SCANNING-TUNNELING-MICROSCOPY OF LASER-DEPOSITED YBA2CU3O7 THIN-FILMSON Y-STABILIZED ZIRCONIA SUBSTRATE

The surface morphology and growth mechanism of c-oriented YBa2Cu3O7 th in films deposited on Y-stabilized zirconia substrate by laser deposit ion has been investigated with scanning tunneling microscopy. Both scr ew dislocation and layered island growth processes took place. Surface features such as screw dislocation, steps, subgrain boundaries, holes , and troughs were present, suggesting that they may act as pinning si tes for flux lines. A thin layer of nonsuperconducting material with a thickness of a few angstroms is seen on the surface of the film.