High-Frequency Performance of Co<sub>2</sub>FeAl Half-Metallic Films Prepared by Oblique Sputtering under Various Deposition Conditions

Abstract

Co2FeAl full-Hesuler alloys show good soft magnetic properties, implying a promising high ferromagnetic resonance frequency. In this study, Co2FeAl films were deposited on Si (100) substrates using an oblique sputtering method. As expected, a good high-frequency performance was achieved in the as-deposited Co2FeAl films without any annealing. An obvious uniaxial magnetic anisotropy over 200 Oe with the magnetic hard axis along the radial direction of the sample turntable was obtained. As a result, the self-bias ferromagnetic resonance frequency reaches more than 4 GHz for the Co2FeAl films prepared under an integrated circuits compatible process. These results indicate that the Co2FeAl films are promising in integrated circuits RF/microwave devices.