Development and application of fluoride-based nanogranular films with ultra-high resistivity

2014 Fiscal Year Final Research Report

• Project/Area Number: 24560388
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Electronic materials/Electric materials
• Research Institution: Research Institute for Electromagnetic Materials
• Principal Investigator: OHNUMA Shigehiro 公益財団法人電磁材料研究所, その他部局等, 研究員 (50142633)
• Co-Investigator(Kenkyū-buntansha): MASUMOTO Hiroshi 東北大学, 学際科学フロンティア研究所, 教授 (50209459) ; NAOE Masayuki 公益財団法人電磁材料研究所, 主任研究員 (50533725)
• Project Period (FY): 2012-04-01 – 2015-03-31
• Keywords: ナノグラニュラー軟磁性膜 / フッ化物 / 比抵抗 / 一軸異方性 / 異方性磁界 / 複素透磁率 / 強磁性共鳴 / 高周波磁気応用

Outline of Final Research Achievements

This study is of the development of ultra-high resistive nanogranular soft magnetic films for GHz frequency region. The films, consisting of CoPd-alloy-based magnetic metals and fluoride matrices, were prepared by tandem-sputtering deposition as a novel method for the films. It was clarified that calcium fluoride behaves the best insulation matrix, attributing to its wide energy band gap and great crystallinity. Furthermore, some films exhibited higher ferromagnetic resonance frequency with great in-plane uniaxial anisotropy more than 1.4 times compared with conventional films owing to twice anisotropy field. This superior anisotropy being independent of the induced field was given only by substrate motion of the tandem sputtering. Nanostructure analyses demonstrated innovative orientations of the nanogranules as for the Random Anisotropy Model for soft nanomagnetic materials. These results brought some steps closer to realization of the practical materials for GHz applications.

Free Research Field

ナノグラニュラー膜