Soft Magnetic Properties and Microstructures of As-sputtered Fe-M-O (M=Hf, Al) Films

Fe-M-O (M=Hf, AD films are fabricated by Ar+O2 reactive sputtering and their magnetic properties are investigated. Excellent soft magnetic properties at high frequency are obtained in Fe-Hf-O and Fe-Al-O thin films even in an as-deposited state; for example, Fe82Hf3.4O14.6 and Fe90.7Al2O7.3 films exhibit the values of 17.7 and 18.5 kG for saturation magnetization, 1.0 and 0.65 Oe for coercivity, and 2,200 and 3,000 for the effective permeability at 100 MHz, respectively. Microstructures, magnetic anisotropy and electrical resistivity are investigated to understand the magnetic properties of the thin films.