Structural and Mössbauer studies of evaporated Fe 100–x Pd x thin films
Résumé
In order to study the influence of palladium atom on structural and hyperfine properties, Fe100–xPdx films (x = 15, 20 and 36 at.%) were deposited by evaporation method onto a Si (1 0 0) substrate. They were then characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD) and conversion electron Mössbauer spectroscopy (CEMS). X-ray diffraction analysis shows the presence of supersaturated solid solution with bcc structure for Pd concentration of 15% and 20%. However, for 36% of Pd, in addition to the supersaturated α-FePd (bcc) phase, another disordered FePd3 phase with fcc structure is present. The grain size did not change with Pd concentration and was about 11 nm, and the lattice parameter increased from 0.287 Å to 0.290 Å with an increasing Pd concentration. The adjustment of Mössbauer spectra confirms the results obtained by X-ray diffraction. Moreover, the Mössbauer spectra have shown that a magnetic texture is present for samples with 20 and 36%. For these Pd concentrations, we believe that a development of an out-of plane magnetic anisotropy occurs in our films.