Soft magnetic granular material Co-Fe-Hf-O for micromagnetic device applications

A granular magnetic material, Co-Fe-Hf-O, has been developed-using dc pulsed magnetron reactive sputtering. The deposition rate is as high as 1.3 nm/s. The electrical and magnetic properties of Co-Fe-Hf-O film can be tuned by changing O-2 during deposition. A highly resistive, magnetically soft film has been achieved in a small range of the O-2/(Ar+O-2) gas flow ratio. The origin of the dependence of magnetic and electrical properties of this material is studied and explained by monitoring the evolution of the film microstructure, using x-ray diffraction and transmission electron microscopy. (c) 2005 American Institute of Physics.