R&D: Utilization of Boron Nitride for Granular L10-FePt HAMR Media Fabrication

Applied Physics Letters has published an article written by Bing Zhou, Data Storage Systems Center, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, USA, and Materials Science and Engineering Department, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, USA, David E. Laughlin, and Jian-gang (Jimmy) Zhu, Data Storage Systems Center, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, USA, and Materials Science and Engineering Department, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, USA, and Electrical and Computer Engineering Department, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, USA.

Abstract: “In this experimental study, we present a dual-layer structure of FePt-boron nitride (BN)/FePt-SiOx 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, SiOx 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-SiOx 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-SiOx bilayer granular media also demonstrate excellent magnetic properties, which are comparable to that of FePt-C-SiOx granular media in terms of the hysteresis characteristics.“

This research was funded in part by the Data Storage Systems Center at Carnegie Mellon University and all its industrial sponsors and by the Kavcic-Moura Fund at Carnegie Mellon University. The authors acknowledge the use of the Materials Characterization Facility at Carnegie Mellon University supported by Grant No. MCF-677785.