Impact of Process Variation on MIM Capacitor Lifetime

MIM capacitor lifetime depends strongly on dielectric thickness. If there is significant spread in thickness this can make the TDDB lifetime estimation overly pessimistic. This can be countered by adapting the lifetime expression to include a metric for thickness. We have analyzed TDDB data in conjunction with measured capacitance density. This approach allows for more accurate lifetime estimates. It also facilitates process optimization choices.