Investigation of structural, morphological, optical and electrical properties of Co/Ni co-doped ZnO thin films

This work reports on the preparation and characterization of zinc oxide (ZnO) thin films using spray pyrolysis technique on glass substrates. The effect of cobalt and nickel doping and nickel/cobalt co-doping on the structural, optical, morphological and electrical properties of obtained films have been investigated. The obtained films are characterized by different techniques such as X-rays diffraction (XRD), UV-Visible, Scanning electron microscopy (SEM) and four probes electrical measurements. The results of the XRD characterization indicate that all the films of interest have the wurtzite hexagonal polycrystalline structure with (002) preferred orientation. Images of scanning electron microscopy (SEM) were used to observe the effect of doping and co-doping on films surface. Spectroscopy measurements in UV-VIS wavelength range have found to give good values of transmission (average value = 85%) for all elaborated layers, with a high transmission of 93% for the film deposited at 3%Ni. The films exhibit high transmittance around 85% with the presence of interference fringes in the visible region, indicating the films homogeneity and smoothness. The deduced optical gap values from optical measurement are found to be in the range of 3.26-3.30 eV. The electrical analysis shows that the conductivity increases with the co-doping compared to the pure ZnO film. The characterization of ZnO film co-doped 3%Ni:3%Co showed that the material under focus is a good candidate for optoelectronic applications such as the manufacture of solar cells with transparent electrodes. (C) 2020 Elsevier B.V. All rights reserved.

Automated summary

This study reports the preparation and characterization of zinc oxide thin films on glass substrates using spray pyrolysis technique. The effects of cobalt and nickel doping, as well as nickel/cobalt co-doping, on the properties of the films were investigated. The co-doped ZnO film with 3%Ni:3%Co showed potential for optoelectronic applications such as solar cell manufacturing with transparent electrodes.