Structure and Isotropic High-Frequency Response of Co-HfN Nanogranular Films

Author

Yang Cao ; Yiwen Zhang ; Ohnuma, Shigehiro ; Kobayashi, Nobukiyo ; Masumoto, Hiroshi

Author_Institution

Frontier Res. Inst. for Interdiscipl. Sci., Tohoku Univ., Sendai, Japan

Volume

51

Issue

11

fYear

2015

Firstpage

1

Lastpage

4

Abstract

The Co-HfN nanogranular films with different Co content were deposited, to obtain high-frequency soft magnetic properties. The films exhibit perpendicular magnetic anisotropy over a wide composition range. The coercivity is ~15-75 Oe, which is attributed to the growth-induced Co columnar structure. Both hysteresis loops and magnetic force microscopy images demonstrate that the films are magnetically in-plane isotropic. The permeability and ferromagnetic resonance frequency of the Co₅₈Hf₁₄N₂₈ films are 40 and 2 GHz, respectively, which is consistent with the theoretical calculation based on Landau-Lifshitz-Gilbert (L.L.G) equation. The films consist of crystallized Co nanogranules and amorphous HfN matrix.

Keywords

amorphous state; cobalt; coercive force; ferromagnetic resonance; hafnium compounds; magnetic force microscopy; magnetic hysteresis; magnetic permeability; magnetic thin films; nanofabrication; nanomagnetics; nanostructured materials; nitrogen; perpendicular magnetic anisotropy; soft magnetic materials; Co-HfN nanogranular films; Co₅₈Hf₁₄N₂₈; Landau-Lifshitz-Gilbert equation; amorphous HfN matrix; coercivity; crystallized Co nanogranules; ferromagnetic resonance frequency; growth-induced Co columnar structure; high-frequency soft magnetic properties; hysteresis loops; isotropic high-frequency response; magnetic force microscopy; magnetic permeability; perpendicular magnetic anisotropy; structure response; Films; Magnetic hysteresis; Magnetic noise; Magnetic properties; Perpendicular magnetic anisotropy; Soft magnetic materials; Cobalt alloys; frequency response; perpendicular magnetic ansotropy; soft magnetic materials;

fLanguage

English

Journal_Title

Magnetics, IEEE Transactions on

Publisher

ieee

ISSN

0018-9464

Type

jour

DOI

10.1109/TMAG.2015.2438003

Filename

7113862