Reasearch On Nanocomposition Ti-Si-N Thin Films Deposited By Cathodic Vacuum Arc

Ti-Si-N thin films with different silicon content were deposited by a cathodic arc technique in an Ar+N₂+SiH₄ mixture atmosphere. We mainly focus on the effect of silane flow rate on the Ti-Si-N films. The results show that the Ti-Si-N film consists of TiN crystallites and the amorphous phase of SiN_x. With the increase of silane flow rate, the content of silicon in the Ti-Si-N films varies from 2.0 at.% to 12.2 at.%. With 8.3at.% silicon content, the film shows two peaks: (111) and (200). The reference TiN films show a preferred orientation of (111) crystal plane. As Si is incorporated into the films, the intensity of (111) peak decreases. The peak becomes broader with the increase of Si content. The wider peak suggests the decrease of TiN crystallite size in the films. Meanwhile, the cross-sectional morphology of these films changes from a pronounced columnar microstructure to a dense, fine-grained structure. When the silicon content reaches about 8.3at.%, the films represent good qualities. The hardness of Ti-Si-N film reaches as high as 35GPa and the friction coefficient decrease a half percent, and the corrosion current would decrease by two to three orders magnitude than that of the TiN coated samples.