In this work, the electric properties of carbon films embedded by nickel nanoparticles deposited at different deposition times 50-600 sec were investigated. It can be seen that the deposition time affects on nanoparticle sizes and thicknesses of films. A detailed analysis in terms of phonon-assisted small polaron hopping model is used to correlate electrical transport properties of films in temperature range 150-300 K.With increasing deposition time from 50 to 180 sec the polaron radius (rp) decrease and then from 180 to 600 sec it increased. The polaron radius (rp) of films deposited at 180 sec has minimum value of 8.14 × 10−8cm. The polaron hopping energy (WH) of films deposited at 180 sec has minimum value 0.028 eV. With increasing deposition time from 50 to 180 sec the density of states N (EF) at the Fermi level increase and then from 180 to 600 sec it decreased. The density of states N (EF) at the Fermi level of films deposited at 180 sec has maximum value of 6.09 × 1020 eV−1cm−3.
