Manufacturing pattern development for the Alpha 21164 microprocessor

Functional test patterns play a key role in the test strategy of many microprocessors. This paper describes the process of creating and fault grading an initial set of functional test vectors. The fault simulation results are used to identify design verification test (DVT) hard faults and to guide additional test development. Moreover, this paper details the effectiveness of test creation heuristics and the role functional tests play in identifying defective devices. This process has been used to improve the outgoing quality levels of Digital's second generation Alpha microprocessor.