Properties of YBaCuO Thin Film Single-Level dc SQUIDs Fabricated Using Step-Edge Junctions

A quantitative comparison study of single-level step-edge junction-based SQUIDs and bicrystal-substrate-based SQUIDs is given. Similar SQUID performance was found in terms of white flux noise level and junction-critical-current-related 1/f noise. Excess current was found in most step-edge devices. Issues related to systems applications, such as magnetic field-induced noise, junction cyclability upon repeated use, and environmental stability of oxide-metal contacts are also discussed. © 1995 IEEE