The utilization of boron nitride (BN) for granular L1_o-FePt HAMR media fabrication

摘要

In this experimental study, we present a dual-layer structure of FePt-boron nitride (BN)/FePt-SiO_x granular media for the heat-assisted magnetic recording. The boron nitride (BN) was deposited together with FePt at 700 °C for the first 2.5 nm in the initial film growth. After the initial growth, SiO_x was used to replace the BN to serve as the grain boundary material for the rest of film growth process. The transmission electron microscopy study on the fully grown FePt-BN/FePt-SiO_x film shows well-isolated FePt grains that are fully encircled by the well-defined grain boundaries. The areal density of FePt grains is distinctively higher than that of the conventional granular FePt-C-based film at similar film thickness. The FePt-BN/FePt-SiO_x bilayer granular media also demonstrate excellent magnetic properties, which are comparable to that of FePt-C-SiO_x granular media in terms of the hysteresis characteristics.