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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: david.mainwaring@rmit.edu.au
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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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References

REFERENCES

1.Wang, N., Bowers, B.J., Arnold, D.P.: Wax-bonded NdFeB micromagnets for microelectromechanical systems applications. J. Appl. Phys. 103, 07E109 1(2008)Google Scholar
2.Cavallotti, P.L., Bestetti, M., Franz, S.: Microelectrodeposition of Co/Pt alloys for micromagnetic applications. Electrochim. Acta 48, 3013 (2003)CrossRefGoogle Scholar
3.Gutfleisch, O., Dempsey, N.M.: High performance μ-magnets for microelectromechanical systems (MEMS)Magnetic Nanostructures in Modern Technology edited by B. Azzerboni, G. Asti, L. Pareti, and M. Ghidini (Springer, Dordrecht The Netherlands 2008)167194CrossRefGoogle Scholar
4.Castaldi, L., Giannakopoulos, K., Travlos, A., Niarchos, D., Boukari, S., Beaurepaire, E.: FePt and CoPt nanoparticles co-deposited on silicon dioxide-a comparative study. Nanotechnology 19, 085701 (2008)Google Scholar
5.Weller, D., Moser, A., Folks, L., Best, M.E., Le, W., Toney, M.F., Schweickert, M., Thiele, J-L., Doerner, M.F.: High Ku materials approach to 100 Gbits/in2. IEEE Trans. Magn. 36, 10 (2000)CrossRefGoogle Scholar
6.Hadjipanayis, G.C., Marinescu, M., Huang, Y.H., Bonder, M.J., Gabay, A.: Magnetic meta-materials for high-technology applications. Sens. Lett. 5, 1 (2007)Google Scholar
7.Jiang, Z., Llandro, J., Mitrelias, T., Bland, J.A.C.: An integrated microfluidic cell for detection, manipulation, and sorting of single micron-sized magnetic beads. J. Appl. Phys. 99, 08S1051(2006)Google Scholar
8.Kumar, S., Zou, S.: Electroreduction of O2 on uniform arrays of Pt and PtCo nanoparticles. Electrochem. Commun. 8, 1151 (2006)Google Scholar
9.Akinaga, H.: Magnetoresistive switch effect in metal/semiconductor hybrid granular films—Extra huge magnetoresistance effect at room temperature. J. Magn. Magn. Mater. 239, 145 (2002)CrossRefGoogle Scholar
10.Arnold, D.P.: Review of microscale magnetic power generation. IEEE Trans. Magn. 43, 3940 (2007)Google Scholar
11.Cugat, O., Delamare, J., Reyne, G.: Magnetic microsystems—MAG-MEMSMagnetic Nanostructures in Modern Technology edited by B. Azzerboni, G. Asti, L. Pareti, and M. Ghidini (Springer, Dordrecht The Netherlands 2008)105125Google Scholar
12.Sun, S., Murray, C.B., Weller, D., Folks, L., Moser, A.: Monodisperse FePt nanoparticles and ferromagnetic FePt nanocrystal superlattices. Science 287, 1989 (2000)CrossRefGoogle ScholarPubMed
13.Schaak, R.E., Sra, A.K., Leonard, B.M., Cable, R.E., Bauer, J.C., Han, Y-F., Means, J., Teizer, W., Vasquez, Y., Funck, E.S.: Metallurgy in a beaker: Nanoparticle toolkit for the rapid low-temperature solution synthesis of functional multimetallic solid solution materials. J. Am. Chem. Soc. 127, 3506 (2005)Google Scholar
14.Tanase, M., Zhu, J-G., Liu, C., Shukla, N., Klemmer, T.J., Weller, D., Laughlin, D.E.: Structure optimization of FePt nanoparticles of various sizes for magnetic data storage. Metall. Mater. Trans. A 38, 798 (2007)CrossRefGoogle Scholar
15.Klem, M.T., Willits, D., Solis, D.J., Belcher, A.M., Young, M., Laughlin, D.E.: Bio-inspired synthesis of protein-encapsulated CoPt nanoparticles. Adv. Funct. Mater. 15, 1489 (2005)CrossRefGoogle Scholar
16.Tzitzois, V., Niarchos, D., Margariti, G., Fidler, J., Petridis, D.: Synthesis of CoPt nanoparticles by a modified polyol method: Characterisation and magnetic properties. Nanotechnology 16, 287 (2005)Google Scholar
