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High-resolution transmission electron microscopy (HRTEM) observation of dislocation structures in AlN thin films

Published online by Cambridge University Press:  31 January 2011

Yuki Tokumoto
Affiliation:
Department of Advanced Materials Science, Graduate School of Frontier Science, The University of Tokyo, Kashiwa, Chiba 277-8651, Japan
Naoya Shibata
Affiliation:
Institute of Engineering Innovation, School of Engineering, The University of Tokyo, Bunkyo, Tokyo 113-8656, Japan; and PRESTO, JST, Kawaguchi, Saitama 332-0012, Japan
Teruyasu Mizoguchi
Affiliation:
Institute of Engineering Innovation, School of Engineering, The University of Tokyo, Bunkyo, Tokyo 113-8656, Japan
Masakazu Sugiyama
Affiliation:
Institute of Engineering Innovation, School of Engineering, The University of Tokyo, Bunkyo, Tokyo 113-8656, Japan
Yukihiro Shimogaki
Affiliation:
Department of Materials Engineering, School of Engineering, The University of Tokyo, Bunkyo, Tokyo 113-8656, Japan
Jung-Seung Yang
Affiliation:
Department of Materials Engineering, School of Engineering, The University of Tokyo, Bunkyo, Tokyo 113-8656, Japan
Takahisa Yamamoto
Affiliation:
Department of Advanced Materials Science, Graduate School of Frontier Science, The University of Tokyo, Kashiwa, Chiba 277-8651, Japan
Yuichi Ikuhara*
Affiliation:
Institute of Engineering Innovation, School of Engineering, The University of Tokyo, Bunkyo, Tokyo 113-8656, Japan; and WPI Advanced Institute for Materials Research, Tohoku University, Sendai 980-8577, Japan
*
a)Address all correspondence to this author. e-mail: [email protected]
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Abstract

The structure and configuration of threading dislocations (TDs) in AlN films grown on (0001) sapphire by metal–organic vapor phase epitaxy (MOVPE) were characterized by high-resolution transmission electron microscopy (HRTEM). It was found that the TDs formed in the films were mainly the perfect edge dislocations with the Burgers vector of b = ⅓〈11¯20〉. The majority of the edge TDs were not randomly formed but densely arranged in lines. The arrays of the edge TDs were mainly observed on the {11¯20} and {10¯10} planes. These two planes showed different configurations of TDs. TD arrays on both of these planes constituted low-angle boundaries. We suggest that these TDs are introduced to compensate for slight misorientations between the subgrains during the film growth.

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Articles
Copyright
Copyright © Materials Research Society 2008

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References

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