A comparative study of the microstructural and magnetic properties of [formula omitted] textured thin polycrystalline Fe 100− xGa x (10 ≤ x ≤ 35) films

Abstract

In this work, we present a detailed analysis of the microstructure and magnetic properties of 50 ± 2 nm thick polycrystalline Fe 100− x Ga x (10 ≤ x ≤ 35) films. Two sets of Fe 100− x Ga x films were fabricated on Si 1 0 0 substrates with and without a forming field H f present. Microstructural properties were studied using X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDS) and conversion electron Mössbauer spectroscopy (CEMS). Magnetic properties were studied using the magneto optical Kerr effect (MOKE) magnetometer. For all films, the 1 1 0 texture normal to the film plane was observed from XRD. No peaks corresponding to the ordered D0 3 or L1 2 phases were observed from XRD. Using CEMS, the disordered A2 phase was confirmed in all films. It was found that the magnetostriction in Set-1 (forming field H f = 0) films was ∼40–50% higher compared to the Set-2 ( H f ≠ 0) films over the whole Ga composition range studied. Both film sets have a strong dependence of saturation field H s on Ga composition. Set-1 films were magnetically isotropic but a weak uniaxial anisotropy was observed in Set-2 films. The saturation field H s in Set-2 films was significantly lower compared to the Set-1 films. It was concluded that the H f reduced H s but also reduced effective saturation magnetostriction constant λ eff in the films.