Effect of photomask pattern shape for a junction counter-electrode on critical current uniformity and controllability in Nb/AlO(sub x)/Nb junctions

The effect of photomask pattern shape for a counter-electrode on critical current (I(sub c)) uniformity and controllability in Nb/AlO(sub x)/Nb junctions is evaluated. Although no difference is found in the (I(sub c)) uniformity between square and OPC junctions, the OPC junctions exhibited smaller shrinkage in junction size than the square junction.