Dry etching properties of TiO2 thin films in O-2/CF4/Ar plasma

Abstract

In this work, the etching properties of titanium dioxide (TiO2) thin film in additions of O-2 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 O-2/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. (C) 2012 Elsevier Ltd. All rights reserved.