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.