A function-fit model for the soft breakdown failure mode

An empirical one parameter-based power law model for the leakage current through one or more soft breakdown spots in ultrathin (<5 nm) gate oxides is presented. Good fit to data can be obtained in nearly five decades of current from 0.5 to 5 V. In addition, it is shown that there exists a slight correlation between the parameters which describe the soft breakdown conduction characteristic and the stressing condition which triggers it.