SUPERCONDUCTING YBA2CU3O7 FILMS DEPOSITED ON SI(100) SUBSTRATES WITH CEO2 BUFFER LAYERS BY LASER ABLATION

Superconducting YBa2Cu3O7 (YBCO) thin films have been deposited on Si (100) substrates with CeO2 buffer layers by laser ablation. The films were characterized by X-ray diffraction (XRD), secondary ion mass spectrometry (SIMS) and four-point electrical resistivity. Secondary ion mass spectrometry results indicate low interdiffusion between Si, CeO2 and YBCO. The best YBCO films are textured with c-axis perpendicular to the substrate and their resistance exhibits a normal state metallic behavior with zero resistance around 84 K. The crystalline and electrical properties of YBCO films were related with the substrate temperature. A minimum substrate temperature is necessary to deposit good superconducting YBCO films. Moreover, there is a maximum temperature to obtain c-orientation, although the electrical properties are not degraded yet.