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arXiv · 2303.11411

Bias sputtering of granular $\text{L1}_0$-FePt films with hexagonal boron nitride grain boundaries

Chengchao Xu·B. S. D. Ch. S Varaprasad·David E. Laughlin·Jian-Gang·Zhu
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Abstract

In this paper, we present an experimental study of $\text{L1}_0$-FePt granular films with crystalline/amorphous boron nitride (BN) grain boundary materials for heat assisted magnetic recording (HAMR). It is found that an adequate RF substrate bias yields the formation of hexagonal boron nitride (h-BN) nanosheets in grain boundaries, facilitating the columnar growth of FePt grains during sputtering at high temperatures. The h-BN monolayers conform to the side surfaces of columnar FePt grains, completely encircling individual FePt grains. The resulting core-shell FePt/h-BN nanostructures appear to be highly promising for HAMR application. The high thermal stability of h-BN grain boundaries allows the deposition temperature to be as high as 800oC such that high order parameters of FePt $\text{L1}_0$ phase have been obtained. For the fabricated FePt/h-BN thin film, excellent granular microstructure with FePt grains of 6.5nm in diameter and 11.5nm in height has been achieved along with good magnetic hysteresis properties.

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BibTeXRIS

Chengchao Xu, B. S. D. Ch. S Varaprasad, David E. Laughlin, Jian-Gang, Zhu. 2023-03-20. Bias sputtering of granular $\text{L1}_0$-FePt films with hexagonal boron nitride grain boundaries. https://doi.org/10.1038/s41598-023-38106-9

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