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arXiv · 2203.03496

Understanding the growth of high-aspect-ratio grains in granular L10-FePt thin-film magnetic media

Chengchao Xu·Bing Zhou·Tianxiang Du·B. S. D. Ch. S Varaprasad·David E. Laughlin·JianGang·Zhu
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Abstract

A systematic investigation has been performed to optimize the microstructure of $\mathrm{L1_0-FePt-SiO_x}$ granular thin film as recording media for heat-assisted magnetic recording. The FePt-BN nucleation layer, which is stable even at $700^\circ \text{C}$, is used to control the grain sizes and microstructure during high-temperature processing. The study finds that films of high-aspect-ratio FePt grains with well-formed silicon oxide (SiOx) grain boundaries require the grading of the deposition temperature during film growth as well as the grading of the silicon oxide concentration. Well-isolated columnar grains of $\mathrm{L1_0-FePt}$ with an average height greater than 11 nm and diameters less than 7 nm have been achieved. Transmission electron microscopy (TEM) analysis of the microstructures of samples produced under a variety of non-optimal conditions is presented to show how the microstructure of the films depends on each of the sputtering parameters.

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Chengchao Xu, Bing Zhou, Tianxiang Du, B. S. D. Ch. S Varaprasad, David E. Laughlin, JianGang, Zhu. 2022-03-07. Understanding the growth of high-aspect-ratio grains in granular L10-FePt thin-film magnetic media. https://doi.org/10.1063/5.0089009

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