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The influence of Sb doping in achieving high magnetic coercivities in CoPt nanoparticles for micromagnet applications

Published online by Cambridge University Press:  31 January 2011

David E. Mainwaring*
Affiliation:
School of Applied Sciences, Royal Melbourne Institute of Technology, Melbourne 3001, Australia
*
a) Address all correspondence to this author. e-mail: [email protected]
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Abstract

The use of magnetic elements within microelectronic devices are increasingly required in the fabrication of miniature magnetic structures with high energy densities. A synthesis technique is reported that yields Sb-doped CoPt nanoparticles possessing magnetic coercivities as high as 1671 kA/m and magnetic remanences of 295 kA/m, providing an energy product of 20 kJ/m2. Antimony doping was shown to influence the atomic ordering within the alloy sublattices, which allowed the tetragonalization temperature of the nanoparticle structure to be lowered by 200 °C to 400 °C, thereby reducing crystallite growth and sintering during annealing. The “as-synthesized” particles had average diameters of 4.5 nm, which rose to 25 nm on annealing at 600 °C. Synthesis of the doped CoPt particles with high-energy products together with control of particle size distributions in the range of 25 nm allows fabrication of micromagnetic structures by conventional microfabrication techniques such as spin coating and ink-jet printing.

Type
Articles
Copyright
Copyright © Materials Research Society 2009

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