Hostname: page-component-78c5997874-fbnjt Total loading time: 0 Render date: 2024-11-05T11:21:09.726Z Has data issue: false hasContentIssue false

HRTEM and EELS Studies of Py/Al and Co/Al Multilayers

Published online by Cambridge University Press:  21 March 2011

Jiaming Zhang
Affiliation:
Department of Chemical Engineering and Materials Science, Michigan State University, East Lansing, MI, 48824
Martin A. Crimp
Affiliation:
Department of Chemical Engineering and Materials Science, Michigan State University, East Lansing, MI, 48824
N. Theodoropoulou
Affiliation:
Department of Physics and Astronomy, Michigan State University, East Lansing, MI, 48824
A. Sharma
Affiliation:
Department of Physics and Astronomy, Michigan State University, East Lansing, MI, 48824
R. Loloee
Affiliation:
Department of Physics and Astronomy, Michigan State University, East Lansing, MI, 48824
W. P. Pratt Jr
Affiliation:
Department of Physics and Astronomy, Michigan State University, East Lansing, MI, 48824
J. Bass
Affiliation:
Department of Physics and Astronomy, Michigan State University, East Lansing, MI, 48824
Get access

Abstract

Ferromagnetic/non-magnetic (F/N) metallic multilayers in the Current-Perpendicular-to-Plane (CPP) geometry show giant Magnetoresistance (MR) and are promising candidates for potential use in high density storage devices. F/Al interfaces were recently shown to have large interface specific resistances that enhance the CPP-resistance. However, the CPP resistances showed instability over time at room temperature and also upon annealing to 453K. To help understand both the large interface specific resistances and their instabilities, we have undertaken cross-sectional High Resolution Transmission Electron Microscopy (HRTEM) and Electron Energy Loss Spectroscopy (EELS) studies of both as-sputtered and annealed Py/Al and Co/Al multilayers. We find well-layered, but rough structures with local F/Al interfaces being tilted up to ˜15°from the plane perpendicular to the growth direction. HRTEM images appear to show diffuse interfaces, but a through-focus series of images suggests considerable grain overlap in the electron beam direction, thereby complicating interpretation. This combination of HRTEM imaging and EELS analysis suggests that any interfacial mixing is limited in scale, and shows no evidence of intermetallic compound formation. No obvious differences are seen between assputtered and annealed samples.

Type
Research Article
Copyright
Copyright © Materials Research Society 2007

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

1. Theodoropoulou, N., Sharma, A., Loloee, R., Pratt, W.P. Jr, Bass, J., Fert, A., and Jaffres, H, J. Appl. Phys. 99, 08G502 (2006)Google Scholar
2. Theodoropoulou, N., Sharma, A. Haillard, T., Loloee, R., Pratt, W.P. Jr, Bass, J., Zhang, J. and Crimp, M.A., IEEE Transactions on Magnetics (in press)Google Scholar
3. Massalski, T.B., Okamoto, H., Subramanian, P.R., and Kacprzak, L., Binary alloy phase diagrams. Vol.2. 1990, Metals Park, OH: ASM International.Google Scholar
4. Vovk, V., Schmitz, G., and Kirchheim, R., Phys. Rev. B 69, 104102 (2004).Google Scholar
5. Lee, S.F. et al., Phys. Rev. B 52, 15426 (1995).Google Scholar
6. Dang, K. Le, Veillet, P., Vélu, E., Parkin, S. S. P., and Chappert, C., Appl. Phys. Lett. 63, 108 (1993).Google Scholar
7. Ahn, C. C., Transmission Electron Energy Loss Spectrometry in Materials Science and the EELS ATALS, 2nd ed. (WILEY-VCH, 2004).Google Scholar