Superconducting TI,Ba,Ca,Cu,O,, thin films with T, (p = 0) up to 121 K were successfully prepared via the deposition of a BaCaCuO precursor (by laser ablation or sputtering) and thallium diffusion under 1 atmosphere of air. Instead of a short annealing time at high temperature, we use a prolonged annealing time (up to 60 hours) at lower temperature (80&815'C). The films obtained with this procedure are generally good in morphology, highly oriented and exhibit a critical current density, J, , of about 1-2 x l o 5 A cm-'on MgO(100) and u p to 1.5 x 1 0 6 A cm-* on LaAI,(lOO) at 77 K. Both T, and J, values reported here are comparable to the best TI-2223 films prepared by the pseudo-one-step process.

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