Characterization of nanocrystalline nickel oxide thin films prepared at different thermal oxidation temperatures

Abstract

Nickel oxide (NiO) thin films were obtained by thermal oxidation of nickel layers coated on quartz. The influence of thermal oxidation temperatures on chemical and physical properties of prepared films was studied. X-ray results exhibited that all the films possess single cubic crystal structure phase of NiO along the (200) plane, and show good crystalline quality. The crystallinity of NiO films is increased with increase in oxidation temperature. Also, the structural parameters of the films were determined. The mean crystallite size was varied between 17 and 45 nm, which confirms the formation of nanocrystals in this study. Also, FTIR and EDS studies confirm the formation of NiO. According to SEM and AFM images, the grain size was influenced by augmentation in thermal oxidation temperature. The optical studies showed that with increase in thermal oxidation temperature, the transmittance increased, while the optical band gap decreased.