The relation between the average diameter of CNTs on Ni-Cu @ a-C:H catalyst with the optical absorption edge and the optical dispersion parameters

Effect of deposition rate on micromorphology analyses and optical parameters in amorphous carbon nickel thin films

In this work, the micromorphology of the Ni @ amorphous carbon films and their relationship to other optical properties using atomic force microscopic (AFM) imaging were examined. The surface topography of these Ni @ amorphous carbon sheets was reported using stereometric analysis and the SPIPTM 6.7.4 software in compliance with ISO 25178-2:2012 and ASME B46.1-2009. It is clear that the Ni @ amorphous carbon films deposited at 180 s had more the root mean square height (Sq) at around of 0.1475 mm and has the greatest value in comparison to other films. The Ni @ amorphous carbon films deposited at 600 s had a more regular surface because their the root mean square height (Sq) had minimum value of 0.1360 mm. The peak energy positions of optical density for the films deposited at 180 s which were the lowest value and about of 1.65 eV, could be due the quasi-metallic mode. The cut-off energy for the skin/shell depth parameters of the Ni @ amorphous carbon films were about 3.5 eV/ or 353 nm. The Ni @ amorphous carbon films deposited at 180 s had the lowest value of the electron - phonon interaction energy, (Ee-p). The small polaron model shown that as input photon energy was increased, the calculated AC conductivity by optical data for the Ni @ amorphous carbon films was decreased.