DEPOSITION PRESSURE EFFECTS ON THE LASER PLUME OF YBA2CU3O7-DELTA

The control of the preferential orientation in oxide superconducting films, which is generally done by deposition temperatures, was achieved by choosing the oxygen pressures during the deposition. Time-resolved optical observations of the laser plume were carried out at the same time with the film deposition. Upon increasing the oxygen pressure, the velocities of the emissive species ablated from the target were decreased. The kinetic energy effects of the ablated species on the film orientation are discussed, and the orientation change can be qualitatively understood by a surface migration model as well as the case of the deposition temperature dependence.