High-frequency magnetic properties of Zn ferrite films deposited by magnetron sputtering

Abstract

The effect of thermal annealing on structural and magnetic properties has been investigated for Zn ferrite films deposited on Si (111) substrates using radio frequency magnetron sputtering. The saturation magnetization at room temperature was enhanced upto 303 emu/cm3 by annealing at relatively low temperature of 200 °C and decreased at higher temperatures. The complex permeability μ=μ′-iμ″ values of the ferrite films as-deposited and annealed at 200 and 400 °C were measured at frequency upto 5 GHz. These films exhibited better high-frequency properties, especially, the film annealed at 200 °C had a large μ′ of 19.5 and high resonance frequency fr of 1.61 GHz. And the reason was investigated preliminarily based on the bianisotropy model.