Preparation and Characteristics of γ-Fe2O3 Magnetic Disks by Magnetron Sputtering Method

Thin films of γ-Fe2O3 have been studied for application in high-density magnetic recording media because of their superior magnetic properties, wear resistance and chemical stability. Several processes were proposed for the fabrication of the γ-Fe2O3. We have been investigating the γ-Fe2O3 films preparation process consisting of Fe3O4 film deposition and heat treatment. Fe3O4 film were deposited by the reactive RF magnetron sputtering of an iron tatget in Ar+ O2 atmosphere and then transformed into γ-Fe2O3 films by the oxidation heat treatment. We report on the high rate of deposition of Fe3O4 films by magnetron sputtering. The deposition rate of Fe3O4 film by magnetron sputtering was about five times higher than that by diode sputtering. Fe3O4 films were transformed into γ-Fe2O3 films by heat treatment in air. The magnetic properties of γ-Fe2O3 films obtained in the above experiment were as good as those by the diode sputtering method.