REVERSIBLE LASER ANNEALING ON YBA2CU3O7-DELTA THIN-FILMS

High-temperature YBa2Cu3O7-delta thin films were patterned by a laser writing technique based on the temperature increase in the focus of a laser beam. The corresponding local increase of the oxygen diffusion v elocity can be employed to write reversibly deoxygenated (semiconducti ng) and reoxygenated (superconducting) patterns, if nitrogen or oxygen , respectively, is chosen as ambient atmosphere. By using different sc an velocities it is possible to decrease or increase T-c and the criti cal current. The influence of the ambient atmosphere, the patterning v elocity and the laser power density on the resulting pattern was inves tigated by different methods, like light microscopy, scanning acoustic near-field microscopy (SNAM), and electrical four-point de measuremen ts. It could be proved that this planar patterning technique has fully reversible properties.