Effect of relative humidity on morphology of YBCO films prepared by CSD method

YBa2Cu3O7−x (YBCO) films have been prepared on LaAlO3 (1 0 0) substrates by chemical solution deposition using metal trifluoroacetates. The influence of relative humidity in coating circumstance on the morphology of YBCO films was examined by optical microscopy and atomic force microscopy. The crack-free YBCO film was obtained if the relative humidity in coating circumstance was lower than 30%. During the decomposition step, the influences of the water vapor partial pressure and the heating rate within the temperature range from 200 °C to 320 °C were discussed. A smooth YBCO pyrolzed film could be obtained if the suitable water vapor partial pressure and the suitable heating rate within the temperature range from 200 °C to 320 °C were chosen. Furthermore, the smooth crystallized films show a high critical current density of 3 MA/cm2 at 77 K.