HIGH MOMENT SOFT AMORPHOUS COFEZRRE THIN-FILM MATERIALS

CoFeZrRe thin films have been deposited and studied systematically for suitability as a material for thin-film recording heads. The addition of Fe and Re results in a higher degree of crystallinity, thus increasing the coercivity. The addition of Fe increases the magnetostriction of the films while the addition of Re decreases the magnetostriction. The large magnetostriction of films with a large Fe content results in high coercivity. Rotating field annealing is very effective in lowering the coercivity of the magnetostrictive films because of the relaxation of internal stresses. By properly choosing the composition of Fe and Re, we have deposited very soft magnetic thin films with a saturation magnetization of 14 kG, coercivity of 0.3 Oe, and near-zero magnetostriction. The input power dependence of the magnetostriction of this series of films is observed, although x-ray fluorescence analysis does not show any apparent compositional variations. Finally, the anisotropy field of the these films can be decreased by rotating field annealing from 25 to 5 Oe.