Permeability and Magnetic Properties of Ferromagnetic NiFe/FeCoBSi Bilayers for High-Frequency Applications

Author

Gerber, A. ; McCord, J. ; Schmutz, C. ; Quandt, E.

Author_Institution

Smart Mater. Group, Center of Adv. Eur. Studies & Res. (Caesar), Bonn

Volume

43

Issue

6

fYear

2007

fDate

6/1/2007 12:00:00 AM

Firstpage

2624

Lastpage

2626

Abstract

In order to adjust the ferromagnetic resonance (FMR) frequency of thin NiFe films, ferromagnetic polycrystalline/amorphous NiFe/FeCoBSi bilayers using radio frequency magnetron sputtering were produced. Herein, the higher anisotropy field H_k of a ferromagnetic FeCoBSi was used to shift the FMR-frequency of the bilayer. Static and dynamic magnetic properties of the films were investigated by quasi-static magnetometry and by high frequency permeability measurements, respectively. The dynamic anisotropy field H_kdyn calculated from the FMR frequency of a single 100-nm NiFe-layer is shifted from mu₀H_kdyn=0.5 mT to mu₀H_kdyn=2.8 mT in a FeCoBSi(80 nm)/NiFe(20 nm) bilayer; whereas, the FMR frequency is congruently enhanced from 0.9 to 2.0 GHz. The permeability decreased from mu=2000 to mu=500. A linear dependence for the adjustment of the relevant magnetic parameters with NiFe:FeCoBSi ratio is demonstrated, opening the possibility to individually tailor magnetic properties of magnetic films for high-frequency applications

Keywords

amorphous magnetic materials; boron alloys; cobalt alloys; ferromagnetic materials; ferromagnetic resonance; iron alloys; magnetic anisotropy; magnetic permeability; magnetic thin films; nickel alloys; silicon alloys; 0.5 mT; 0.9 GHz; 2.0 GHz; 2.8 mT; FMR; NiFe-FeCoBSi; dynamic anisotropy field; dynamic magnetic properties; ferromagnetic bilayers; ferromagnetic resonance frequency; permeability; quasistatic magnetometry; radio frequency magnetron sputtering; static magnetic properties; thin films; Amorphous magnetic materials; Anisotropic magnetoresistance; Frequency; Magnetic anisotropy; Magnetic films; Magnetic properties; Magnetic resonance; Magnetosphere; Permeability; Perpendicular magnetic anisotropy; FeCoBSi; NiFe; magnetization dynamics; multilayer; permeability;

fLanguage

English

Journal_Title

Magnetics, IEEE Transactions on

Publisher

ieee

ISSN

0018-9464

Type

jour

DOI

10.1109/TMAG.2007.893786

Filename

4202732