Preparation and characterization of electrodeposited Fe/Pt multilayers

Fe(Pt)/Pt(Fe) multilayers have been prepared by single bath technique using pulse deposition under potential control. The Pt-rich layers consist of Pt fcc with some Fe substitution, and the Fe-rich layers exhibit Fe bcc structure. With this multilayer approach the oxygen incorporation, which reaches 30 at.% in homogeneous electrodeposited FePt films, can be significantly reduced. The bilayer thickness as well as the integral composition of the multilayers are adjusted by the pulse durations. Multilayers with an Fe/Pt ratio of 1.0, around 10 at.% O, and a bilayer thickness of about 40 nm are achieved. Annealing these multilayers in hydrogen atmosphere leads to intermixing, formation of the FePt L10 phase and excellent hard magnetic properties.