•Ni/DLC films were deposited under different CH4 and C2H2 flow rate by FCVAD.•The evolution of grain structure, phase type and film structure occurred with the different gas type and flow rate.•The porous carbon structure can be obtained by the etching process of the Ni/DLC films.•The effective load transfer and the second-phase strength might be responsible for the hardness strength mechanism.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 0.35–2.8 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.Download high-res image (115KB)Download full-size image

The titanium carbide/amorphous carbon nanocomposite films have been deposited on silicon substrate by filtered cathodic vacuum arc (FCVA) technology, the effects of substrate bias on composition, structures and mechanical properties of the films are studied by scanning electron spectroscopy, X-ray diffraction and X-ray photoelectron spectroscopy and nano-indentation. The results show that the Ti content, deposition rate and hardness at first increase and then decrease with increasing the substrate bias. Maximum hardness of the titanium carbide/amorphous carbon nanocomposite film is 51 Gpa prepared at −400 V. The hardness enhancement may be attributed to the compressive stress and the fraction of crystalline TiC phase due to ion bombardment.

Nc–Cu/a–C:H nanocomposite films are deposited by filtered cathodic vaccum arc (FCVA) technique using C2H2 as the precursor. The effects of C2H2 flow rate on the microstructure, composition and properties of nc–Cu/a–C:H films have been studied by Raman spectroscopy, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and nanoindentation test. In these films, copper nanoparticles (3.5–15 nm) are embedded in the amorphous carbon matrix, which could be confirmed by XRD analysis. Raman spectroscopy and XPS results confirm the decrease of sp3 content with the increasing copper fraction, which could be a result of more severe thermalization on carbon matrix owing to the presence of copper. The compressive stresses of these films, calculated by Stoney’s equation, are found to be as low as 0.5 Gpa, declining with the increasing copper content. Nanoindentation measurements reveal that the film hardness falls monotonically as the Cu content in the films increases.

Thin films of zirconium oxynitride (ZrOxNy) were deposited onto glass and Si substrate at room temperature by filtered cathodic vacuum arc (FCVA) technology using air as a reactive gas. The compositions and structures of the zirconium oxynitride films influenced by air flow rate were investigated by scan electronic spectroscopes, X-ray diffraction and X-ray photoelectron spectroscopes. The results showed that crystal structure of the films transformed from ZrO and ZrN mixed phases to ZrN phase with the increasing air flow rate. The hardness, elastic modulus and elastic recovery parameter (ERP) of the zirconium oxynitride films were also determined by nano indentation tests. At the optimum deposition parameters, the hardness and elastic modulus values reached 28.94 GPa and 253.44 GPa respectively; good wear resistant properties were also achieved due to the high H/E ratio (0.115) and good elastic recovery (86.18%). The optical band gap of the film at the optimum deposition parameter was 1.91 eV, implying that the film had great potentials in many photocatalytic and optoelectronic applications.Highlights► Synthesis of ZrOxNy thin film by filtered cathodic vacuum arc technology. ► Using the air as a reactive gas can reduce the processing time. ► The mechanical property and optical band gap of the films were investigated.