HOMOEPITAXIAL GROWTH OF YBCO THIN-FILMS ON YBCO SINGLE-CRYSTALS

YBCO films were grown on (001) YBCO single crystal substrates using th e off-axis RF magnetron sputtering method. The interface between the s ubstrate and the film was observed using TEM. The crystal orientation of the film was found to be dependent on the growth temperature. C-axi s oriented films with smooth interfaces and holes on their surfaces we re obtained at 760 degrees C. A-axis oriented films grown at 580 degre es C surfaces, but the interface rather poor. Lattice mismatches occur red atthe interface due to deoxidization and oxidization of the substr ate during the film growth process.