Failure analysis for full-scan circuits

We present a complete system for failure analysis of full-scan circuits. A novel scheme has been proposed to handle multiple faults up to a certain extent by ranking the faults according to the likelihood of being present in the defective part. The user can interactively recompute the suspect fault list by changing some parameters. If the suspect fault list is large, we generate new test patterns to distinguish the faults in the suspect list. User can iterate over a defective part several times until the suspect fault list is reasonably small. Then each suspect site is probed using E-beam. This tool is integrated into design environment of LSI Logic Corporation and produced good results when applied on a few industry circuits.