Growth of TlBa2Ca2Cu3O9-y superconducting films with local biaxial alignment extending up to 5 mm on Ag substrates using a spray-pyrolysis technique

We report on the superconducting properties of TlBa2Ca2Cu3O9-y (T1-1223) thick films grown on smooth and rough Ag substrates. Thallium-free precursor films of the type Ba2Ca2CU3Ag0.37O7 were deposited on Ag substrates using a spray-pyrolysis technique followed by post-thallination in a two-zone furnace. X-ray diffraction (XRD) results showed the presence of c-axis aligned T1-1223 films and some degree of local in-plane texture (often referred to as a colony microstructure). The microstructure of the Ag surface dictates the growth behavior of T1-1223 films. The transport critical-current densities (J(c)) for T1-1223 films grown on smooth and rough Ag substrates were similar to 65,000 A/cm(2) and similar to 37,000 A/cm(2), respectively, at 77 K and zero held. The films grown on smooth Ag substrates were strongly Linked and bad good in-field properties with a J(c) value of similar to 10(4) A/cm(2) at 77 K and 0.5 T.