SUPERCONDUCTING ND1.85CE0.15CUO4-Y THIN-FILMS AND HETEROSTRUCTURES ONSAPPHIRE

Superconducting Nd1.85Ce0.15CuO4-y (NCCO) thin films have been made on Yttria-Stabilized Zirconia(YSZ) buffered sapphire. The films are epit axially grown and highly in-plane oriented. X-ray diffraction shows th e c-axis of the film normal to the surface of the substrate. The width of reeking curve is 0.2 degrees and the RBS channeling yield is 9%, i ndicating high crystallinity of the film. Cross-sectional transmission electron microscopy images reveal a sharp interface between NCCO and YSZ, The microwave surface resistance of NCCO films on YSZ buffered sa pphire at 9.6 GHz was measured and a value of so mu Omega (at 4.2 K in zero de magnetic field) was obtained, which is comparable to Y1Ba2Cu3 O7-y (YBCO) films at the same reduced temperature, A trilayer structur e of YBCO/SrTiO3/NCCO on YSZ buffered sapphire has been fabricated wit h all layers oriented, in which both the YBCO and NCCO layers are supe rconducting.