FABRICATION AND CHARACTERISTICS OF VERTICALLY STACKED NBCN MGO/NBCN JOSEPHSON-JUNCTIONS WITH THIN INTERMEDIATE ELECTRODES/

Vertically stacked NbCN/MgO/NbCN Josephson junctions with thin interme diate electrodes (2 nm similar to 11 nm) have been fabricated on a sil icon wafer in a computer-controlled sputtering system. The tunneling c haracteristics of fabricated junctions have been evaluated as function s of the number of stacks and thickness of intermediate electrodes d. As a result, it has been found that the energy gap for intermediate el ectrodes reduced with d linearly depending on 1/d. The junction qualit y parameter R-SG/R-N gradually decreased with d.