Microstructure of relaxed InN quantum dots grown on GaN buffer layers by molecular-beam epitaxy

Journal Article · Mon Jun 05 00:00:00 EDT 2006 · Applied Physics Letters

DOI:https://doi.org/10.1063/1.2205166· OSTI ID:20779384

Lin, Zhou; Tao, Xu; Smith, David J; Moustakas, T D ^[1]

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1. Center for Solid State Science, Arizona State University, Tempe, Arizona 85287 (United States) and Department of Physics and Astronomy, Arizona State University, Tempe, Arizona 85287 (United States)

Electron microscopy has been used to characterize the microstructure of InN quantum dots (QDs) grown by molecular-beam epitaxy on GaN(0001)/AlN(0001)/sapphire substrates at 425 deg. C under slightly group III-rich conditions. Observations in plan-view and cross-section geometries established that the large majority of the InN QDs were invariably associated with threading dislocations in the underlying GaN buffer layer having edge components. Periodic, primarily hexagonal, arrays of misfit dislocations separated by {approx}2.8 nm were observed at the InN QD/GaN interface, indicating that the QDs were almost completely relaxed. No evidence for an InN wetting layer was obtained either in situ by reflection high-energy electron diffraction or ex situ by transmission electron microscopy.

• OSTI ID: 20779384
• Journal Information: Applied Physics Letters, Vol. 88, Issue 23; Other Information: DOI: 10.1063/1.2205166; (c) 2006 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); ISSN 0003-6951
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ALUMINIUM NITRIDES
CROSS SECTIONS
CRYSTAL GROWTH
DISLOCATIONS
ELECTRON DIFFRACTION
GALLIUM NITRIDES
INDIUM NITRIDES
LAYERS
MICROSTRUCTURE
MOLECULAR BEAM EPITAXY
PERIODICITY
QUANTUM DOTS
SAPPHIRE
SEMICONDUCTOR MATERIALS
SUBSTRATES
TRANSMISSION ELECTRON MICROSCOPY