Evolution of mechanical property of nanocomposite TiSiN films using reactive magnetron cosputtering

Abstract

The nanocomposite Ti-Si-N thin flims were prepared by reactive magnetron co-sputtering system. The experimental parameter effect on the evolution of mechanical property of nanocomposite TiSiN Films was investigated. The Ti-Si-N film is a mixed composite consisting of the Ti-Si, Ti-N and Si-N compounds. As Si is added to the polycrystalline Ti-N compound to form Ti-Si-N, the microstructure becomes nanocrystalline grains embedded in a disordered Ti-Si-N or SiN <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">x</sub> amorphous matrix i.e. nanocomposite quasi-amorphous microstructure, which is affected by the experimental parameters of nitrogen flow ratio (FN <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> %, 3, 5, 10 %), Ti power (75, 100, 150 W) and Si power (100, 150 and 200 W) during co-sputtering. The thickness, structural, morphology, chemical composition and mechanical properties of films were characterized by alpha-stepper profiler, Grazing Incidence X-ray Diffraction (GIXRD), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and nanoindenter, respectively. The experimental result shows that deposition rate decreased with increasing FN <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> %. According to Scherrer's formula, the grain size of films was below 5 nm. The surface morphology each film was very smooth due to fine grains. The hardness and modulus of Ti-Si-N can be enhanced by Ti power and reducing Si power. In this paper, the maximum hardness of 24.86 GPa and Young's modulus of 183.65 GPa was obtained at Ti 150 W, Si 100 W and 5 FN%.