Oxidation Behavior of Nanostructure Sputtered Titanium Nitride Thin Films

The oxidation behavior of reactive DC magnetron sputtered TiN thin films was investigated under annealing temperature ranging from 400 to 700oC in the ambient atmosphere using X-ray diffraction, energy dispersive X-ray spectroscopy, and field-emission scanning electron microscopy techniques. The oxidation rate and oxidation activation energy of the films were also calculated from parabolic and Arrhenius relations. The as-deposited film had a polycrystalline TiN structure. After annealing at 450oC, the TiO2 rutile structure was found in the XRD spectra and the relative integrated intensity of the oxide phase increased gradually with temperature. The EDS analysis gave confirmation of XRD patterns, showing the expected increase in O content. Grain growth resulting from grain coalescence occurred through the annealing temperatures. The cross-sectional analysis showed that a very thin dense oxide overlayer was present at 400°C and the oxide thickness increased gradually with temperature. Moreover, the films were fully oxidized into a porous structure after 650oC. The results revealed that the films showed an oxidation rate from 400°C and the oxidation activation energy of films was 156.56 kJ/mol.