Structure and soft magnetic properties of sputter deposited MnZn ferrite films

In this paper we report the soft magnetic properties of thin films of sputtered MnZn ferrite deposited on thermally oxidized Si substrates. A high deposition temperature, 600 °C, together with the addition of water vapor to the sputtering gas was found to improve the initial ac permeability, μ. The highest value obtained was approximately 30. For MnZn-ferrite films with much larger grain sizes, as obtained by deposition on a polycrystalline Zn-ferrite substrate, a μ of 100 was obtained. The results are discussed in terms of the so-called nonmagnetic grain boundary model.