Magnetic Properties of bcc and bcc-fcc Fe-Pd Alloys Produce by Thermal Evaporation Technique

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Structural and Mössbauer studies of evaporated Fe 100–x Pd x thin films

International audienceIn 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

Microstructure investigation and magnetic study of permalloy thin films grown by thermal evaporation

We study the effect of thickness on the structural and magnetic properties of permalloy thin films, evaporated on glass substrate. The films thicknesses range from 16 to 90 nm. From X-ray diffraction spectra analysis, we show that the thinner films present a ‹1,1,1› preferred orientation. However, the thicker films exhibit a random orientation. The grains size increases and the lattice parameter decreases with increasing thickness. The magnetic force microscopy observations display cross-tie walls features only for the two thicker films (60 and 90 nm thick films). The magnetic microstructure, carried out by Kerr microscopy technique, shows the presence of magnetic domains changing with the direction of applied magnetic field. The coercive field, Hc, was found to decrease from 6.5 for 16 to 1.75 Oe for 90 nm. All these results will be discussed and correlated

Structural and magnetic properties of Ni/Cu bilayers evaporated on CuZn substrate

In this present work we examine the effect of the Ni thickness t (t ranges from 4 to 67 nm) and of the Cu underlayer (with tCu = 27, 52 and 90 nm) on the structural and magnetic properties of Ni/Cu bilayers deposited onto CuZn substrate. The Ni films and the Cu underlayer have been deposited by thermal evaporation. The structural properties were derived from X-ray diffraction experiments. The texture, the strain B ε and the grain size D are studied as a function of Ni thickness. The surface morphology is studied by means of a scanning electron microscope (SEM). The magnetic properties were studied by means of the vibrating sample magnetometer (VSM) and the magneto-optic Kerr effect (MOKE) technique in the longitudinal configuration. The coercive field, the squareness and the saturation field are investigated as a function of Ni thickness. All these results will be discussed and correlated