Magnetic Properties and Annealing Behavior of Electrodeposited NiFeS Thin Films

Zero magnetostrictive films of FeNi with sulfur contents up to ∼6.5% by weight were prepared by electrodeposition from electrolytes containing thiourea. The total sulfur content in the films increased linearly with thiourea coacentration. The Hc varied from about 10 Oe for no thiourea, down through a broad minimum of about 4 Oe at intermediate thiourea concentrations. The dispersion α90 also went through a broad minimum in this range; values as low as 1° were obtained. Hk was constant at 2.95±0.1 Oe above ∼1% sulfur. The effects of thiourea on Hc, Hk, and α90 are interpreted in terms of its influence on crystallite size and shape, on the smoothness of the film, on the impurity content, and on the planar stresses in the film. With this electrolyte, film compositions were constant throughout their thickness to ±0.2% Ni. Exposure of these films to 60°C in a saturating field parallel to their easy axis produced no changes in Hc, Hk, or α90 for times up to 2000 min. In a transverse field, the change in propert...