Characterization of the YbBa2Cu3O7-y and YBa2Cu3O7-y thin superconducting films prepared by chemical solution deposition on MgO(001) substrate

Thin superconducting films of the YbBa2CU3O7-y (Yb123) and YBa2CU3O7-y (Y12 3), prepared by post-deposition annealing of the metal naphthenates gels sp in-coated on MgO(001) substrate, have been characterized by cross-sectional high-resolution electron microscopy and X-ray diffraction. It was found th at the c-axis Yb123 films were epitaxially grown on the MgO(001) substrate at the temperature range from 700 degrees C to 775 degrees C in a gas mixtu re containing Ar and O-2 with the oxygen partial pressure of p(O-2) = 10(-4 ) atm. In contrast to the Yb123 films, it was found that Y123 films could b e derived at a wider temperature range from 750 degrees C to 950 degrees C. Randomly oriented Y123 films were also grown on the MgO(001) substrate bes ides the majority of in-plane c-axis oriented growth.