Dependence of Electrical and Optical Properties of Sol-gel-derived SnO2 Thin Films on Sb-substitution

Abstract

In the present work, Sb-doped SnO₂ (ATO) thin films were deposited on Si substrates by spin-coating method and the influence of Sb-doping on surface roughness, structural, optical and electrical properties has been investigated. AFM measurements show that the surface roughness decreases with increasing the Sb-doping concentration up to 5 mol%. XRD results confirm that all prepared ATO films have a tetragonal rutile structure of tin oxide. It has been observed that both the crystallite size and the extinction coefficient decrease with increasing Sb-doping concentration up to 5 mol%, while the refractive index increases with increasing Sb-doping concentration. The electrical resistivity decreases with increasing Sb-doping concentration, and the lowest resistivity obtained is 8.5 × 10^-3 Ω.cm for SnO₂ doped with 7.5 mol% of Sb.