Effect of Substrate Temperature on the Growth and Properties of Nanocrystalline NiO Thin Films

Abstract

In the present research, the NiO thin films have been deposited by pneumatic spray method at various substrate temperatures. The main object is to find a good structural, optical and electrical properties of NiO tin films with substrate temperature effected. A set of deposition temperature (380, 400, 420, 440 and 460 °C), the NiO thin film was deposited on glass substrate with 0.1 M. Nanocrystalline films with a polycrystalline cubic crystal with (111) and (200) peaks, it is a strong (111) preferred orientation. The minimum value of grain size G = 16.88 nm was obtained for deposited film at 420 °C. The optical spectra show that the NiO thin films become transparency in visible region, but the film deposited at 460 °C have a high transmission. The band gap energy was located between 3.43 and 3.63 eV, the minimum was obtained for sprayed film at 440 °C. The minima value of Urbach energy was 0.25 eV, it also was found at 440 °C. The electrical property of deposited NiO films at 440 °C has a minimum value of electrical resistivity. The best structure, optical and electrical characterizations of NiO thin films are achieved and begin from deposited temperature of 420 °C.

The Deposition Temperature Dependence on the Crystallite Size of NiO Thin Films

“…The NiO samples were fabricated on the glass substrates using a pneumatic spray technique with 0.1 M of the precursor molarity. The NiO thin films were deposited at several deposition temperatures in the range of 380-460°C [5] (see Table 1). Table 1 presents that the NiO thin films were nanocrystalline and had a cubic structure with (111) crystal plane at the higher intensity, which has preferential a-axis orientation along with (111) crystal plane.…”

“…The lattice parameter a of cubic structure for NiO thin films was determined in Eq. 1and XRD patterns using the following formula [5]:…”

“…In the present article, we have studied and investigated a relationship to calculate the crystallite size (G) from the measured structural parameters of the X-ray diffraction in the NiO thin films. We have used the experimental data of NiO thin films prepared at several deposition temperatures in the range of 380-460°C [5], which present the following parameters, such as the diffraction angle 2θ, the full width at half-maximum (FWHM), the crystallite size G, the lattice parameter a and a − a 0 of (111) diffraction peak for NiO thin films at several deposition temperatures.…”

“…The diffraction angle 2θ, the full width at half-maximum (FWHM), the crystallite size G, the lattice parameter a and a − a 0 of (111) diffraction peak for NiO thin films at several deposition temperatures[5].…”

Spin coating method deposited nickel oxide thin films with various film thicknesses

“…[9][10][11] NiO thin films can be obtained by several deposition methods, including electrochemical deposition, pulsed laser deposition, magnetron sputtering, molecular beam epitaxy, reactive evaporation, sol-gel processes, chemical vapor deposition, and spray pyrolysis. 12,13 Among the above-mentioned techniques, sol-gel spin coating is a simple and effective method for coating thin films. It requires less equipment, low cost, and is faster when compared to other coating techniques.…”