Tuning of Magnetic and Optical Properties of Co0.8Zn0.2Fe2O4 Spinel Ferrite Thin Films Based on Post Annealing Temperature

Abstract

This paper is dedicated to deposit zinc substituted cobalt ferrite (Co0.8Zn0.2Fe2O4) thin films on glass substrate using electron beam deposition technique. The effect of post annealing temperature on structural, magnetic, and optical properties of thin films has been investigated. Thin films have been characterized using x-ray diffraction (XRD), Raman spectroscopy, atomic force microscopy (AFM), vibrating sample magnetometer (VSM), UV-VIS spectroscopy, and spectroscopic ellipsometry (SE) analysis. The as-deposited thin films are amorphous in nature. After deposition, these thin films post annealed at different temperature ranges from 200 to 500 ∘C to enhance the crystallinity of films. The film post annealed at 200 ∘C is also amorphous in nature. As the post annealing temperature increases, the thin films become more crystalline. X-ray diffractometer and Raman analysis confirm the formation of cubical inverse spinel structure of thin films. The saturation magnetization of the thin films decreases with the annealing temperature due to the sites occupancy of cations between tetrahedral and octahedral. The reduction in coercivity is correlated with the anisotropy constant, but the anisotropy value is still high which is suitable to form stable magnetic storage memories. The band gap energy are decreased which is mainly attributed due to increase in grain size of the film. It is noted that the band gap energy of these thin films are higher than that of bulk material, so these may be suggested for use in wide band gap applications.