Takaharu Yonemoto

Mössbauer spectra and structures of Fe/Fe-N multilayered films formed by Fe sputtering and ECR nitrogen plasma exposure

Abstract Fe/Fe-N multilayered films were prepared by an alternation of Fe sputtering and Electron Cyclotron Resonance (ECR) nitrogen plasma exposure, and the films were investigated by 57 Fe Conversion Electron Mossbauer Spectroscopy (CEMS). ECR nitrogen plasma exposure of the sputtered Fe layers generated fine crystal ϵ-Fe 2-3 N and Fe 2 N grains, rather than thermally stable γ′-Fe 4 N. The Fe/Fe-N multilayered films has a periodic structure of [α-Fe]/[ϵ-Fe 2-3 N and Fe 2 N], and showed good soft magnetic properties.

Magnetic properties of Fe‐Zr‐Co/Fe‐Zr‐Co‐N multilayered films

Fe‐Zr‐Co/Fe‐Zr‐Co‐N soft magnetic multilayered films were alternately prepared by Fe‐Zr‐Co alloy sputtering and electron cyclotron resonance plasma nitridation, and their magnetic properties and thermal stability were investigated. Co addition to Fe‐Zr/Fe‐Zr‐N multilayered films was effective in improving the magnetic properties of these films. The soft magnetic properties of these films demonstrated outstanding thermal stability, and it was observed that the hyperfine field Hint increased up to that for pure Fe‐Co alloy by heat treatment. Under the optimum preparation conditions, values for saturation flux density Bs of 2.02–2.06 T, coercivity Hc of 75–90 A/m, and relative permeability μ’≥3100 (at 20 MHz) were obtained in Fe84Zr8Co8/Fe84Zr8Co8‐N and Fe76Zr8Co16/Fe76Zr8Co16‐N multilayered films after annealing at 873 K for 3.6 ks.

Magnetic properties of Fe/Fe-N and Fe/Cu-N multilayered films having intermediate layers containing nitrogen

The structures and magnetic properties of Fe/Fe-N and Fe/Cu-N multilayered films having intermediate layers containing nitrogen were investigated. Fe/Fe-N films formed by alternate Fe sputtering and electron cyclotron resonance (ECR) nitrogen plasma exposure had Fe layers containing approximately 3 at% nitrogen, the /spl alpha/-Fe(110) lattice spacing being larger than that of pure iron. This expansion of the /spl alpha/-Fe(110) lattice spacing was observed after Fe deposition. The Fe layers containing a little nitrogen improved the soft magnetic properties. Fe/Cu-N multilayered films formed by the alternation of Fe sputtering and Cu-N nitrogen reactive sputtering also showed expansion of the /spl alpha/-Fe(110) lattice spacing and reduction of the Fe crystallite size with increasing partial N/sub 2/ gas pressure (PN/sub 2/) during Cu-N reactive sputtering. The Fe/Cu-N multilayered films achieved minimum coercivity at PN/sub 2/=7%. >