Topography of anatase TiO2 film synthesized on LaAlO3(001)

The surface of an anatase titanium dioxide (TiO2) film grown on LaAlO3(001) was observed using noncontact atomic force microscopy (NC-AFM). After cleaning with cycles of argon ion sputtering and annealing in vacuum, (1 × 4)- and (1 × 5)-reconstructed terraces appeared. In addition to the terraces, the sputter-annealed surface included many agglomerations. The presence of Tin+ () shown by x-ray photoelectron spectroscopy indicates that the agglomerations are due to TiOx () species. Limited replenishment of oxygen by the substrate and the low diffusivity of the Tin+ to the substrate are possible causes for the generation of the TiOx.