Reaction of Ba2YCu3O6.9 films with yttria-stabilized zirconia substrates

Abstract
Degradation of Ba2YCu3O6.9 films on yttria‐stabilized zirconia substrates is shown to proceed by barium depletion from the film and barium zirconate formation. This process is accompanied by a decrease in the temperature of zero resistivity and ultimately produces Y2Cu2O5 and CuO. BaZrO3 is, however, found to be inert to Ba2YCu3O6.9 at 950 °C. Use of a truly chemically inert substrate material may permit extended heat treatment of films without degradation due to substrate interactions.