Fabrication and properties of Nd-Ba-Cu-O/Pr-Ba-Cu-O/Nd-Ba-Cu-O ramp-edge junctions

We present recent results on the fabrication process of NdBa/sub 2/Cu/sub 3/O/sub 7-/spl delta// (NBCO) ramp-edge junctions with a PrBa/sub 2/Cu/sub 3/O/sub 7-/spl delta// (PBCO) barrier by pulsed laser deposition (PLD). We also describe the fabrication of high T/sub c/ Superconductor-Normal metal Superconductor (SNS) junctions in an edge geometry with integrated ground planes and insulators. The process incorporates five layers which includes an integrated high T/sub c/ ground plane with a low /spl epsiv//sub r/ interlevel dielectric layer of CeO/sub 2/ deposited by Metal Organic Chemical Vapour Deposition (MOCVD). We have used YBa/sub 2/Cu/sub 3/O/sub 7-/spl delta// (YBCO) single crystals as a groundplane. It was confirmed that NBCO layers could be incorporated in the multilayer structure without substantial degradation. Process modifications necessary to reach our fabrication goals are outlined.