Influence of sintering conditions in the preparation of acetate-based fluorine-free CSD YBCO films using a direct sintering method

In this paper, an intensive study is performed to elucidate the link between sinter temperature and sinter atmosphere as processing parameters in YBCO film formation, starting from an aqueous fluorine-free AWAT CSD precursor. Moreover, the results are linked to the reaction mechanism behind this non-fluorine approach. This resulted in a partial oxygen versus temperature diagram containing different zones giving rise to specific YBCO properties. It is observed that sinter temperature and sinter atmosphere should be judiciously chosen to obtain high quality superconducting films. Under a 200 ppm O2 atmosphere, highly textured YBCO films are obtained when sintering took place at 815 °C giving rise to an inductive Tc,onset of 92 K and a Jc-value up to 1.1 MA cm−2. Moreover, this paper gives a clear indication that the formation of a liquid phase strongly enhances the epitaxial growth.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slideHighlights► Highly c-axis oriented YBCO films were grown starting from aqueous CSD precursors. ► Using a direct sintering method, a short high temperature treatment was obtained. ► The link between synthesis, structure and superconducting properties was elucidated. ► Epitaxial growth is enhanced by liquid phase intermediates.