TY - JOUR
T1 - Magnetic properties and microstructure study of high coercivity Au/FePt/Au trilayer thin films
AU - Chen, S. K.
AU - Yuan, F. T.
AU - Liao, W. M.
AU - Hsu, C. W.
AU - Horng, Lance
PY - 2006/8
Y1 - 2006/8
N2 - High-coercivity Au(60 nm)/FePt(δ nm)/Au(60 nm) trilayer samples were prepared by sputtering at room temperature, followed by post annealing at different temperatures. For the sample with δ=60 nm, L10 ordering transformation occurs at 500 °C. Coercivity (Hc) is increased with the annealing temperature in the studied range 400-800 °C. The Hc value of the trilayer films is also varied with thickness of FePt intermediate layer (δ), from 27 kOe for δ=60 nm to a maximum value of 33.5 kOe for δ=20 nm. X-ray diffraction data indicate that the diffusion of Au atoms into the FePt L10 lattice is negligible even after a high-temperature (800 °C) annealing process. Furthermore, ordering parameter is almost unchanged as δ is reduced from 60 to 15 nm. Transmission electron microscope (TEM) photos indicate that small FePt Ll0 particles are dispersed amid the large-grained Au. We believe that the high coercivity of the trilayer sample is attributed to the small and uniform grain sizes of the highly ordered FePt particles which have perfect phase separation with Au matrix.
AB - High-coercivity Au(60 nm)/FePt(δ nm)/Au(60 nm) trilayer samples were prepared by sputtering at room temperature, followed by post annealing at different temperatures. For the sample with δ=60 nm, L10 ordering transformation occurs at 500 °C. Coercivity (Hc) is increased with the annealing temperature in the studied range 400-800 °C. The Hc value of the trilayer films is also varied with thickness of FePt intermediate layer (δ), from 27 kOe for δ=60 nm to a maximum value of 33.5 kOe for δ=20 nm. X-ray diffraction data indicate that the diffusion of Au atoms into the FePt L10 lattice is negligible even after a high-temperature (800 °C) annealing process. Furthermore, ordering parameter is almost unchanged as δ is reduced from 60 to 15 nm. Transmission electron microscope (TEM) photos indicate that small FePt Ll0 particles are dispersed amid the large-grained Au. We believe that the high coercivity of the trilayer sample is attributed to the small and uniform grain sizes of the highly ordered FePt particles which have perfect phase separation with Au matrix.
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U2 - 10.1016/j.jmmm.2006.01.068
DO - 10.1016/j.jmmm.2006.01.068
M3 - Article
AN - SCOPUS:33646254644
VL - 303
SP - e251-e254
JO - Journal of Magnetism and Magnetic Materials
JF - Journal of Magnetism and Magnetic Materials
SN - 0304-8853
IS - 2 SPEC. ISS.
ER -