Microstructure and Superconducting Properties of Doped Bi,Pb-2223 Thin Films Fabricated by Sputtering and Annealing

The microstructure and superconducting properties of doped thin films of the superconductor (Bi,Pb)
₂
Sr
₂
Ca
₂
Cu
₃
O
_x
(Bi,Pb-2223), fabricated by sputtering using doped Bi,Pb-2223 targets and subsequent annealing, were investigated. The aim of this paper was to assess the feasibility of increasing the critical current density (J
_c
) for Bi,Pb-2223 tapes and to address the weak response of Bi,Pb-2223 to magnetic fields via doping with various elements. The transition temperature (T
_c
) for a pure Bi,Pb-2223 film was determined to be 86.8 K, while doped Bi,Pb-2223 films exhibited higher values, with T
_c
of 95.0 K for an Hf-doped film. I
_c
-B-T-angle transport data indicated that J
_c
for an Hf-doped Bi,Pb-2223 film was much higher than that for an undoped film at all angles at 77.3 K and 0.5 T.