PROJECT TITLE:

Scan Chain Masking for Diagnosis of Multiple Chain Failures in a Space Compaction Environment - 2015

ABSTRACT:

Diagnosis is extremely vital to ramp up the yield during the integrated circuit manufacturing method. It reduces the time to promote and merchandise cost. Limited observability due to check response compaction negatively affects the diagnosis procedure. When multiple chains, mapped to one compactor, fail, diagnosis becomes very difficult. The procedure is even additional sophisticated as a result of when a circuit fails the flush check, not all the patterns are applied. Only a few of the patterns are applied and also the observed responses are used to diagnose the faulty chains. In this project, we have proposed an efficient masking strategy that can be terribly useful for diagnosis of scan chains when multiple scan chains fail. The proposed strategy uses the redundancy in fault detection by the test patterns and masks scan chains in such a approach that enough information can be supplied with small increase in test pattern count. A new tester architecture that will choose and apply only those patterns having enough information for diagnosis has additionally been proposed. Diagnostic resolution and first hit index achieved by our method are very close to their ideal values, that validate the applicability of our approach.