Modeling techniques and tests for partial faults in memory devices

It has always been assumed that fault models in memories are sufficiently precise for specifying the faulty behavior. This means that, given a fault model, it should be possible to construct a test that ensures detecting the modeled fault. This paper shows that some faults, called partial faults, are particularly difficult to detect. For these faults, more operations are required to complete their fault effect and to ensure detection. The paper also presents fault analysis results, based on defect injection and simulation, where partialfaults have been observed. The impact of partialfaults on testing is discussed and a test to detect these partialfaults is given.