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Elemental Distribution in Multilayer Systems by Laser-Assisted Atom Probe Tomography with Various Analysis Directions

Published online by Cambridge University Press:  16 September 2015

Masaki Kubota ,
Hisashi Takamizawa ,
Yasuo Shimizu ,
Yasuko Nozawa ,
Naoki Ebisawa ,
Takeshi Toyama ,
Yoichi Ishida ,
Katsuaki Yanagiuchi ,
Koji Inoue  and
Yasuyoshi Nagai
Masaki Kubota
Affiliation:
TDK Corporation, 543 Otai, Saku-shi, Nagano 385-8555, Japan
Hisashi Takamizawa
Affiliation:
The Oarai Center, Institute for Materials Research, Tohoku University, Oarai, Ibaraki 311-1313, Japan
Yasuo Shimizu
Affiliation:
The Oarai Center, Institute for Materials Research, Tohoku University, Oarai, Ibaraki 311-1313, Japan
Yasuko Nozawa
Affiliation:
The Oarai Center, Institute for Materials Research, Tohoku University, Oarai, Ibaraki 311-1313, Japan
Naoki Ebisawa
Affiliation:
The Oarai Center, Institute for Materials Research, Tohoku University, Oarai, Ibaraki 311-1313, Japan
Takeshi Toyama
Affiliation:
The Oarai Center, Institute for Materials Research, Tohoku University, Oarai, Ibaraki 311-1313, Japan
Yoichi Ishida
Affiliation:
TDK Corporation, 543 Otai, Saku-shi, Nagano 385-8555, Japan
Katsuaki Yanagiuchi*
Affiliation:
TDK Corporation, 543 Otai, Saku-shi, Nagano 385-8555, Japan
Koji Inoue
Affiliation:
The Oarai Center, Institute for Materials Research, Tohoku University, Oarai, Ibaraki 311-1313, Japan
Yasuyoshi Nagai
Affiliation:
The Oarai Center, Institute for Materials Research, Tohoku University, Oarai, Ibaraki 311-1313, Japan
*
*Corresponding author. [email protected]
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Abstract

Elemental distributions in a magnetic multilayer system with the structure Si substrate/Ta/NiFe/Ru/CoFeB/Ru/NiFe were studied using atom probe tomography (APT) along different analysis directions. The distributions of Ru and B atoms, which require a high evaporation field, were strongly influenced by the APT analysis direction. In particular, B in the CoFeB layer appeared near the interface with the lower Ru layer when the analysis was anti-parallel to the film growth direction, while B atoms were observed at the other side of the CoFeB layer when the analysis was parallel to the film growth direction. Moreover, when the analysis was perpendicular to the film growth direction, a homogenous distribution of B atoms was found within the CoFeB layer. Owing to this B behavior, the underlying Ru layer was affected in both of these analysis directions. In APT measurements of such a multilayer system composed of a stack of different evaporation field materials, evaluation of the elemental distribution around interfaces should be performed from more than one analysis direction.

Keywords

magnetic multilayersatom probe tomographyfield evaporationartifact
Type
Materials Applications and Techniques
Information
Microscopy and Microanalysis , Volume 21 , Issue 6 , December 2015 , pp. 1373 - 1378
Copyright
© Microscopy Society of America 2015 

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