Josephson Junction Stuck-At Fault Detection in SFQ Circuits

High reliability is an important requirement for all electronic integrated circuits including superconductive systems. Reliability and yield can be categorized by the failure paths, sequence of faults due to a physical failure, and failure mechanism. Determining the defects and faults is essential to enhance the lifetime of superconductive systems. Josephson junctions (JJs) are the base element of single flux quantum systems. The primary contributions described in this article are a set of JJ-based fault models followed by a methodology for developing high-level fault models. Based on these models, test vectors can be generated to detect the type and/or location of these JJ faults.