Electric Susceptibility and Energy Loss Functions of Carbon-Nickel Composite Films at Different Deposition Times

In this work, the optical properties of carbon–nickel films deposited at different deposition times from 50 to 600 sec were investigated. The obtained data of the refractive index n can be analyzed to obtain the high–frequency dielectric constant which describes free carriers and the lattice vibration modes of dispersion. The lattice dielectric constant εL and the plasma frequency ωp at 180 sec have maximum values 10.68 and 79.92x106 Hz, respectively. The free carrier electric susceptibility measurements in the wavelength range (300 – 1000 nm) are discussed according to the Spitzer–Fan model. It is shown that the electric susceptibility at 180 sec has a maximum value and with increasing wavelength it increases. The energy loss by the free charge carriers when traversing the bulk of the films at 180 sec has a maximum value and with increasing wavelength it decreases. The field emission scanning electronic microscopy (FESEM) images were used for estimation of particle size.