Boundary layers of oxide superconductors films pasted on Al2 O3, MgO, SrTiO3 and YSZ

Energy-dispersive X-ray analysis, wavelength-dispersive X-ray analysis, and scanning microscopy examinations have been performed for annealed Y-Ba-Cu-O(YBCO) and Bi-Sr-Ca-Cu-O(BSCCO) films which will be adopted for future superconducting devices. Relatively thin films pasted on various substrates and cross sections were tested. The influence of the annealing on the substrate and superconducting films has been investigated. The results show the formation of boundary layers of intermediate products, which consists of Ba compounds between the YBCO layer and substrate (Al₂O₃, SrTiO₃, and ZrO₂) and Sr and Bi compounds between the BSCCO layer and substrate (SrTiO₃, MgO, and ZrO₂)