Granular Thin Films with High RF Permeability

Yutaka Shimada, Masahiro Yamaguchi, Sigehiro Ohnuma, Tetsuo Itoh, Wei Dong Li, Sinji Ikeda, Ki Hyeon Kim, H. Nagura

Research output: Contribution to journalArticlepeer-review

74 Citations (Scopus)


Owing to high resistivity and high inplane uniaxial anisotropy, granular films are known to exhibit high permeability at radio frequencies. But this granular resistivity is not high enough to suppress eddy current when they are used at gigahertz frequencies. Recent developments to solve this problem are described. One is patterning the granular films. It is effective to control the inplane anisotropy and to suppress inplane eddy current. Another is deposition of granular films by evaporation. A peculiar fiber structure is formed for which very high resistivity and anisotropy are realized. Finally, a study of using these films as near-field electromagnetic noise absorbers is described, and it is demonstrated that they have high potential as micrometer-scale noise absorbing elements in the gigahertz frequency range.

Original languageEnglish
Pages (from-to)3052-3056
Number of pages5
JournalIEEE Transactions on Magnetics
Issue number5 II
Publication statusPublished - 2003 Sep


  • EMC
  • Granular films
  • Patterned film
  • Permeability

ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials
  • Electrical and Electronic Engineering


Dive into the research topics of 'Granular Thin Films with High RF Permeability'. Together they form a unique fingerprint.

Cite this