MWCNTs synthesized on Ni Cu NPs @ a-C:H films: study of the dielectric relaxation time, the free carriers concentration and the dissipation factor with different Ni layers thickness

摘要

In this paper, we reported the optical constants and dissipation electrical energy of MWCNTs synthesized on Cu-Ni nanoparticles in hydrogenated amorphous carbon with different Ni layer thicknesses using capacitance coupled radio frequency plasma enhanced chemical vapor deposition (RF-PECVD) system. It can be seen that the Multi-Walled Carbon Nanotubes, MWCNTs, synthesized have maximum value of the average diameters in films deposited with 15 nm Ni layer thickness. With increase of Ni layer thickness, the dielectric relaxation time peaks nearly obtain a blue shift. The RBS spectra results shown that Ni nanoparticles successfully was presented in thin films. Due to the maximum value of the trapping incident photons on films surface, films deposited with 5 nm Ni layer thickness have maximum value of the absorption edge. The values of the free carriers electric susceptibility, chi(c), in thin films with 15 nm Ni layers thickness, for all range wavelengths, have maximum values and they were increased with increasing wavelength. Films deposited with 10 nm Ni layer thickness have the maximum value of dissipation factor.