•A highly porous carbon film was coated on nickel foam employing MPCVD.•A 3D-crosslinked nanoscale network owned high degree of graphitization.•High stability of 95% of capacitance retention after 10,000 cycles.•Ideal electric double-layer capacitive and quick charge/discharge behavior.•Facile synthetic route for large-scale production.Highly porous carbon film (PCF) coated on nickel foam was prepared successfully by microwave plasma-assisted chemical vapor deposition (MPCVD) with C2H2 as carbon source and Ar as discharge gas. The PCF is uniform and dense with 3D-crosslinked nanoscale network structure possessing high degree of graphitization. When used as the electrode material in an electrochemical supercapacitor, the PCF samples verify their advantageous electrical conductivity, ion contact and electrochemical stability. The test results show that the sample prepared under 1000 W microwave power has good electrochemical performance. It displays the specific capacitance of 62.75 F/g at the current density of 2.0 A/g and retains 95% of its capacitance after 10,000 cycles at the current density of 2.0 A/g. Besides, its near-rectangular shape of the cyclic voltammograms (CV) curves exhibits typical character of an electric double-layer capacitor, which owns an enhanced ionic diffusion that can fit the requirements for energy storage applications.

Amorphous Al–Mg–B thin films were synthesized via a combinatorial sputtering approach. The properties of Al–Mg–B films with the varying deposition temperature was investigated. The deposition temperature was found to dominate the hardness of the amorphous as-deposited film. The hardness increases with increasing deposition temperature and may even exceed that of crystalline AlMgB14 material. The high hardness may be attributed to the existence of randomly distributed B12 icosahedra structure. Therefore, the thin film that was deposited on cemented carbide shows well-cutting performances in turning Ti alloy bar. At the same time, an appropriate method of pretreatment is the key to ensure the coating tool with the excellent adhesion by impact fracture test.

Boron-doped hydrogenated nanocrystalline silicon (nc-Si(B):H) films were prepared by electron cyclotron resonance plasma-enhanced chemical vapor deposition (ECR-PECVD). The effect of Ar/H2 ratio on the characteristic of as-grown nc-Si(B):H films was investigated systematically with Raman scattering, XRD, XPS as well as Hall effect measurements. The experimental results indicate that the increase of Ar/H2 ratio can enhance the concentration of B in the as-grown films. On the other hand, with the Ar/H2 ratio increasing, the crystallinity of the films deteriorated sharply, and the electrical properties of the as-grown films decreased. Langmuir Probe was used to investigate the electron temperature (Te) of microwave activated B2H6/Ar/H2 plasmas. Finally, the microscopic mechanism of the enhancement in doping efficiency was elucidated in terms of the plasma reaction equations of B2H6 and Langmuir probe testing result.Highlights► We investigated the influence of Ar/H2 ratio on the characteristics of B-doped films. ► Diluting process gas H2 with Ar did enhance the doping amount of B2H6 in the films. ► The crystallinity of the films decreased intensively with Ar/H2 ratio increasing. ► The microscopic mechanism of the enhancement in doping efficiency was elucidated.

Phosphorus-doped hydrogenated nanocrystalline silicon films (nc-Si(P):H) were prepared by electron cyclotron resonance plasma-enhanced chemical vapor deposition. The effect of Ar/H2 ratio on the characteristics of as-grown nc-Si(P):H films was investigated systematically with Raman scattering, Hall effect measurements as well as Fourier Transform infrared spectroscopy (FTIR). The results indicated that the Ar/H2 ratio played a critical role for the crystalline quality and electrical properties of the nc-Si:H films. FTIR also showed that infrared spectrum intensity of SiH2 bonding mode peak decreased when Ar/H2 ratio increased. The optimal value Ar/H2 ratio of 10/15 was obtained for high quality nc-Si(P):H films with high electron density and the mechanism was elucidated in terms of Raman and FTIR analysis.

