About this Abstract |
Meeting |
MS&T22: Materials Science & Technology
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Symposium
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Grain Boundaries, Interfaces, and Surfaces: Fundamental Structure-Property-Performance Relationships
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Presentation Title |
Atomic Structure Analysis of Inversion Domain Boundary in MgO-doped AlN |
Author(s) |
Daiki Kato, Bin Feng, Yasunobu Noritake, Tomoko Hishida, Naoya Shibata, Yuichi Ikuhara |
On-Site Speaker (Planned) |
Daiki Kato |
Abstract Scope |
Aluminum nitride (AlN) has been widely used as an insulating and heat-dissipating substrate material because of its various properties, such as high thermal conductivity, high insulation, and high strength. The volume resistivity of MgO-doped AlN was found to increase by about 4 orders of magnitude compared to pristine AlN. However, the detailed mechanism of this increase is still unknown. In this study, in order to understand the structural origin of the enhanced volume resistivity, the microstructure and local composition of MgO-doped AlN were analyzed in detail using state of the art scanning transmission electron microscopy (STEM). It was found that Mg and O segregate into intragranular defects inside AlN grains. Atomic resolution observations confirmed that the defects were Inversion Domain Boundaries (IDBs), which invert the polarity of the bulk. The IDBs were found to have a similar structure to the MgO octahedron, with Mg and O segregated in these layers. |