The effect of oxygen-containing reagents on the crystal morphology and orientation in tungsten oxide thin films deposited via atmospheric pressure chemical vapour deposition (APCVD) on glass substrates.
Thin films of monoclinic WO3 and WO(3-x) have been synthesized by atmospheric pressure chemical vapour deposition from WCl6 and three oxygen containing precursors; water, ethanol and ethanoic anhydride. A wide variation in the colour, crystal morphology and preferred orientation of the films was observed, depending on the chosen oxygen source. In particular contrast were the films formed from WCl6 and ethanol, which were blue and had needle-like crystallites, and those formed from WCl6 and water, which were yellow and had hexagonal shaped crystallites. Studies were also undertaken to form films from WCl6, ethanol and water simultaneously, in which the ratio of ethanol to water was varied, and this led to films in which the crystal morphology and orientation could be controlled.
Hyett
Geoffrey
G
Christopher Ingold Laboratory, University College London, 20 Gordon Street, London, United Kingdom WC1H 0AJ.
Blackman
Christopher S
CS
Parkin
Ivan P
IP