Density functional theory based evaluations of the reactive ion etchin: Process model for TiO₂ (anatase) thin film

We evaluate the reactivity between the surface of the film and gas molecules and determine the optimum gas combinations by calculating the total energy based on the density functional theory. We propose a model for the etching process of titanium oxide thin films. In this model, we consider three specific states, namely, the initial, intermediate and final states. On etching TiO₂ (anatase), we observed that it is more efficient to have fluorine-based reactive gases (e.g. CHF₃) than other considered reactive gases (e.g. CH₄, H₂O) in order to enhance the etching.