Microstructure of relaxed InN quantum dots grown on GaN buffer layers by molecular-beam epitaxy
- 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, Journal Name: Applied Physics Letters Journal Issue: 23 Vol. 88; ISSN APPLAB; ISSN 0003-6951
- Country of Publication:
- United States
- Language:
- English
Similar Records
Growth and characterizations of semipolar (1122) InN
Microstructure of GaN epitaxy on SiC using AlN buffer layers