Abstract
We have investigated microstructure evolution of YBa2Cu3O7−y (YBCO) films through the two steps of heat-treatments in the advanced TFA-MOD process, by means of transmission electron microscopy. In the calcination process, precursor films including nanopores are formed with shrinkage of the film after a remarkable increase of the thickness caused by gas generation due to thermal decomposition of metalorganic salts in the starting solution. During the crystallization process, the densification and shrinkage of the film occurs after agglomeration of nanopores and unreacted phase particles such as Y2Cu2O5, CuO and Ba–O–F in the precursor films. Before starting of YBCO epitaxial growth, the densification and shrinkage of the film occurs. The YBCO films are epitaxially grown with remaining the unreacted phase particles in the film, subsequently pores are generated again by a reaction of these unreacted particles to form YBCO accompanying with the volume reduction. In conclusion, it is important to control the densification of precursor films and the coarsening of the unreacted phase particles in the crystallization process, in order to fabricate YBCO final films with fine crystallinity and high IC values.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
