Formation of epitaxial YBCO thin films by ex-situ processing of a polymerized complex
High T/sub c/ and J/sub c/ YBa/sub 2/Cu/sub 3/O/sub 7-x/ (YBCO) thin films have been formed by ex-situ processing of a spin coated organic sol-gel precursor based on a polymerized complex. To form the precursor we have reacted metal cations with a chelating organic acid, then formed polyesterified complexes through reaction with a polyhydroxy alcohol. This method permits a simple, cheap and reliable route to the fabrication of YBCO films. The value of J/sub c/ achieved for the film deposited onto a LaAlO/sub 3/ [100] substrate at 77 K under a zero field is routinely as high as 0.25 MA/cm/sup 2/ with T/sub c,zero/ of 90.6 K.