PLASMA INTERACTION PROCESSES DURING THE PULSED-LASER DEPOSITION OF SUPERCONDUCTING THIN-FILMS

Superconducting YBa2Cu3O7-x thin film growth by electron cyclotron res onance plasma-assisted pulsed laser ablation is studied. Resistivity a nd X-ray diffraction measurements: were employed in analyzing plasma i nduced reaction processes during both the deposition and cooling stage s of film preparation. It is demonstrated that the crystal structure i s determined by the oxygen kinetics during the deposition process whil e the superconducting phase is formed through enhanced plasma oxidatio n during the cooling stage. Direct and glancing incidence plasma irrad iation of the thin Rims surface was carried out. Under direct oxygen p lasma irradiation, varying the average ion energy between 18 and 8 eV leads to a direct correlation between the ion energy and the resulting thin film crystal structure. Oxygen ion induced lattice defects and d amage are identified as the limiting factor in producing high quality superconducting thin films at low substrate temperatures.