The prospect of spray pyrolyzed pure, Mn-doped, and Zn-doped nickel oxide thin films as TCO material

Abstract

Nickel Oxide films with Manganese (Mn) and Zinc (Zn) doping (NiO, Ni_1-xMn_xO, and Ni_1-xZn_xO; where x = 0, 0.02, 0.04, and 0.06) were fabricated using the spray pyrolysis technique on the glass substrates at 400 °C (673K) temperature. The XRD spectra revealed a polycrystalline nature of the films with cubic crystal structure and a favored growth orientation towards the (111) plane. The SEM micrographs revealed a smooth, homogeneous, and uniform surface, while the EDS spectra confirmed the presence of Ni, O, Zn, and Mn elements in the films. Optical analysis using UV-visible absorption spectroscopy demonstrated high transparency of the films in the visible region (400 nm-900 nm), and the transparency increased with higher Zn doping, reaching ∼85 % in Ni_0.94Zn_0.06O films. Conversely, Ni_1-xMn_xO films show a slight transmission decline with increasing Mn doping concentrations. The sheet resistance of the films was found to be decreased for low-concentration doping and again began to increase for highly doped Ni_0.94Zn_0.06O and Ni_0.94Mn_0.06O films. Among all the films, Ni_0.98Zn_0.02O exhibited the maximum figure of merit, showing the prospect for optoelectronic applications.