Growth and characterization of c-axis oriented YBa(2)Cu(3)O(7-x)/PrBa(2)Cu(3)O(7-x) bilayers

We report on the preparation and characterization of YBa(2)Cu(3)O(7-x)/PrBa(2)Cu(3)O(7-x) bilayers onto (100) SrTiO(3) substrates. The samples have been prepared by sequential de sputtering processes in high oxygen pressure from stoichiometric targets. The structural characterization of the of YBa(2)Cu(3)O(7-x) and PrBa(2)Cu(3)O(7-x) films and of the bilayers has been performed by means of X-ray diffraction. The Scanning Electron Microscopy analysis has showed that the film surfaces are flat and free of precipitates. A detailed study of the interfaces has been performed by Transmission Electron Microscopy analysis. The electrical resistivity measurements showed for the YBa(2)Cu(3)O(7-x) films sharp superconducting transitions at 91.5 K and critical current density of about 10(6) A/cm(2) at 77 K, while for the PrBa(2)Cu(3)O(7-x) films a semiconductor-like behavior has been observed