A comparison of different spray chemical vapour deposition methods for the production of undoped ZnO thin films

Two different methods of spray chemical vapour deposition have been used to grow ZnO thin films on glass substrates from zinc acetate solution over the temperature range 400 °C to 550 °C. The first of these is named InfraRed Assisted Spray Chemical Vapour Deposition (IRAS-CVD). This method uses intense IR radiation to heat not only the substrate but also the gaseous species entering the reactor. The second method is a more conventional approach known simply as ultrasonic spray CVD, which utilises IR lamps to heat the substrate only. By way of comparing these two approaches we present data obtained from contact angle measurements, crystallinity and mean crystallite size, photoluminescence, electrical and optical properties. Additionally we have examined the role of annealing within the IRAS-CVD reactor environment.