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SiNxand diamond-like carbon (DLC) films were prepared simultaneously on Si substrates by the RF magnetron sputtering of a silicon nitride (Si3N4) target and the filtered cathodic arc (FCA) deposition of graphite, respectively. The RF power was fixed at 100 W, while the arc current of graphite for the FCA deposition was varied from 20 to 80 A. The structure of composite SiNx/DLC films was investigated by Raman spectroscopy. The chemical composition and chemical state of the films were analyzed by X-ray photoelectron spectroscopy (XPS). Results revealed that the atomic concentration of carbon (C) increased, while those of silicon (Si) and nitrogen (N) decreased with increasing arc current. In addition, the sp3content in the composite films was found to increase with the arc current. This result indicates that the structure and property of the composite films can be controlled according to their required applications by varying the arc current.

Composite SiNx/DLC films were deposited on silicon substrate by co-deposition system. The carbon plasma was generated by filtered cathodic arc source, simultaneously incorporated with silicon nitride from RF magnetron sputtering. The silicon nitride sputtering rate was maintained by fixed RF power at 100W while the arc current of FCA was varied from 20 to 80A.The SiNx/DLC film composition and optical properties were investigated by X-ray photoelectron spectroscopy and spectroscopic ellipsometry respectively. The results revealed that the atomic concentration of carbon increased while those of silicon and nitrogen decreased with increasing arc current. The oxidation was found on the film surface and related to the atomic concentration of silicon. The optical properties can be changed as a function of carbon concentration by setting different arc current. In this work, the volume percentage of carbon obtained from spectroscopic ellipsometry using Bruggeman EMA model showed good numerical correlation with the atomic percentage of carbon from XPS analysis with the range spanning across 75-95 at. %.

Significant improvements in dielectric properties of poly(vinylidene difluoride) (PVDF) can be achieved by adding small amounts of barium-modified porous clay heterostructure (Ba-PCH). In this article, composite films of PVDF with various amounts of Ba-PCH were fabricated by the compression method. SEM images indicated good dispersion of Ba-PCH in the PVDF matrix, as island-like particles caused improvement in the mechanical and thermal properties in the composite films. The films were highly heat resistant between 446°C and 452°C, depending on the amount of Ba-PCH added. The addition of Ba-PCH in the PVDF matrix reduced the non-polar phase, α-phase, of the PVDF, which resulted in the presence of a polar-phase, β-phase. There was a decrement of the non-polar phase of PVDF after adding small amounts of Ba-PCH, the dielectric constant (at 1 kHz) was dramatically increased from 6.0 of the neat compressed PVDF film to 34.1, 44.8, 47.1, and 56.0 of the compressed PVDF film with 3 wt. %, 5 wt. %, 7 wt. %, and 10 wt. % of Ba-PCH in the PVDF matrix, respectively.