Preparation of Y-Ba-Cu-O films by ion-beam sputtering with a hollow cathode oxidation

Deposition of as-grown high Tc superconducting films by ion beam sputtering was investigated. In order to improve the superconductivity, oxygen should be activated. For this purpose, we developed a hollow cathode activation system to deposit superconducting YBCO films. When the current of hollow cathode was 100mA, we obtained the Tc of 87K for YBCO film on (100) SrTiO3 substrate at 730°C. YBCO targets with varying composition were used and resulting YBCO films were examined by X-ray diffraction. The result showed optimum target to obtain pure YBCO film was Ba and Cu rich one (YBa2.2Cu4Ox). IBS are suitable to deposit various materials such as insulator, the YBCO-Y2O3-YBCO trilayer structures were also succecfully formed.