NIOBIUM NITRIDE ALUMINUM NITRIDE SUPERCONDUCTOR INSULATOR MULTILAYERSAND TUNNEL-JUNCTIONS/

Niobium nitride/aluminium nitride multilayers have been fabricated usi ng dc reactive magnetron sputter deposition. By careful optimization a suitable set of deposition conditions has been achieved under which b oth high quality superconducting and insulating layers may be fabricat ed. This has allowed automation of the deposition process to fabricate multilayers by simple computer control of substrate position and shut tering. Deposition onto a range of single crystal and amorphous substr ates has given a range of different crystal structures. We have measur ed the transport properties of these multilayers as a function of supe rconductor and insulator layer thickness in order to study the interla yer coupling, and have fabricated stacked superconductor - insulator - superconductor junctions.