Structural and Magnetic Properties of Exchange Spring type FePt/Fe multilayers

摘要

A series of [FePt(4min)/Fe(t_(Fe))]_(10) multilayers were prepared by RF magnetron sputtering and post annealing. The structures, morphology, composition, and magnetic properties were measured by XRD, SEM, EDX and VSM. X-ray diffraction showed that lattice constants of FePt phase changed with Fe layer thickness and annealing temperature. Both a and c are smaller than the standard values and a decreases as the deposition time of Fe layer increases. The grain sizes of samples annealed at 500°C increase slightly, while those at 600°C increase sharply as Fe layer decreases. The coercivities decrease with the deposition time of Fe layer, and the energy product (BH)_(max) reaches a maximum at Fe layer deposition time of 3 minutes.