Thin YBaCuO films on CuAl alloy substrate

Films were obtained using a laser sputtering technique. The targets to be sputtered were YBa ₂Cu ₃O _{7 - x} ceramics and the substrate was a foil of 0.4 mm thick Cu-5% Al alloy. Sputtering was performed in an oxygen medium at a pressure of 1.7 Pa. The substrate temperature was varied from 700 to 850°C. The films obtained were 0.5 - 0.6 μm thick and were non-superconducting at the substrate temperature of 700°C. For samples with J_c ≥ 10 ² A cm ^-2 the transition to the superconducting state began at 91 K and ended in the range 70-80 K. The critical current density value changed within a wide range, as a function of the structural state of the film.