Mechanical properties and oxidation behavior of Ti-Si-N films prepared by plasma-assisted CVD

Comparative studies of the mechanical and oxidation properties of TiN and T i-Si-N films were carried out in this work. The Ti-Si-N films were deposite d on high-speed steel and silicon wafer substrates by a plasma-assisted che mical vapor deposition (PACVD) technique using a gaseous mixture of TiCl4/S iCl4/N-2/H-2/Ar. The Ti-Si(similar to 7 at.-%)-N film showed an increased h ardness value of similar to 3400 HK (kg mm(-2)) in comparison with the undo ped TiN film. The Ti-Si(similar to 7 at.-%)-N film also showed much improve d anti-oxidation properties compared with the pure TiN film. The glass-like oxide layer on the surface of the Ti-Si-N film was formed and retarded fur ther oxidation of the nitride layer. These properties were also related to the microstructure ol the Ti-Si-N film, which was characterized by nanosize d precipitates of silicon nitride phase in the TiN matrix and more randomly oriented grains.