Titanium Zirconium Nitride by XPS

Abstract

Titanium zirconium nitride (Ti0.53Zr0.47N) coatings have been deposited on polished steel substrates by dc reactive sputtering in a Sputron (Balzers AG) plasma-beam sputtering apparatus at 200 °C. A thin intermediate layer of TiZr (0.08 μm) was deposited between the substrate and the 2.8 μm thick TiZrN coating. The deposition rate was 12 nm min−1. The partial pressure of nitrogen was 3 × 10−2 Pa, while the total working pressure was 2 × 10−1 Pa. Using a planetary substrate holder with double rotation, thickness and composition uniformity better than 2% were obtained. The average roughness, Ra, of the substrate was <0.04 μm, whereas after the deposition Ra values between 0.06 and 0.08 μm were measured for TiZrN coatings. The XPS measurements were performed in an Escalab 200-X spectrometer (VG Instruments) using nonmonochromatized Al Kα radiation from a twin Mg/Al anode operating at 300 W. The hemispherical energy analyzer was operated in the CAE mode with a constant pass energy of 20 eV. In the present paper the following spectra are presented: survey spectrum, spectra of major elements titanium, zirconium, and nitrogen (Ti 2p, Zr 3d, and N 1s), spectra of minor elements oxygen and carbon (O 1s and C 1s), and valence band spectrum. Spectra were background subtracted using a Shirley method. Peak positions and widths were determined by least squares fitting.