Effect of the laser sputtering parameters on the orientation of a cerium oxide buffer layer on sapphire and the properties of a YBa2Cu3Ox superconducting film

The effect of the laser sputtering parameters on the crystal properties of CeO2 buffer layers grown on a (1 (1) under bar 02) sapphire substrate and on the properties of superconducting YBa2Cu3Ox thin films are investigated. It is shown that (100) and (111) CeO2 growth is observed, depending on the sputtering conditions. A buffer layer with the desired unidirectional orientation can be obtained by varying the heater temperature, the pressure in the chamber, and the energy density of the laser beam at the target. (C) 1999 American Institute of Physics.