Determination of Reliability from Ramped Voltage Breakdown Experiments; Application to Dual Dielectric MIM Capacitors

Ramped voltage breakdown experiments were used to derive the dependence of life-time, τ(v), on the applied voltage for Ta2O5-Si3N4 dual dielectric capacitors. Techniques previously described allowed for recognition of defective capacitors, which break down early, and for the effect of trapping of injected carriers, which retards the breakdown. It is there. ore possible to determine τ(v) for charge-free nondefective capacitors--a quantity of interest for reliability. For nonoptimistic reliability projections, τ(v) must be obtained over a range in voltage so that log τ(v) versus v exhibits, at the lower portion of that range, an upward concavity. Projections thus obtained were verified in a life-test.