| AVS 60th International Symposium and Exhibition | |
| Thin Film | Wednesday Sessions |
| Session TF+MI-WeM |
| Session: | Magnetic Thin Films and Nanostructures |
| Presenter: | A. Montgomery, The University of Alabama |
| Authors: | H. Su, The University of Alabama A. Montgomery, The University of Alabama S. Gupta, The University of Alabama |
| Correspondent: | Click to Email |
Granular L10 FePt films are leading candidates for next generation magnetic recording, for instance, heat assisted magnetic recording (HAMR). This is due to its high magnetocrystalline energy constant (~7.0 x 107 erg/cm3), which can maintain thermal stability even with a reduced grain size of 3nm [1]. However, post-deposition annealing at high temperatures or substrate heating during deposition is required to obtain the L10 –phase. Meanwhile, glancing angle deposition (GLAD) is a physical vapor deposition method in which the incoming flux from the source impinges on the substrate at oblique angles, causing increased shadowing and forming nanorods and other nanostructured films [2-5]. Herein we report for the first time the fabrication of FePt, utilizing glancing angle deposition (GLAD) with lower annealing temperatures to obtain L10 phase FePt. The samples were co-sputtered using elemental iron and platinum targets. X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and alternating gradient magnetometry (AGM) were employed to characterize the structural and magnetic properties. SEM micrographs indicated that the nanorods were approximately 12 nm in diameter, the angle between the substrate plane and the growth direction was about 78 degrees, while the lengths of the nanorods varied, depending on deposition time. The angles between the substrate plane and incident flux ranged from 47 degrees to 82 degrees as the substrate presented itself at different angles to the target during the planetary deposition. After annealing, M-H loops showed that the planetary GLAD samples had higher coercivity than that of normally deposited samples. XRD confirms the L10 structure for FePt. Our preliminary results indicate a novel and promising approach to L10-phase FePt for HAMR that is the subject of intense research in the data storage industry.
Acknowledgements
This work was supported by National Science Foundation Grant ECCS-0901858, “GOALI: Nanopatterned Graded Media”. The authors acknowledge the Central Analytical Facility (CAF) and Microfabrication Facility (uamicro)for their support and facilities.
Reference
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