Electrical and magnetic properties of ZnNiO thin films deposited by pulse laser deposition

ZnNiO thin films with different contents of Ni (0–10 at.%) were fabricated on quartz and Si (100) substrates by pulsed laser deposition (PLD). We measured the samples by X-ray diffraction (XRD), field-emission scanning electron microscope (FE-SEM), X-ray photoelectron spectroscopy (XPS), ultraviolet-visible spectrometer (UV-VIS), and Hall testing. When the Ni contents were below 3 at.%, partial Zn²⁺ ions were replaced by the Ni²⁺ ions without forming any other phases, which enhanced the conductivity of the film. When the Ni contents were above 3 at.%, Ni ions were at the interstitial sites, and Ni-related clusters and defects were able to emerge in the films, resulting in a worsening of electrical and optical properties. A ferromagnetic hysteresis with a coercive force of approximately 30 Oe was observed in the ZnNiO film with a Ni content of 3 at.% at room temperature.