Fault coverage and defect level estimation models for partiallytestable MCMs

摘要

The authors propose a simple and efficient mathematical model forndesigners to estimate fault coverage for partially testable multichipnmodules (MCMs). This model shows a relation between fault coverage, testnmethodology, and the fraction and distribution of design for testabilityn(DFT) dies in MCMs. Experimental results show that the proposed modelncan efficiently predict the fault coverage of a partially testable MCMnwith less than 5% deviation. An automatic DFT dies deployment algorithm,nbased on the genetic algorithm and the model is proposed to helpndesigners to obtain a fault coverage as close to the upper bound ofnfault coverage as possible. Two defect level estimation models, whichnrelate fault coverage and manufacturing yield for measuring the testnquality of MCMs under equiprobable and non-equiprobable faults,nrespectively are also formulated and analysed to support theneffectiveness of the model