Growth of an Au layer with a thickness in the order of 10 nm on a Yb-Ba-Cu-O substrate

A Yb-Ba-Cu-O/Au structure for an S/N/S (superconductor/normal metal/superconductor) Josephson junction has been successfully fabricated using the bulk Yb-Ba-Cu-O substrate processed by the recently developed PMQ (plasma-arc melting and rapid quenching) method. The coverage of Au layers with a thickness of 30 nm at a substrate temperature of 600°C was confirmed to be almost 100% without any pinholes, which is thin enough to make use of the proximity effect. Similar experiments using Bi₂Sr₂CaCu₂O _x single crystals indicated the possibility of high coverage at even lower substrate temperatures