Preparation of Rutile TiO2Films by RF Magnetron Sputtering

TiO2films were prepared by rf (13.56 MHz) magnetron sputtering using a mixture of Ar and O2gases. At a total pressure of 2 mTorr, 100% rutile TiO2films were successfully obtained on non heated substrates with rf power of 200 W, while 100% anatase TiO2films were deposited at a pressure of 20 mTorr. Spatial profiles of both emission of excited species and plasma parameters were measured by optical emission spectroscopy (OES) and the Langmuir probe method. At a pressure of 2 mTorr, it was found that high-energy electrons are generated at a certain radial position near the cathode surface where the transverse magnetic field is maximum, and the strong localization of plasma was observed. It was proven that the energetic species impinging on the growing film are responsible for the formation of the rutile phase even if the substrate is at room temperature.