FePtCu alloy thin films: Morphology, L1{sub 0} chemical ordering, and perpendicular magnetic anisotropy

Journal Article · Mon Oct 01 00:00:00 EDT 2012 · Journal of Applied Physics

DOI:https://doi.org/10.1063/1.4757038· OSTI ID:22089478

Brombacher, C.; Schletter, H.; Daniel, M.; Matthes, P.; Joehrmann, N.; Makarov, D.; Hietschold, M.; Albrecht, M. ^[1]; Maret, M. ^[2]

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1. Institute of Physics, Chemnitz University of Technology, D-09107 Chemnitz (Germany)
2. Laboratory of Science and Engineering of Materials and Processes (SIMaP), INP-Grenoble/CNRS/UJF, F-38402 Saint-Martin d'Heres (France)

Rapid thermal annealing was applied to transform sputter-deposited Fe{sub 51}Pt{sub 49}/Cu bilayers into L1{sub 0} chemically ordered ternary (Fe{sub 51}Pt{sub 49}){sub 100-x}Cu{sub x} alloys with (001) texture on amorphous SiO{sub 2}/Si substrates. It was found that for thin film samples, which were processed at 600 Degree-Sign C for 30 s, the addition of Cu strongly favors the L1{sub 0} ordering and (001) texture formation. Furthermore, it could be revealed by transmission electron microscopy and electron backscatter diffraction that the observed reduction of the ordering temperature with Cu content is accompanied by an increased amount of nucleation sites forming L1{sub 0} ordered grains. The change of the structural properties with Cu content and annealing temperature is closely related to the magnetic properties. While an annealing temperature of 800 Degree-Sign C induces strong perpendicular magnetic anisotropy (PMA) in binary Fe{sub 51}Pt{sub 49} films, the addition of Cu systematically reduces the PMA. However, due to the enhancement of both the A1-L1{sub 0} phase transformation and the development of the (001) texture with increasing Cu content, lowering of the annealing temperature leads to a shift of the maximum perpendicular magnetic anisotropy towards alloys with higher Cu content. Thus, for an annealing temperature of 600 Degree-Sign C, the highest perpendicular magnetic anisotropy energy is found for the (Fe{sub 51}Pt{sub 49}){sub 91}Cu{sub 9} alloy. The smooth surface morphology, adjustable PMA, and high degree of intergranular exchange coupling make these films suitable for post-processing required for specific applications such as for sensorics or magnetic data storage.

• OSTI ID: 22089478
• Journal Information: Journal of Applied Physics, Vol. 112, Issue 7; Other Information: (c) 2012 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); ISSN 0021-8979
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ANISOTROPY
ANNEALING
BACKSCATTERING
COPPER COMPOUNDS
COUPLING
CRYSTALS
DIFFRACTION
IRON COMPOUNDS
LAYERS
MAGNETIC PROPERTIES
PLATINUM COMPOUNDS
SILICON OXIDES
SUBSTRATES
SURFACES
TERNARY ALLOY SYSTEMS
TEXTURE
THIN FILMS
TRANSMISSION ELECTRON MICROSCOPY