https://doi.org/10.1007/s100510050419
Magnetic and transport properties of sputtered Fe/Si multilayers
1
Center of Materials Analysis and National Laboratory of Solid
State Microstructures, Nanjing University, CASTM, Nanjing 210093, P.R. China
2
General Research Institute for Nonferrous Metals,
Beijing, 100088, P.R. China
Corresponding author: a hrzhai@netra.nju.edu.cn
Received:
11
February
1998
Revised:
9
March
1998
Accepted:
9
March
1998
Published online: 15 September 1998
The structural, magnetic and transport properties of sputtered
Fe/Si multilayers were studied. The analyses of the data of the X-ray diffraction, resistance
and magnetic measurements show that heavy atomic interdiffusion between Fe
and Si occurs, resulting in multilayers of different complicated structures
according to different sublayer thicknesses. The nominal Fe layers in the multilayers
generally consist of Fe layers doped with Si, ferromagnetic Fe-Si silicide layers and
nonmagnetic Fe-Si silicide interface layers, while the nominal Si spacers turn out to be
Fe-Si compound layers with additional amorphous Si sublayers only under the condition
either for the series
or
for the series
multilayers. A strong antiferromagnetic (AFM)
coupling and negative magnetoresistance (MR) effect, about 1% , were observed only
in multilayers with iron silicide spacers and disappeared when α-Si layers appear in the
spacers. The dependences of MR on
and on bilayer numbers N resemble the
dependence of AFM coupling. The increase of MR ratio with increasing N is mainly
attributed to the improvement of AFM coupling for multilayers with N. The
dependence
of MR ratio is similar to that in metal/metal system with predominant bulk
spin dependent scattering and is fitted by a phenomenological formula for GMR.
At 77 K both the MR effect and saturation field
increase. All these facts suggest
that the mechanisms of the AFM coupling and MR effect in sputtered Fe/Si multilayers
are similar to those in metal/metal system.
PACS: 72.15.Gd – Galvanomagnetic and other magnetotransport effects / 73.40.Sx – Metal-semiconductor-metal structures
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 1998