Microwave magnetic properties of spinel ferrite films deposited by one-step electrochemical method

Spinel ferrites have been widely used in microwave devices due to their excellent electromagnetic properties. In this study, two kinds of spinel ferrite films, Fe3O4 and CoxFe3-xO4,were grown on Pt(111)/Ti/SiO2/Si substrates by one-step electrochemical deposition method. The XRD and SEM characterizations demonstrated that the orientation of the ferrite films changed from (111) to (100) with the increase of depositing time. The cobalt content within CoxFe3-xO4 films was studied in detail by EDS analysis. The ferromagnetic resonance (FMR) responses of the ferrite films were measured by the flip-chip method using a vector network analyzer (VNA). It showed that the FMR frequency of Fe3O4 films reached to 10:5 GHz under an out-plane magnetic field of 5 kOe, while it reached to 27 GHz under an in-plane magnetic field of 5 kOe for CoxFe3-xO4 films. Meanwhile, whether the magnetic field was applied parallelly or perpendicularly, the resonant peaks were increased linearly with increasing the magnetic field, indicating that the films are promising candidates for applications in tunable wave-absorbing materials or other tunable frequency devices. (C) 2017 Elsevier B.V. All rights reserved.