17.Park, J., Cheon, J.: Synthesis of “solid solution” and “core-shell” type cobalt-platinum magnetic nanoparticles via transmetalation reactions. J. Am. Chem. Soc. 123, 5743 (2001)CrossRefGoogle ScholarPubMed
18.Hussein, A.S., Murugaraj, P., Rix, C.J., Mainwaring, D.E.: Role of particle size and crystal microstructure on the magnetic behavior of binary alloy nanoparticlesNanotechnology and its Applications, First Sharjah International Conference Nanotechnology and Its Applications edited by Y.I. Salamin, H. Al-Awadhi, N.M. Jisrawi, and N. Tabet(AIP Conference Proceedings 929, American Institute of Physics Melville, NY 2007)117122Google Scholar
19.Kitakami, O., Shimada, Y., Oikawa, K., Daimon, H., Fukamichi, K.: Low-temperature ordering of L10-CoPt thin films promoted by Sn, Pb, Sb, and Bi additives. Appl. Phys. Lett. 78, 1104 (2001)Google Scholar
20.Chen, C., Kitakami, O., Okamoto, S., Shimada, Y.: Ordering and orientation of CoPt/SiO2 granular films with additive Ag. Appl. Phys. Lett. 76, 3218 (2000)Google Scholar
21.Min, J.H., An, B.H., Cho, J.U., Ji, H.M., Noh, S.J., Kim, Y.K., Liu, H.L., Wu, J.H., Ko, Y-D., Chung, J-S.. Effects of Cu doping on the microstructure and magnetic properties of CoPt nanowires. J. Appl. Phys. 101, 09K5131(2007)Google Scholar
22.Wang, H., Yang, F.J., Xue, S.X., Mo, Q., Wang, H.B., Li, Q., Li, Z.Y.: Structure and magnetic properties of CoPtCu:Ag nanocomposite films with (001) texture. Appl. Phys. A 88, 775 (2007)CrossRefGoogle Scholar
23.Kang, S.S., Nikles, D.E., Harrell, J.W.: Synthesis, chemical ordering, and magnetic properties of self-assembled FePt–Ag nanoparticles. J. Appl. Phys. 93, 7178 1 (2003)Google Scholar
24.Yan, Q.Y., Kim, T., Purkayastha, A., Xu, Y., Shima, M., Gambino, R.J., Ramanatha, G.: Magnetic properties of Sb-doped FePt nanoparticles. J. Appl. Phys. 99, 08N7091(2006)Google Scholar
25.Pileni, M.P.: Reverse micelles as microreactors. J. Phys. Chem. 97, 6961 (1993)CrossRefGoogle Scholar
26.Pileni, M.P.: Nanosized particles made in colloidal assemblies. Langmuir 13, 3266 (1997)Google Scholar
27.Azaroff, L.V., Buerger, M.J.: The Powder Method in X-Ray Crystallography(McGraw-Hill Book Company New York 1958)254265Google Scholar
28.di Vece, M., Grandjean, D., Van Bael, M.J., Romero, C.P., Wang, X., Decoster, S., Vantomme, A., Lievens, P.. Hydrogen-induced Ostwald ripening at room temperature in a Pd nanocluster film. Phys. Rev. Lett. 100, 236105 (2008)Google Scholar
29.JCPDF-OCDD No. 72-11440 (PtSb) and JCPDF-OCDD No. 22-1206 (Pt3Sb2). International Center for Diffraction Data: Newton Square, PAGoogle Scholar
30.Voigtlander, B., Zinner, A., Weber, T., Bonzel, H.P.: Modification of growth kinetics in surfactant-mediated epitaxy. Phys. Rev. B 51, 7583 (1995)CrossRefGoogle ScholarPubMed
31. JCPDF-OCDD No. 43-1358 (CoPt). International Center for Diffraction Data Newton Square, PAGoogle Scholar
32.Roberts, B.W.: X-ray measurement of order in CuAu. Acta Metall. 2, 597 (1954)CrossRefGoogle Scholar
33.Yan, Q., Kim, T., Purkayastha, A., Ganesan, P.G., Sinha, M., Ramnath, G.: Enhanced chemical ordering and coercivity in FePt alloy nanoparticles by Sb-doping. Adv. Mater. 17, 2233 (2005)Google Scholar
34.Razee, S.S.A., Staunton, J.B., Ginatempo, B., Bruno, E., Pinski, F.J.: On the relationship of high coercivity and L10 ordered phase in CoPt and FePt thin films. Phys. Rev. B 64, 014411 1 (2001)CrossRefGoogle Scholar
35.Stoner, E.C., Wohlfarth, E.P.: A mechanism of magnetic hysteresis in heterogeneous alloys. Phil. Trans. Roy. Soc. A 240, 599 (1948)Google Scholar