Rapid thermal annealing of YBaCuO thin films deposited on SiO₂ substrates

Ag/Cu/BaO/Y2O3/Ag layered structures have been formed using electron-beam evaporation on SiO2 substrates, and post-annealed by rapid thermal annealing at different temperatures. After a 960 °C 15-s anneal, the film showed a superconducting onset temperature of 93 K and a zero resistance at 79 K. With a lower-temperature anneal, the film exhibited metallic behavior. On the other hand, for a higher-temperature anneal, silicon was found to diffuse into the film as observed by Auger depth profiling. The Si out-diffusion degraded the superconducting properties of the film.