Structural and Oxidation Behavior of Nanocomposite TiCrN Thin Films

Abstract

The structural and oxidation behavior of nanocomposite titanium chromium nitride (TiCrN) thin films has been investigated by using x-ray diffraction (XRD), energy dispersive x-ray spectroscopy (EDS), and field emission scanning electron microscopy (FE-SEM). The TiCrN thin films were deposited on Si substrates by using the reactive DC magnetron sputtering technique from the Ti-Cr mosaic target. After that, the as-deposited thin films were annealed in the air at 500 - 900°C for 2 h. The XRD results showed that the formation oxidation of anataseTiO2, rutile-TiO2, and Cr2O3 which diffraction peak appear from 500°C. The relative intensity of these oxide peaks varied with the annealed temperatures. By observing from FE-SEM, the aggregation of the grain increased with the annealing temperature. The cross-sectional results showed that the thin dense oxide overlayer occurred at 700°C and the oxide thickness increased gradually with the annealing temperature. Meanwhile, underneath the TiCrN grain grew above 700°C and become more void structure after annealing at 700°C. The dramatically increase of the oxygen content was found at 700°C and the evolution of Ti, Cr, N, and O with different elements compositions at various annealing temperatures were investigated from the EDS technique. The oxide layer obviously grows inward indicating the oxidation of TiCrN thin films belongs to inward oxidation. The oxidation rate of the films was increased with the increase of annealing temperature. The activation energy of the oxidation as evaluated by the Arrhenius-type relation was 168 kJ/mol.