We present micro corona - Kelvin data acquired on ZrO2/Al2O3/ZrO2 (ZAZ) dielectric stacks in the active capacitor cell areas of advanced DRAM production wafers. Specifically, we compare micro - SASS (Self Adjusting Steady State) voltage data measured on patterned wafers to similarly acquired data on blanket ZAZ dielectric stacks. From this comparison, we formulate a model that interprets active area micro - SASS voltage as being proportional to the ZAZ dielectric stack capacitance. Validation of the method and accompanying model is made through measurement of a production baseline that demonstrates sensitivity to various process deviations. Further validation is achieved through comparison of in-line active cell area micro - SASS data to End - of - the - Line Electrical Parametric Measurement Capacitance and Breakdown Voltage data. We also demonstrate that the method, which includes corona charging and measurement on the active device areas, does not adversely impact final device yield.
