Effect of annealing temperature on nano structural, morphological and optical properties of nickel oxide films prepared by thermal oxidation of nickel films deposited by electron beam evaporation

In this work, firstly the nickel thin films were deposited on silicon and quartz substrates by electron beam evaporation technique at the same deposition conditions. Then the prepared films were annealed at different temperatures of 400-700 °C in electrical furnace. The effect of annealing temperature on structural, morphological and optical properties of samples were investigated by X-ray diffraction (XRD), atomic force microscopy (AFM), scanning electron microscopy (SEM) and UV-Vis spectrophotometry. XRD results revealed the formation of crystalline nickel phases in annealing temperature of 400 °C and by increasing of annealing temperature from 500 °C to 700 °C the crystalline nickel oxide phases can be observed. The AFM and SEM images showed that the annealing temperature effectively influenced the morphology and surface roughness of films and the grain sizes increased by annealing temperature enhancement. Also the optical band gap values of nickel oxide films deposited on quartz substrates were calculated from transmittance data.