection. Then the degradation under more realistic operating conditions of channel hot carrier injection is reviewed, including the lifetime determination methods and the strategies to improve the hot carrier lifetime. The most important methods of oxide breakdown testing are described, as well as the basics of oxide breakdown statistics. The change of this statistics with decreasing oxide thickness, and the impact on the reliability is illustrated. The most important breakdown models and field acceleration models are reviewed as well.