Improvement of Soft Magnetic Properties of Si/NiFe/FeCoB Thin Films at Gigahertz Band Frequency Range by Multilayer Configuration

Author

Hashimoto, A. ; Nakagawa, S. ; Yamaguchi, M.

Author_Institution

Dept. of Phys. Electron., Tokyo Inst. of Technol.

Volume

43

Issue

6

fYear

2007

fDate

6/1/2007 12:00:00 AM

Firstpage

2627

Lastpage

2629

Abstract

Frequency dependence of relative permeability up to 9 GHz in Si/NiFe/FeCoB thin films was measured. In 200-nm-thick FeCoB thin film, mu´ reached about 70 and remained up to 3 GHz then decreased precipitously. Furthermore, mu´´ indicated its resonance frequency f _r at 6.4 GHz and produced prominent peak around the frequency. It was found that permeability characteristics increased loss term and lost its prompt responsivity when increasing thickness of FeCoB layer. Then a film with multilayer configuration was suggested in order to suppress the loss. The problems in multilayer configuration were solved and a multilayer film with fine soft magnetic properties was developed by insertion of Si/NiFe layers as intermediate layer. The multi-FeCoB-layer film with Si/NiFe intermediate layer indicated loss-suppressed permeability and good performance in permeablity at high frequency range

Keywords

boron alloys; cobalt alloys; iron alloys; magnetic multilayers; magnetic permeability; magnetic thin films; nickel alloys; silicon; soft magnetic materials; 200 nm; 3 GHz; 6.4 GHz; 9 GHz; Si-NiFe-FeCoB; intermediate layer; multilayer configuration; permeability; resonance frequency; soft magnetic properties; thin films; Frequency dependence; Frequency measurement; Magnetic films; Magnetic multilayers; Magnetic properties; Permeability measurement; Resonance; Semiconductor films; Semiconductor thin films; Transistors; High-frequency; permeability; resonance frequency; soft magnetic material; thin film;

fLanguage

English

Journal_Title

Magnetics, IEEE Transactions on

Publisher

ieee

ISSN

0018-9464

Type

jour

DOI

10.1109/TMAG.2007.893797

Filename

4202752