Study of pure Ni, NiO, and mixture of Ni-NiO thin films on piezoelectric lithium niobate substrate by pulsed laser deposition

Abstract

The crystallographic orientation plays a significant role in the modern magnetic heterostructure devices, especially in the arena of spintronics. In terms of magnetic property, domain orientation is solely dependent on structural homogeneity. This research work deals with the development of pure Ni, NiO, and mixture of Ni-NiO thin films on a single-crystalline piezoelectric lithium niobate substrate. Pulsed laser deposition technique was used at 650 °C in a reduction and oxidation atmosphere for pure Ni and NiO deposition respectively, whereas deposited NiO was reduction annealed to achieve mixture of Ni (ferromagnetic)-NiO (antiferromagnetic) thin film on a piezoelectric lithium niobate substrate. X-ray diffraction along with x-ray reflectometry was carried out for better understanding of surface nature and thickness of the film. Morphological analysis of the films was conducted using scanning electron microscopy with energy dispersive X-ray spectrum. Atomic force microscopy as well as ferromagnetic resonance were used to understand the magnetic characteristics of the thin films. Additionally, surface properties of the films with Ni and O oxidation states were investigated by X-ray photoelectron spectroscopy. Our findings indicate that Ni and mixture of Ni-NiO thin films exhibit similar dynamic magnetic characteristics, making Ni-NiO films a more attractive option for spintronic applications because of their adjustable magnetic properties.