Nonlinear characteristics of Weibull breakdown distributions and its impact on reliability projection for ultra-thin oxides

We report nonlinear characteristics of Weibull time-to-breakdown distributions and non-Poisson area scaling behavior observed on ultra thin oxides. We develop a numerical model to quantitatively account for these effects in the context of current modulation due to oxide thickness variations. It is found that without proper treatment of current modulation effect, the use of Weibull slopes at higher failure percentiles can lead to erroneous and pessimistic reliability projection.