Emerging oxide degradation mechanisms: Stress induced leakage current (SILC) and quasi-breakdown (QB)

The reliability of thin oxides is a primary concern for the qualification o f advanced CMOS, DRAMs and non volatile memory technologies. With the scali ng down process the thickness of active dielectrics in CMOS, DRAMs and memo ry devices has steadily been reduced during the past years. The reduction o f the oxide thickness has given rise to the onset of new phenomena for the viewpoint of reliability such as stress induced leakage current (SILC) and quasi-breakdown (QB). This paper intends to present a brief review of these emerging degradation processes which affect the reliability of ultra-thin oxides. The main characteristics and the physics underlying the SILC and QB will be discussed and illustrated with recent experimental results obtaine d on advanced technologies featuring thin gate dielectrics.