We present characteristics of overdamped Josephson junctions consisting ofNb/AlOx/Al/AlOx/Nbstructures. The junctions were fabricated using a well-developedNb/AlOx/Nb-junction technology and showed well-defined Josephson characteristics at 4.2 K. The characteristic voltageVc[the product of the critical currentIcand the effective normal resistanceRn(eff)] of junctions, which determines high-frequency performance of the junction, was in the range of 0.1–0.5 mV, and the critical current densityJcin the range of102–104 A/cm2.Maximum-to-minimum variations inIcover a wafer were±4&percent;for junctions withVc=0.15 mVand±13&percent;for junctions withVc=0.5 mV.©1997 American Institute of Physics.