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Analytical TEM Examinations of CoPt-TiO2 Perpendicular Magnetic Recording Media

Published online by Cambridge University Press:  19 March 2007

Juliet D. Risner
Affiliation:
Department of Materials Science and Engineering, Stanford University, Stanford, CA 94305-2205, USA
Thomas P. Nolan
Affiliation:
Seagate Media Research Center, Fremont, CA 94538, USA
James Bentley
Affiliation:
Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831-6064
Erol Girt
Affiliation:
Seagate Media Research Center, Fremont, CA 94538, USA
Samuel D. Harkness IV
Affiliation:
Seagate Media Research Center, Fremont, CA 94538, USA
Robert Sinclair
Affiliation:
Department of Materials Science and Engineering, Stanford University, Stanford, CA 94305-2205, USA
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Abstract

For this analytical TEM study, nonmagnetic oxygen-rich boundaries were introduced into Co-Pt-alloy perpendicular recording media by cosputtering Co and Pt with TiO2. Increasing the TiO2 content resulted in changes to the microstructure and elemental distribution within grains and boundaries in these films. EFTEM imaging was used to generate composition maps spanning many tens of grains, thereby giving an overall depiction of the changes in elemental distribution occurring with increasing TiO2 content. Comparing EFTEM with spectrum-imaging maps created by high-resolution STEM with EDXS and EELS enabled both corroboration of EFTEM results and quantification of the chemical composition within individual grain boundary areas. The difficulty of interpreting data from EDXS for these extremely thin films is discussed. Increasing the TiO2 content of the media was found to create more uniformly wide Ti- and O-rich grain boundaries as well as Ti- and O-rich regions within grains.

Type
MATERIALS APPLICATIONS
Copyright
© 2007 Microscopy Society of America

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