As-Deposited Superconducting Ba2YCu3O7-y Films Using ECR Ion Beam Oxidation

Abstract
Superconducting Ba2YCu3O7-y films have been grown epitaxially on (100) and (110) SrTiO3 substrates at a substrate temperature of 600°C using an evaporator combined with an ECR ion source for oxidation. Three molecular beams (BaF2, Y and Cu) were deposited simultaneously under the oxygen ion-beam (50 eV) bombardment. The as-deposited films showed zero resistance at 80–82 K with thicknesses between 200 and 700 nm on both (100) and (110) substrates. The oxygen ion beam was very useful to oxidize the metal sufficiently, to dissociate the BaF2 molecules and to lower the substrate temperature.