Influence of test techniques on soft breakdown detection in ultra-thin oxides

This paper presents soft breakdown (SBD) measurement results on ultra-thin oxides and shows that constant current stress and constant voltage stress SBD measurements do not yield equivalent time-to-failure results. Correlation issues that exist between the two techniques include the percentage of detected SBD events, the post-SBD noise and current–voltage ( I–V) behavior. To understand the differences between these two measurement techniques the effect of stress source power on the SBD event is examined. It is found that limiting the available source power during stress significantly impacts the detection and post I–V behavior of the SBD event.