The use of an aerosol delivery system enabled fluorine-doped tin dioxide films to be formed from monobutyltin trichloride methanolic solutions at 350-550 °C with enhanced functional properties compared with commercial standards. It was noted that small aerosol droplets (0.3 μm) gave films with better figures of merit than larger aerosol droplets (45 μm) or use of a similar precursor set using atmospheric pressure chemical vapour deposition (CVD) conditions. Control over the surface texturing and physical properties of the thin films were investigated by variation in the deposition temperature and dopant concentration. Optimum deposition conditions for low-emissivity coatings were found to be at a substrate temperature of about 450 °C with a dopant concentration of 1.6 atm% (30 mol% F:Sn in solution), which resulted in films with a low visible light haze value (1.74%), a high charge-carrier mobility (25 cm(2) V s(-1)) and a high charge-carrier density (5.7×10(20) cm(-3)) resulting in a high transmittance across the visible (≈80%), a high reflectance in the IR (80% at 2500 nm) and plasma-edge onset at 1400 nm. Optimum deposition conditions for coatings with applications as top electrodes in thin film photovoltaics were found to be a substrate temperature of about 500 °C with a dopant concentration of 2.2 atm% (30 mol% F:Sn in solution), which resulted in films with a low sheet resistance (3 Ω sq(-1)), high charge-carrier density (6.4×10(20) cm(-3)), a plasma edge onset of 1440 nm and the films also showed pyramidal surface texturing on the micrometer scale which corresponded to a high visible light haze value (8%) for light scattering and trapping within thin film photovoltaic devices.

Zinc oxide (ZnO) thin films are deposited at 400-650 -C onto glass substrates by aerosol assisted (AA)CVD of a zinc acetate [Zn(C 2 H 3 O 2 ) 2 ] solution in methanol. The thin films show high transparency over the visible and infrared regions (80-95%) and a 001 (c-axis) preferred orientation. The surface morphology and crystallographic orientation are dependent on the substrate temperature. The photocatalytic activity of the films is determined using the destruction of stearic acid (SA) by UV irradiation. The rate is monitored via infrared spectroscopy (IRS) and shows appreciable activity, close to that seen for anatase titania, in the films deposited at 650 -C. Water droplet contact angles on both ambient and UV-irradiated ZnO surfaces are determined, and there is seen to be an increase in photoinduced hydrophillicity for all films, with a reduction in contact angle of around 50 -.

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