The composition, microstructure and mechanical properties of Ni/DLC nanocomposite films by filtered cathodic vacuum arc deposition

摘要

In this paper, Ni/DLC nanocomposite films were deposited on the un-heated silicon (100) by the filtered cathodic vacuum arc deposition (FCVAD) under different CH4 and C2H2 flow rates. The composition, microstructure and mechanical properties of the Ni/DLC films were investigated by scanning electron microscopy (SEM), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD) and nanoindentation. The Ni/DLC films typically consisted of nickel nanograins around 11 nm, which were embedded in amorphous carbon matrix with the thickness of 035-2.8 nm. The film structure and the mechanical properties are strongly affected by the precursor gas type and flow rate. The porous structure, with the nanopore size equaling to the nickel grain size, can be seen after the etching process of the as-deposited film, providing a possible method for the preparation of nanoporous DLC films. A maximum hardness of 13.2 GPa and 21.64 GPa is achieved for the Ni/DLC films under the CH4 flow rate of 30 sccm and C2H2 flow rate of 40 sccm, respectively, under which the maximum thickness of the amorphous carbon phase is also obtained. (C) 2017 Elsevier B.V. All rights reserved.