Control of Size and Magnetic Properties of L1$_{0}$ FePt islands by DC sputtering

ORAL

Abstract

FePt particles with the tetragonal L1$_{0}$ structure are attractive for high density recording media. In this study, we have fabricated well-ordered and separated L1$_{0}$ FePt islands on MgO (100) substrates by DC sputtering at temperatures varying from room temperature to 700 $^{\circ}$C. The dependence of particle size, degree of ordering and magnetic properties on sputtering time (5-20s), power (5-20W) and substrate temperature (300-1000K) were investigated. Electron diffraction patterns from TEM showed that the islands had the L1$_{0}$ tetragonal structure. TEM data revealed that a higher substrate temperature significantly increased the size of the islands from 2 to 20 nm whereas a higher sputtering power and longer sputtering times did not change the island size much but made the islands more connected with each other. Larger size islands and inter-connected islands showed a higher degree of ordering with an ordering parameter of 0.8 achieved at 600 $^{\circ}$C. The magnetic properties are currently being measured and the results will be reported.

*Work is supported by DOE ARPA-E DE-AR0000046.

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Authors

  • Xiaocao Hu

    • Department of Materials Science and Engineering, University of DE, Newark, DE, 19716, USA

  • Ozan Akdogan

    • Department of Physics and Astronomy, University of DE, Newark, DE, 19711, USA
    • Department of Physics and Astronomy, University of DE, Newark, DE, 19711 USA
    • Department of Physics and Astronomy, University of DE, Newark, DE, 19716, USA

  • Wanfeng Li

    • Department of Physics and Astronomy, University of DE, Newark, DE, 19716, USA

  • George Hadjipanayis

    • Department of Physics and Astronomy, University of Delaware, Newark, DE, U.S.A.
    • Department of Physics and Astronomy, University of DE, Newark, DE, 19711, USA
    • Department of Physics and Astronomy, University of DE, Newark, DE, 19716, USA
    • University of Delaware