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 = 1/3〈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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Acknowledgments
This work was supported in part by the Grant-in-Aid for Scientific Research on Priority Areas “Nano Materials Science for Atomic-Scale Modification” (No. 19053001) from the Ministry of Education, Culture, Sports and Technology (MEXT) of Japan. Y.T. is supported as a Japan Society for the Promotion of Science (JSPS) research fellow. N.S. acknowledges support from PRESTO, Japan Science and Technology Agency.
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Tokumoto, Y., Shibata, N., Mizoguchi, T. et al. High-resolution transmission electron microscopy (HRTEM) observation of dislocation structures in AlN thin films. Journal of Materials Research 23, 2188–2194 (2008). https://doi.org/10.1557/JMR.2008.0265
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DOI: https://doi.org/10.1557/JMR.2008.0265