Rapid thermal annealing of high T c superconducting thin films formed by metalorganic deposition

Abstract
Thin‐film superconductors of Y‐Ba‐Cu and Yb‐Ba‐Cu have been formed by the nonvacuum method of metalorganic deposition (MOD). The films produced in this manner were homogeneous and free of voids and cracks over large dimensions. A two‐step rapid thermal annealing of the MOD films, in oxygen, at 850 °C for 60 s followed by a second annealing at 920 °C for 30 s enhanced grain growth in the films and reduced the effects of substrate interaction. Preferred epitaxial grain growth, in the high Tc films, with the c axis both perpendicular and parallel to the substrate surface, occurred on 〈100〉 SrTiO3. Both the Y‐Ba‐Cu and Yb‐Ba‐Cu films showed superconducting onset temperatures above 90 K and zero resistance at 86 K.