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Growth of SiC nanowires in plasma-assisted hot filament chemical-vapor-deposition by using hexamethyldisiloxane (HMDSO) as the gas source is reported. The SiC nanowires (SiC-NWs) grew on Au-coated silicon substrate with core-shell structure, where the core consisted of polycrystalline SiC grains and the shell exhibited amorphous structure. The featured structures such as cones, polyhedrons, ball-liked particles were observed in the case without plasma assistance. The underlying mechanism for the growth of nanostructures was also discussed. The high chemical activity induced by the plasma process plays an important role in using monomer to generate nanostructure.

Usually, the electrical breakdown of dielectric barrier discharge (DBD) at atmospheric pressure leads to a filamentary non-homogeneous discharge. However, it is also possible to obtain a diffuse DBD in homogeneous form, called atmospheric pressure glow discharge (APGD). We obtained a uniform APGD in helium and in the mixture of argon with alcohol, and studied the electrical characteristics of helium APGD. It is found that the relationship between discharge current and source frequency is different depending on the difference in gas gap when the applied voltage is kept constant. The discharge current shows an increasing trend with the increased frequency when gas gap is 0.8 cm, but the discharge current tends to decrease with the increased frequency when the gas gap increases. The discharge current always increases with the increased applied voltage when the source frequency is kept constant. We also observed a glow-like discharge in nitrogen at atmospheric pressure.

Atmospheric pressure surface discharge is shown to have great prospects for a number of industrial applications. To acquire better results in application fields and considering that the study of the basic parameters including electron temperature and electron density is desirable, we develop an equivalent circuit model and the diagnostic techniques based on optical emission spectroscopy and electrical measurement in our laboratory. The electron temperature has been determined to be about 0.7 eV by a Fermi–Dirac model. The electron density has been calculated to be near 1010cm−3 from a time resolved electrical measurement (Ohmic heating method).

The hot filament assisted double-bias hydrogen has been employed for the surface fabrication of the as-formed chemical vapor deposited diamond films on the nanometer scale. Diamond cone arrays are successfully prepared through hydrogen plasma etching. The intrinsic columnar structure of the diamond films leads to the unevenly distributed ion etching rate, which plays an important role in the cone formation. Simultaneously, the carbon-containing species sputtered out may re-deposit on the surface. The evolvement of the characteristic surface is thus determined by the competition between the ion etching and the carbon deposition. The application of grid electrode influences the discharge characteristics at the substrate region. By controlling the grid current, the surface structure of diamond films may be significantly tuned. Moreover, by introducing small amounts of methane in the etching process, the increased concentration of carbon-containing species enhances the secondary diamond nucleation on the film surface, which further promotes the uniformity of the diamond cone arrays.