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Two sets of (Mg,Y)-doped BaTiO3 samples were prepared to investigate the effects of the core/shell volumetric ratio on the dielectric-temperature behavior of BaTiO3: one set with samples of the same grain size but different core sizes and the other with samples of the same core size but different shell thicknesses. The microstructural variation of the samples was characterized and their dielectric properties were measured. For both sets of samples, the temperature stability of the dielectric properties was generally improved with a reduction of the volumetric shell ratio regardless of the grain and core sizes. There existed, however, a limit of the reduction; for the studied range, shell thickness of one third of the core radius appeared to be an optimum thickness for the given amounts of dopants. It was concluded that the volumetric shell ratio should be optimized so as not to exceed a specific limit, for our case two thirds of the grain volume, to secure temperature stability of the dielectric properties of BaTiO3.


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Effects of core/shell volumetric ratio on the dielectric-temperature behavior of BaTiO3

Show Author's information Sang-Chae JEONaByung-Kwon YOONbKwan-Hyeong KIMbSuk-Joong L. KANGa( )
Materials Interface Laboratory, Department of Materials Science and Engineering, Korea Advanced Institute of Science and Technology, 291 Daehak-ro, Yuseong-gu Daejeon 305-701, Korea
LCR Division, Samsung Electro-Mechanics, Suwon 443-743, Korea

Abstract

Two sets of (Mg,Y)-doped BaTiO3 samples were prepared to investigate the effects of the core/shell volumetric ratio on the dielectric-temperature behavior of BaTiO3: one set with samples of the same grain size but different core sizes and the other with samples of the same core size but different shell thicknesses. The microstructural variation of the samples was characterized and their dielectric properties were measured. For both sets of samples, the temperature stability of the dielectric properties was generally improved with a reduction of the volumetric shell ratio regardless of the grain and core sizes. There existed, however, a limit of the reduction; for the studied range, shell thickness of one third of the core radius appeared to be an optimum thickness for the given amounts of dopants. It was concluded that the volumetric shell ratio should be optimized so as not to exceed a specific limit, for our case two thirds of the grain volume, to secure temperature stability of the dielectric properties of BaTiO3.

Keywords:

barium titanate, core/shell structure, dielectric properties, temperature stability
Received: 14 January 2014 Accepted: 27 January 2014 Published: 05 March 2014 Issue date: March 2014
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Publication history

Received: 14 January 2014
Accepted: 27 January 2014
Published: 05 March 2014
Issue date: March 2014

Copyright

© The author(s) 2014

Acknowledgements

This work was supported by the Samsung Electro- Mechanics Co. Ltd. through the Center for Advanced MLCC-Manufacturing Processes and also by the Priority Research Centers Program (Grant No. 2012- 048034) through the National Research Foundation of Korea (NRF) funded by the Ministry of Education, Science and Technology (MEST), Korea.

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