Fluorine-doped tin oxide (FTO) films have been deposited by pulsed DC magnetron sputtering with an Sn target. Various ratios of CF4/O 2 gas were injected to enhance the optical and electrical properties of thefilms. The extinction coefficient was lower than 1:5 × 10 -3 in the range from 400 to 800nm when the CF4/O 2 ratio was 0.375. The resistivity of fluorine-dopedSnO2 films (1:63 × 10-3 Ocm) deposited at 300 °C was 27.9 times smaller than that of undopedSnO2 (4:55 × 10-2 Ocm). Finally, an FTO film was consecutively deposited for protecting the oxidation of indium tin oxide films. The resistivity of the double-layered film was 2:68 × 10 -4 Ωcm, which increased by less than 39% at a 450 °C annealing temperature for 1 h in air.