Effect of O2 Partial Pressure on Magnetic Properties of Alloys CoFe-Rich Nanocrystalline Thin Films

Alloys of CoFe-rich magnetic films are well known as typical soft magnetic alloys. They are used for many kinds of electric and electronic parts such as magnetic recording heads, transformers and inductors. In order to get superior soft magnetic properties of the CoFe-based nanocrystalline thin films, the effect of O2 partial pressure on magnetic properties of Co-Fe-Hf-O nanocrystalline thin films have been investigated. It is found that the soft magnetic properties and electrical property of these films show a dependence on the partial pressure of reactive gases, which presumably changes the microstructure of the films and related magnetic anisotropy. With optimal conditions, thin film exhibit excellent soft magnetic properties: saturation magnetization (4πMs) of 21 kG, magnetic coercivity (Hc) of 0.18 Oe, anisotropy field (Hk) of 49 Oe, and an electrical property is also shown to be as high as 300 μcm. The combination of high 4πMs and relatively high Hk in these films are believed to be partly responsible for the excellent ultra-high-frequency behavior

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Fe-Cr-N Based Nanocrystalline Soft Magnetic Thin Films

MRS Proceedings ◽

10.1557/proc-475-445 ◽

1997 ◽

Vol 475 ◽

Author(s):

W. Zhu ◽

T. H. Tiefel ◽

S. Jin ◽

R. B. Van Dover ◽

V. Korenivski

Keyword(s):

Thin Films ◽

Magnetic Properties ◽

Easy Axis ◽

Anisotropy Field ◽

Magnetic Thin Films ◽

Film Plane ◽

Soft Magnetic Properties ◽

Soft Magnetic ◽

Frequency Behavior ◽

Post Deposition

ABSTRACTWe have investigated the soft magnetic properties of new Fe-Cr-Ta-N and Fe-Cr-Hf-N alloy films. Thin films with compositions in the range of Fe-2∼8%Cr-0∼l%Ta (or Hf)-5∼10%N (in atomic %) were prepared by reactive sputtering in a nitrogen-containing atmosphere. The films, most likely nanocrystalline, exhibit excellent soft magnetic properties in the as-deposited condition without any post-deposition heat treatment, e.g., Hc∼l-2 Oe and 4πMs∼15–20 kG. The magnetic properties are highly anisotropie in the film plane as the easy-axis M-H loop is square and the hard-axis loop is linear and closed, with the anisotropy field Ha=20–100 Oe. The films exhibit excellent high frequency behavior even in the GHz frequency range which is attributed to the combination of high 4πMs and relatively high Ha.

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Soft Magnetic Properties of [Fe80Ni20-O/NiZn-Ferrite]n Multilayer Thin Films for High Frequency Application

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.488-489.174 ◽

2014 ◽

Vol 488-489 ◽

pp. 174-177

Author(s):

Rui Xu ◽

Lai Sen Wang ◽

Xiao Long Liu ◽

Meng Lei ◽

Qing Luo ◽

...

Keyword(s):

Thin Films ◽

Magnetic Properties ◽

Layer Thickness ◽

High Frequency ◽

Anisotropy Field ◽

Soft Magnetic Properties ◽

Multilayer Thin Films ◽

Insulation Layer ◽

Soft Magnetic ◽

Measured Resistivity

In this research, a series of [Fe80Ni20-O/NiZn-ferritn multilayer thin films with different insulation layer thickness were prepared by magnetron sputtering at room temperature. The high frequency soft magnetic properties of [Fe80Ni20-O/NiZn-ferritn multilayer thin films were investigated. It was found that the in-plane magnetic anisotropy field (Hk) and saturation magnetizations (4πMs) can be adjusted by changing the insulation layer thickness, and the optimal Hk and 4πMs can be obtained as the insulation layer thickness of 2.5 nm. The adjustment of insulation layer thickness is essential to obtain low coercivity (Hc) and high permeability (μ) of the multilayer thin films. The measured resistivity (ρ) of [Fe80Ni20-O/NiZn-ferritn multilayer thin films was increased from 211 to 448 μΩcm with increasing the insulation layer thickness.

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