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Biaxially aligned cerium oxide (CeO2) and yttria stabilized zirconia (YSZ) films were deposited on Ni-based metal (Hastelloy C276) substrates held at room temperature using ion beam assisted (IBAD) magnetron deposition with the ion beam directed at 55° to the normal of the film plane. In addition, we achieved, room-temperature epitaxial growth of CeO2 by bias sputtering to form biaxially aligned CeO2/YSZ bilayers. The crystalline structure and in-plane orientation of films was investigated by x-ray diffraction techniques. Both the IBAD CeO2 and YSZ films, and the CeO2/YSZ bilayers have a (111) pole in the ion beam direction.

Superconducting YBa2Cu3O7−x thin films are prepared in situ by on-axis dc magnetron sputtering from a single stoichiometric target. The magnetron uses an unbalanced magnetic field configuration to eliminate resputtering effects, and high quality thin films on MgO (100) substrates are realized with excellent reproducibility. The target is sputtered in Ar/O2 mixture at a fixed partial pressure ratio pAr/pO2= 15:1. We report on the growth and properties of films deposited (a) as a function of the total sputtering pressure pt (1–100 Pa) at fixed substrate heater temperature Ts=740 °C, and (b) as a function of Ts (600–860 °C) at fixed pt=42 Pa. Epitaxial c-axis thin films are obtained over a wide range of deposition conditions (Ts≥700 °C, pt≥30 Pa). These films have superconducting transition temperatures Tc=86–90 K, critical current densities Jc77≥106 A cm−2, and resistance ratios R300/R100=2.0–3.1.

Absiract-High quality reproducible junctions are mandatory in the construction of high-?', RF and DC SQUIDs using YBazCu307-, thin films. In this paper, we describe two methods used to produce step-edge junctions on MgO substrates suitable for SQUID devices. In both processes a titanium mask has been used to produce a straight, well defined step which assists, in minimizing the occurrence of multiple junctions. We describe two ionmilling processes which produce differently connected stepedge junctions as indicated by SEM micrographs, I-V and I,-B characteristics. Predictable relationships between the ratio of the film thickness t o step height and the junction critical-current density are demonstrated; these enable the creation of step-edge junctions with appropriate values of I, for particular SQUID designs.