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

Abstract

Addition of Cu into <i xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">L</i> 1 <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0</sub> -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 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">deg</sup> C. As a result, it is possible to control Curie temperature from 150 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">deg</sup> C to 250 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">deg</sup> 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 <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">55.3</sub> Pt <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">37.5</sub> (Cu) <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">7.2</sub> film exhibited favorable characteristics for the HAMR medium.