Nanocrystalline SnO2 thin films prepared by anodization of sputtered Sn thin films.

Thin films of SnO₂ are prepared by anodic oxidation of Sn on glass substrates. The surface topography of the anodic films is consistent with the original Sn films, indicating that the oxidation process primarily takes place perpendicularly along the Sn particles. As-prepared anodic SnO₂ thin films possess an amorphous SnO₂ phase at the surface, followed by an unoxidized thin layer of Sn between the SnO₂ film and the substrate. With increasing annealing temperature, the residual Sn layer decreases until it disappears at 400 °C, and the amorphous SnO₂ becomes nanocrystalline. The mobility of the as-prepared anodic SnO₂ films is less than 0.1 cm₂/(V s), but the annealed films have a mobility range of 1.6-₂.₂ cm₂/(V s). [ABSTRACT FROM AUTHOR]