Dry etching properties of TiO2 thin films in O2/CF4/Ar plasma

In this work, the etching properties of titanium dioxide (TiO2) thin film in additions of O2 at CF4/Ar plasma were investigated. The maximum etch rate of 179.4 nm/min and selectivity of TiO2 of 0.6 were obtained at an O2/CF4/Ar (=3:16:4 sccm) gas mixing ratio. In addition, the etch rate and selectivity were measured as a function of the etching parameters, such as the RF power, DC-bias voltage, and process pressure. The efficient destruction of the oxide bonds by ion bombardment, which was produced from the chemical reaction of the etched TiO2 thin film, was investigated by X-ray photoelectron spectroscopy. To determine the re-deposition of sputter products and reorganization of such residues on the surface, the surface roughness of TiO2 thin film were examined using atomic force microscopy.

► We investigated the etching properties of the TiO2 thin films in additions of O2 at CF4/Ar (=16:4 sccm) plasma.
► The efficient destruction of the oxide bonds by ion bombardment of the chemical reaction was investigated by XPS analysis.
► The surface morphology and roughness was examined using AFM.