Epitaxial YBa2Cu3O7minus;dgr;/NdAlO3/YBa2Cu3O7minus;dgr;hyphen;trilayers were grown by sputtering from stoichiometric targets. The YBa2Cu3O7minus;dgr;(YBCO) films were deposited by dchyphen;magnetron sputtering. For the NdAlO3films, rfhyphen;magnetron sputtering was used. The individual YBCO films revealed criticalhyphen;current densities up to 3times;106A/cm2at 77 K. The bilayer and trilayer structures were characterized by xhyphen;ray diffraction, Rutherford backscattering spectroscopy, and transmission electron microscopy (TEM). The channel yield khgr;minof the YBCO film on top was 15percnt; for aninsitudeposited trilayer. The epitaxial growth of the subsequent layers was proved by crosshyphen;sectional TEM. Although the NdAlO3layer contained misoriented grains, the top YBCO layer grows in single orientation over these areas. Preliminary electrical measurements show that NdAlO3is a useful insulating dielectric for microelectronic applications.
展开▼
