Structural perfection of Y-Ba-Cu-O thin films controlled by the growth mechanism

For crystalline advanced materials, such as the high transition temperature oxide superconductors, the growth of defect-free crystals is often the most sought after desideratum because it opens the doors to fundamental studies and the development of practical applications. We report the observation of YBa 2Cu3O7-x(123) thin films having unprecedented structural perfection, at temperatures near 700°C on [001] LaAlO 3. The film's c axis is in the surface plane, unlike films grown at higher temperatures. This orientation has important advantages for device applications and fundamental studies. The Tc,0 is only 70 K, presumably due to oxygen deficiency caused by thermal stresses; if so, it should be possible to raise the Tc,0 by relieving these stresses.