Fluorine-doped tin oxide (FTO) films have been deposited by pulsed DC magnetron sputtering with an Sn target. Various ratios of CF4/O2 gas were injected to enhance the optical and electrical properties of the films. The extinction coefficient was lower than 1.5×10(-3) in the range from 400 to 800 nm when the CF4O2 ratio was 0.375. The resistivity of fluorine-doped SnO2 films (1.63×10(-3) Ω cm) deposited at 300 °C was 27.9 times smaller than that of undoped SnO2 (4.55×10(-2) Ω cm). 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) Ω cm, which increased by less than 39% at a 450 °C annealing temperature for 1 h in air.