The effect from thickness of an intermediate copper layer in nanosized Fe50Pt50 (15 nm)/Cu (x)/Fe50Pt50 (15 nm) (x = 7.5, 15, and 30 nm) composite films on SiO2 (100 nm)/Si(001) substrates on the diffusion-controlled phase formation processes—transformation of the disordered magnetically soft A1(FePt) phase into the ordered magnetically hard L10(FePt) phase during annealing in vacuum—is studied by physical materials science methods: X-ray diffraction and measurement of magnetic properties. The A1(FePt) phase forms in all films during deposition. Annealing in vacuum in the temperature range 300–900°C is accompanied by thermally activated diffusion processes between the Cu and FePt layers. When thickness of the intermediate Cu layer increases from 7.5 nm up to 15 nm, the onset temperature of A1(FePt) → L10(FePt) phase transformation raises by 100°C, i.e., to 800°C. Simultaneously, the coercivity in films decreases since Cu dissolves in the FePt lattice.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Mark H. Kryder, “Future storage technologies: a look beyond the horizon,” in: Proc. Symp. Computerworld’s Storage Networking World Conference (April 3–6, 2006, San Diego, California, USA), San Diego (2006), pp. 350–358.
M. Albrecht and C. Brombacher, “Rapid thermal annealing of FePt thin films,” Phys. Status Solidi A, 210, 1–10 (2013).
O. P. Pavlova, T. I. Verbitska, I. A. Vladymyrskyi, et al., “Structural and magnetic properties of annealed FePt/Ag/FePt thin films,” Appl. Surf. Sci., 266, 100–104 (2013).
Liwang Liu, Wei Sheng, Jianmin Bai, et al., “Magnetic properties and magnetization reversal process of L10FePt/Fe bilayers magnetic thin films,” Appl. Surf. Sci., 258, 8124–8127 (2012).
Utsumiya Kazutoshi, Seki Takeshi, and Takanashi Koki, “Magnetic properties of L10-FePt/permalloy exchange-spring films,” J. Appl. Phys., 110, 103911-1–4 (2011).
Y. S. Yu, Hai-Bo Li, W. L. Li, et al., “Low-temperature ordering of L10FePt phase in FePt thin film with AgCu underlayer,” J. Magn. Magn. Mater., 320, L125–L128 (2008).
Chun Feng, Qian Zhan, Baone Li, et al., “Magnetic properties and microstructure of FePt/Au multilayers with high perpendicular magnetocrystalline anisotropy,” Appl. Phys. Lett., 93, 152513-1–3 (2008).
B. Wang, K. Barmak, and T. J. Klemmer, “A1 to L10 transformation in FePt films with ternary alloying additions of Ag and Au,” IEEE Trans. Magn., 46, No. 6, 1773–1776 (2010).
W. Y. Zhang, H. Shima, F. Takano, et al., “Enhancement in ordering of Fe50Pt50 film caused by Cr and Cu additives,” J. Appl. Phys., 106, 033907-1–4 (2009).
K. Barmak, J. Kim, L. H. Lewis, et al., “On the relationship of magnetocrystalline anisotropy and stoichiometry in epitaxial L10CoPt(001) and FePt(001) thin films,” J. Appl. Phys., 98, 033904-1–33 (2005).
A. C. Sun, F. T. Yuan, and Jen-Hwa Hsu, “Control of growth and ordering process in FePt(001) film at 300°C,” J. Phys. Conf. Ser., 200, 1020099-1–4 (2010).
Tomoyuki Maeda, Tadashi Kai, Akira Kikitsu, et al., “Reduction of ordering temperature of an FePt-ordered alloy by addition of Cu,” Appl. P hys. Lett., 80, No. 12, 2147–2149 (2011).
Acknowledgment
The authors are grateful to staff of the surface and interface physics team at the Chemnitz University of Technology (Germany)), including Professor M. Albrecht and Doctor G. Beddis, for making the samples, assisting in the research, and discussing the results.
Author information
Authors and Affiliations
Corresponding author
Additional information
Translated from Poroshkovaya Metallurgiya, Vol. 55, Nos. 1–2 (507), pp. 141–146, 2015.
Rights and permissions
About this article
Cite this article
Verbitskaya, T.I., Figurnaya, E.V., Verbitskaya, M.Y. et al. Effect of Copper on the Formation of Ordered L10(FePt) Phase in Nanosized Fe50Pt50/Cu/Fe50Pt50 Films on SiO2/Si (001) Substrates. Powder Metall Met Ceram 55, 109–113 (2016). https://doi.org/10.1007/s11106-016-9785-0
Received:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s11106-016-9785-0