ION-BEAM SPUTTER-DEPOSITION PROCESS FOR Y1BA2CU3O7-DELTA THIN-FILM STRUCTURES

Ion-beam sputter deposition (IBS) has been developed to a fully oxygen -compatible technology for growth of complex oxides, such as Y1Ba2Cu3O 7-delta (YBCO) thin films. The IBS system consists of an rf-plasma ion source with molybdenum grids for sputtering, a dc-plasma electron sou rce for space charge compensation, stoichiometric YBCO and NGO targets , a beam chopper with BaO2, Cu, and Nd blades for stoichiometry contro l, and an ECR-oxygen-plasma source for in situ film oxidation and phot oresist removal. Due to its complexity the IBS process is fully comput er-controlled, A salient feature of IBS is the excellent crystallograp hic and morphological properties of thin (100)/(010)- and (103)-orient ed YBCO films on SrTiO3 (STO) and NdGaO3 (NGO) substrates. Sharp inter faces and good superconducting properties render this technology feasi ble for the fabrication of SIS-ramp-junction SQUID's.