Real time semiconductor process excursion monitor

Semiconductor process excursions may be monitored by fabricating functional circuitry on a plurality of semiconductor devices and then testing the functional circuitry of the plurality of semiconductor devices using a sequence of test patterns. A cumulative failure curve may be determined that has points of discontinuity based on results of testing with the sequence of test patterns. A point of discontinuity magnitude at a selected location in the cumulative failure curve may be compared to an expected discontinuity magnitude. Process excursion analysis may be indicated when a point of discontinuity magnitude exceeds an expected magnitude threshold.