Magnetic Properties and Microstructure of the Granular Films Processed by Annealing FePt-Based Multilayers

摘要

To explore the possibility of FePt-based soft/hard nanocomposite magnets, granular films were prepared by annealing Pt/Fe, FePt/Fe, and FePt/Fe{sub}3Pt multilayers. Although a high coercivity of 12 kOe was obtained by annealing the Fe{sub}3Pt/FePt multilayers, only a small re-manence was obtained due to random orientation of L1{sub}0 FePt grains. By introducing oxygen during the film deposition, a few nanometer oxide particles were observed within the FePt grains and H{sub}c increased at the expense of M{sub}r. A possible way to achieve a higher value of (-BH)max is discussed based on the relationship between the microstructure and magnetic properties.