Preparation of Bi-based high-T-c superconducting films from methacrylate solutions

Bi2Sr2CaCu2Ox superconducting films containing minor amounts of Bi2Sr2Ca2Cu 3Ox were prepared by spray pyrolysis of methacrylate solutions on LaAlO3 su bstrates. The best superconducting properties (T-c similar or equal to 80 K , Delta T-c similar or equal to 10 K) were shown by the films annealed at 8 50 degrees C, which consisted mainly of platelike crystallites with a high degree of [001] orientation. The composition, content, and morphology of th e calcium strontium cuprates and oxides present as impurity phases were fou nd to correlate with the annealing temperature and film thickness.