Fabrication of NiO/Bi2Sr2CaCu2Ox hetero-structure by a DC hollow cathode sputtering

NiO was attempted to be used as a barrier material for high-Tc tunnel junction. BSCCO films were deposited on MgO(100) or SrTiO3(110) using a dc hollow cathode sputtering. As-grown superconducting BSCCO film was obtained at Ts = 700°C on MgO, and was c-axis oriented. The crystallinity of NiO films, which were deposited on c-axis oriented BSCCO films at various temperature, were investigated. NiO deposited at the temperature above 600°C was dominantly (100) oriented. The nonlinearity was observed in the I - V characteristics of Ag/NiO(4nm)/BSCCO junction.