The physical mechanisms of defect clustering and its correlation to yield model parameters for yield improvement

The superposition principle is used to analyze faults of different mechanisms. The sum of individual cluster coefficients is approximately equal to the cluster coefficient for all mechanisms combined. A regression analysis of empirical data is used to demonstrate the concept. The actual fault density is compared to the model fault density and shows excellent agreement. The application of this model to actual chip yields is shown to be more accurate but also contain information about the relative number of fault generating mechanisms for the mask level of interest in the process. Future applications and areas of further work are given.<>