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Thin films with mostly (Hg,Tl) 1Ba2Ca3Cu2O8+ δ [(Hg,Tl)-1223] phase have been fabricated by radio frequency magnetron sputtering of precursor films and post-annealing method. The doping of a small amount of thallium in the film is helpful to the formation of the three-layer CuO2 compound. These films have a highly oriented structure with the c-axis perpendicular to the film surface. Resistivity measurements show that the films after annealing at 300 °C for 1 h in O2 have the superconducting transition temperature of Tc (onset)=133 K and Tc (zero)=127 K. Scanning electron micrographs of the film reveal platelike micrometer-size grains coalesce to cover the substrate surface.