We report on the effect of halide doping on the Aerosol-assisted Chemical Vapour Deposition of tin oxide. Specifically, the importance of precursor interactions is highlighted. A halide exchange reaction involving part substitution of the tin precursor is believed to occur in the solvent; the complex acting as a marker for improved films with improved transparent-conducting properties. Precursor mixtures of butyltin trichloride and potassium halide (X = F, Cl, Br, I) in propan-2-ol were deposited at a substrate temperature of 450 degrees C using air carrier gas. Hall Effect results indicate that fluorine gave the best performing n-type transparent conducting thin films that exhibited high optical transparency (>80% at 550 nm) and resistivity values of 4.9x10(-4) Omega.cm, with charge carrier density and carrier mobility values of 8.85x10(20) cm(-3) and 15 cm(3)/V.s respectively. Such parameters yield high figures of merit. (C) 2012 Elsevier B.V. All rights reserved.