Poisson mixture yield models for integrated circuits: A critical review

Yield models for semiconductor devices are often derived from Poisson mixtures, the specific model being dependent on the distribution assumed for the density of point defects. Presented here is a review of the development of such yield models, including two new models obtained by using the Rayleigh and the inverse Gaussian as mixing distributions. The various models are compared and some general properties of yield functions for any Poisson mixture are derived. The concept of reference region is introduced and its implication for yield modeling is discussed.