Characteristics of YBa2Cu3Oy coated conductors prepared by in-plume method

In order to increase a deposition rate, we prepared YBCO films on metal substrate and SrTiO3 single crystal substrate by in-plume PLD method and compared superconducting properties, deposition rate and composition ratio with those of films prepared by the conventional PLD method. Typical Tc of the films prepared by the conventional PLD on the IBAD-MgO substrates were 89.7 K and typical Jc were about 3.0 MA/cm2 at 77 K in self-field. On the contrary those of films by the in-plume PLD were 87.9 K and Jc were about 0.9 MA/cm2. The deposition rate of the in-plume PLD was 2 μm/hour in thickness which was about twice higher than that of the conventional PLD. A reason of the low superconducting properties would be off-stoichiometry within the film, especially Ba deficient composition. To improve the composition ratio of the films, we used off-stoichiometric YBCO target and investigated the superconducting properties. We were able to improve the composition of the films. However Jc values were not improved. The primal reason why the Jc values were low would be an outgrowth within the films.