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

Abstract

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, H c , was found to decrease from 6.5 for 16 to 1.75 Oe for 90 nm. All these results will be discussed and correlated.