Thick YBa2Cu3O7 films by post annealing of the precursor by high rate e-beam deposition on SrTiO3 substrates

High rate evaporation techniques were used to deposit Y, BaF2, and Cu precursor films onto SrTiO3 single crystal substrates at rates in excess of 10 nm/s. Y and Cu were deposited by electron beam (e-beam) heating and thermal heating was used for BaF2. Post deposition annealing was used to form 3 mu m thick c-axis aligned YBa2Cu3O7 films on the SrTiO3 substrates, Critical current densities 1.8 x 10(5) A/cm(2) at 1 T (H parallel to c) and 77 K were achieved. The films were nominally stoichiometric and were post-deposition annealed in a humidified reduced oxygen atmosphere at 725-800 degrees C. These results indicate that the so-called BaF2 post annealing process can be one of several possible candidate methods for production of thick YBa2Cu3O7 coatings for large scale applications. (C) 1998 Published by Elsevier Science B.V. All rights reserved.