Etching of TiO₂(110) Single-crystal Surface with Aniline for Step Direction Control

After subjecting a hydrofluoric acid treated and annealed TiO2(110) single-crystal substrate to immersion in an ethanol solution of aniline, a uniform step structure in the [001] direction was observed on the TiO2(110) surface without aniline. Since this finding is considered to control the step direction on the TiO2(110) surface, the formed surface was discussed in detail and a model of the step line formation process was proposed.