Ternary AlMgB thin films were synthesized on silicon (100) substrate at 573 K by radio frequency (RF) magnetron sputtering method using one Al/Mg co-target and one boron target. The thickness of the as-deposited thin film was controlled to 500 nm by adjusting deposition time. The influences of sputtering powers on the elemental contents and structural and mechanical properties were investigated by electron probe microanalysis (EPMA), X-ray diffraction (XRD), high-resolution transmission electron microscopy (HR-TEM), and nanoindentation system. At the same time, the ball-on-disk tribometer was used to measure the friction behavior of the films. Experimental results indicate that the as-deposited boron-rich films are primarily amorphous structure and possess a dramatic high hardness up to 39 GPa with 99.03 at.% boron. Obviously, it has exceeded the hardness value of 32 GPa of pure AlMgB14 bulk material prepared by sintering method. Furthermore, the friction coefficients of the thin films exhibit an average value as low as 0.3, which is considered as the effect of self-lubricating.

Pseudobinary Ti1−xAlxN films were synthesized on Si (100) wafer by DC magnetron sputtering method using Ti1−xAlx alloy targets with different Al contents. The composition of the Ti1−xAlxN films was determined by electron probe microanalysis (EPMA). Structural characteristic was performed by X-ray diffraction (XRD), transmission electron microscopy (TEM), and high-resolution TEM (HRTEM). First principles virtual crystal calculations for the Ti1−xAlxN disordered alloys were used for the XRD simulations. The crystalline structure of the Ti0.61Al0.39N film was found to be a metastable single phase with NaCl (B1) structure. Its lattice constant, determined by XRD, was less than that of pure TiN. With the increase of Al content, the lattice constant of B1 phase was continually decreased, while würtzite (B4) structure was observed in the Ti0.40Al0.60N film. When x reached 0.75, the B1 phase disappeared, and only B4 phase was remained. The critical Al content for the phase transition from NaCl to würtzite structure in this paper was about 0.60, which could be explained by both the thermodynamic model and the electron theory. As-deposited Ti1−xAlxN films exhibited excellent mechanical properties. Hardness measurements of Ti1−xAlxN films showed a high value of 45GPa for x=0.39 and was decreased to value of 27 GPa with increasing Al at x=0.60.

Al-doped ZnO thin films were deposited by radio frequency magnetron sputtering using a ZnO target with 2 wt.% Al2O3. The structures and properties of the films were characterized by the thin film X-ray diffraction, high resolution transmission electron microscopy, Hall system and ultraviolet/visible/near-infrared spectrophotometer. The Al-doped ZnO film with high crystalline quality and good properties was obtained at the sputtering power of 100 W, working pressure of 0.3 Pa and substrate temperature of 250 °C. The results of further structure analysis show that the interplanar spacings d are enlarged in other directions besides the direction perpendicular to the substrate. Apart from the film stress, the doping concentration and the doping site of Al play an important role in the variation of lattice parameters. When the doping concentration of Al is more than 1.5 wt.%, part of Al atoms are incorporated in the interstitial site, which leads to the increase of lattice parameters. This viewpoint is also proved by the first principle calculations.

A new two-step growth method was proposed to fabricate microcrystalline silicon (μc-Si:H) thin films by an electron cyclotron resonance plasma enhanced chemical vapor deposition (ECR-PECVD). An ultra thin Si film was first deposited and followed by H2 plasma treatment for few minutes, and then the μc-Si:H film was deposited on it. High-resolution transmission electron microscope (HRTEM) and Raman spectrometer were used to study the microstructures and the crystalline volume fraction of μc-Si:H films. The HRTEM results show that the amorphous silicon thin film with a thickness of 15 nm can be crystallized by H2 plasma treatment in 2 min, and then it serves as the seed layer for the subsequent growth of μc-Si:H films. By optimizing the deposition parameters, the μc-Si:H film without amorphous incubation layer can be fabricated by this new two-step method and a proper crystalline volume fraction of 50.6% can be obtained.