Process Qualification

Abstract

This paper offers a practical approach to process qualification based on estimating the impact on the fraction nonconforming and the sensitivity of the nonconformance rate to changes in the mean or standard deviation of the process. The methodology makes certain assumptions regarding the magnitude of the changes that might be expected in the process parameters and then computes the effect that these changes might be expected to have on the nonconformance probability and its variability. If the impact is within acceptable limits, then the process is considered robust enough to be released to production.