A new statistical model for fitting bimodal oxide breakdown distributions at different field conditions

摘要

A new statistical model for fitting competing Weibull distributions is introduced. This model takes into account that capacitors with process-induced defects can also fail intrinsically if they survive the extrinsic breakdown mode. It is shown that this model in combination with a field acceleration law for intrinsic and extrinsic breakdown, can be implemented in a maximum likelihood fitting algorithm, allowing to fit a complete set of breakdown data obtained at different field conditions simultaneously in one single calculation.