Sputtered BiPbSrCaCuO films on polycrystalline CuO substrates

BiPbSrCaCuO films have been deposited for the first time onto polycrystalline CuO substrates by dc sputtering. The films become superconducting after they are post-annealed in air. Zero resistivity is observed between 38 and 72 K depending on the annealing conditions. The sample showing an onset at 105 K gives an extrapolated zero resistivity at 90 K. The preparation and annealing conditions are described.