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 sputt ering was investigated. In order to improve the superconductivity,oxyg en should be activated. For this purpose, we developed a hollow cathod e activation system to deposit superconducting YBCO films. When the cu rrent of hollow cathode nas 100mA, we obtained the Tc of 87K for YBCO film on (100) SrTiO3 substrate at 730 degrees C. YBCO targets with var ying 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 deposi t various materials such as insulator, the YBCO-Y2O3-YBCO trilayer str uctures were also succecfully formed.