Surface morphologies and electrical properties of antimony-doped tin oxide films deposited by plasma-enhanced chemical vapor deposition

Antimony-doped tin oxide (ATO) films were deposited on Corning glass 1737 substrates by a plasma-enhanced chemical vapor deposition (PE-CVD) technique using a gas mixture of SnCl4–SbCl5–O2–Ar. Electrical properties and surface morphologies of these films were studied by varying the deposition temperature, input gas ratio, R[=(PSbCl5/PSnCl4)], and RF power. The PE-CVD method effectively enhanced the deposition rate and also improved the surface roughness of the deposit compared with thermal CVD. The antimony doped tin oxide films which had relatively good electrical properties were obtained at a deposition temperature of 450°C, an input gas ratio of R=1.12, and a RF power of 30 W. In addition, the studies on the morphological development of the films by AFM analysis suggested that higher input gas ratio and lower deposition temperature led to a decrease in the surface roughness of the deposited films.