Enhancing High-Frequency Properties of Nanocrystalline Sputtered Fe Thin Films by Using MnIr Underlayer and Oblique Deposition

In this work, the single-layer Fe and the bilayer MnIr/Fe thin films were fabricated on Si (100) substrate using the oblique-angle sputtering technique. The structure and magnetic properties of the as-deposited films were investigated. MnIr biased layer deposited at the normal incidence angle develops an exchange bias field of 5.2 Oe which leads to an increase in the uniaxial anisotropy field of Fe layer from 4.36 to 23.66 Oe and the ferromagnetic resonance frequency from 1.02 to 1.46 GHz. It is also found that the resonance frequency of the bilayer MnIr/Fe rises sharply from 1.46 to 5.05 GHz as the incident angle increases from 0 to 36°.