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arXiv · 1208.1568

Nonstoichiometric doping and Bi antisite defect in single crystal Bi2Se3

F. -T. Huang·M. -W. Chu·H. H. Kung·W. L. Lee·R. Sankar·S. -C. Liou·K. K. Wu·Y. K. Kuo·F. C. Chou
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Abstract

We studied the defects of Bi2Se3 generated from Bridgman growth of stoichiometric and nonstoichiometric self-fluxes. Growth habit, lattice size, and transport properties are strongly affected by the types of defect generated. Major defect types of Bi_Se antisite and partial Bi_2-layer intercalation are identified through combined studies of direct atomic-scale imaging with scanning transmission electron microscopy (STEM) in conjunction with energy-dispersive X-ray spectroscopy (STEM-EDX), X-ray diffraction, and Hall effect measurements. We propose a consistent explanation to the origin of defect type, growth morphology, and transport property.

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F. -T. Huang, M. -W. Chu, H. H. Kung, W. L. Lee, R. Sankar, S. -C. Liou, K. K. Wu, Y. K. Kuo, F. C. Chou. 2012-08-08. Nonstoichiometric doping and Bi antisite defect in single crystal Bi2Se3. https://doi.org/10.1103/physrevb.86.081104

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