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DOE OSTI · 22486245

Dislocation core structures in Si-doped GaN

Fu, W. Y.·Sahonta, S. -L.·Kappers, M. J.·Humphreys, C. J.·Horton, M. K.·Pennycook, T. J.·Dusane, R. O.·Moram, M. A.
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Abstract

Aberration-corrected scanning transmission electron microscopy was used to investigate the core structures of threading dislocations in plan-view geometry of GaN films with a range of Si-doping levels and dislocation densities ranging between (5 ± 1) × 10{sup 8} and (10 ± 1) × 10{sup 9} cm{sup −2}. All a-type (edge) dislocation core structures in all samples formed 5/7-atom ring core structures, whereas all (a + c)-type (mixed) dislocations formed either double 5/6-atom, dissociated 7/4/8/4/9-atom, or dissociated 7/4/8/4/8/4/9-atom core structures. This shows that Si-doping does not affect threading dislocation core structures in GaN. However, electron beam damage at 300 keV produces 4-atom ring structures for (a + c)-type cores in Si-doped GaN.

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71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICSATOMSDAMAGEDENSITYDOPED MATERIALSEDGE DISLOCATIONSELECTRON BEAMSFILMSGALLIUM NITRIDESGEOMETRYKEV RANGE 100-1000TRANSMISSION ELECTRON MICROSCOPY

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Fu, W. Y., Sahonta, S. -L., Kappers, M. J., Humphreys, C. J., Horton, M. K., Pennycook, T. J., Dusane, R. O., Moram, M. A.. 2015-12-14. Dislocation core structures in Si-doped GaN. https://doi.org/10.1063/1.4937457

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