Control of Curie Temperature of FePt(Cu) Films Prepared From Pt(Cu)/Fe Bilayers

Addition of Cu into L1₀-ordered FePt alloy thin films with (001) preferential orientation results in the change of Curie temperature. Due to these aspects, the films have potential for next-generation high density perpendicular magnetic recording media, especially, heat-assisted magnetic recording (HAMR) media. FePt(Cu) films were fabricated by annealing Pt(Cu)/Fe bilayers prepared by facing targets sputtering. Their magnetic properties were investigated from room temperature to 300^deg C. As a result, it is possible to control Curie temperature from 150^degC to 250^deg C by changing the amount of Cu in FePt(Cu) films. In addition, we discuss required characteristics of medium for HAMR and mention that the Fe_55.3 Pt_37.5 (Cu)_7.2 film exhibited favorable characteristics for the HAMR medium.