The influence of annealing atmosphere on the material properties of sol-gel derived SnO2:Sb films before and after annealing

SnO2 films with and without Sb doping were prepared by the sol-gel spin-coating method. Material properties of the SnO2 films with different Sb contents were investigated before and after annealing under O-2 or N-2. When SnO2 films are annealed under N-2 or O-2, the resistivity decreases with increasing annealing temperature, which may be related to the increased crystallinity and reduced film defects. The intensity of SnO2 peaks for both O-2- and N-2-annealed films increases as the annealing temperature increases. Small nodules are revealed on the surface of SnO2 films after annealing in N-2 or O-2 atmospheres, and some voids are present on the surface of N-2-annealed SnO2 films. After doping with Sb, the resistivity of SnO2 films after annealing in O-2 is greater than that of N-2-annealed SnO2 films. The surface morphology of SnO2 films incorporating different molar ratios of Sb after annealing are similar to that of as-spun SnO2 films with adding Sb. There were no voids found on the surfaces of N-2-annealed SnO2:Sb films. In addition, the peak intensity of SnO2:Sb films after O-2-annealing is higher than those films after N-2-annealing. The chemical binding states and Hall mobility of the high-temperature annealed SnO2 films without and with adding Sb are also related to the annealing atmospheres. This study discusses the connection among the material properties of the SnO2 films with different Sb contents and how these properties are influenced by the Sb-doping concentration and the annealing atmospheres of SnO2 films. (C) 2012 Elsevier B.V. All rights reserved.