Texture, microstructure, and magnetic properties of Fe-Co alloy films formed by sputtering at an oblique angle of incidence

Abstract

A study was made of the structure and magnetic properties of Fe-Co alloy films produced by dc magnetron sputtering at an oblique angle of incidence. The films obtained in this manner showed uniaxial magnetic anisotropy in the film plane, with an easy axis of magnetization perpendicular to the incident direction of the sputtered particles. The anisotropy field increased with increasing sputtering gas pressure and with increasing Co content at high pressures. The structure of the film surfaces also changed with sputtering Ar gas pressure, and elongated grains were observed in the intermediate Ar pressure range. The texture was essentially isotropic in the film plane over the whole pressure range. It is suggested that the observed uniaxial anisotropy was due mainly to a magnetoelastic effect.

Negative spin-valve effect inCo65Fe35/Ag/Bellouard1, Rapp2, George3 et al. 1996Phys. Rev. B

“…Oe at 300 K. The origin of such anisotropy in evaporated magnetic layers is usually attributed to anisotropic grains growth or to magnetoelastic effect. 11 We point out that this uniaxial anisotropy has been observed here for amorphous and polycrystalline alloys; it has also been observed for a pure epitaxial metal. 12…”

Microstructures and Soft Magnetic Properties of High Saturation Magnetization Fe-Co-N alloy Thin Films

“…It would be of great scientific as well as technological interests to make this alloy soft while keeping its high saturation magnetization at the same time. However, the extremely high saturation magnetostriction in the Fe-Co alloys, being about 40 ~ 65 × 10 -6 in the composition range of 30 ~ 40 at% of cobalt, makes it very difficult to achieve low coercivity or in-plane uniaxial anisotropy [8][9][10].…”

Magnetic anisotropy in Fe/U and Ni/U bilayers

“…Small peaks in H c and M * r seen around 50 • are likely due to stray fields within the sputtering chamber arising from the magnets within the sputtering guns. It is most likely that the uniaxial anisotropy arises from the off-normal angle of incidence of the sputtered atoms relative to the substrate [29,30].…”