Anisotropic strain relaxation and surface morphology related to asymmetry in the formation of misfit dislocations in InGaAs/GaAs heterostructures
نویسندگان
چکیده
Partially relaxed InGaAs/GaAs heterostructures with a small lattice mismatch (less than 1%), grown by metalorganic vapour-phase epitaxy have been studied by the transmission electron microscopy, atomic force microscopy as well as X-ray diffractometry. A regular network of 60° misfit dislocations formed at the (001) interface in two orthogonal 〈110〉 crystallographic directions has been revealed. A close correspondence between distribution of the interfacial misfit dislocations and undulating surface morphology in the form of a characteristic cross-hatch pattern has been observed. The structural analysis applied for the samples oriented either in [110] or [110] perpendicular directions, using reciprocal lattice mapping, revealed anisotropic strain relaxation, related to the asymmetry in the formation of α and β misfit dislocations along these both directions, respectively.
منابع مشابه
Formation of misfit dislocations in strained-layer GaAs/In
The Open University's repository of research publications and other research outputs Formation of misfit dislocations in strained-layer GaAs/In x Ga 1–x As/GaAs heterostructures during postfabrication thermal processing Journal Article (2003). Formation of misfit dislocations in strained-layer GaAs/InxGa1–xAs/GaAs heterostructures during postfabrication thermal processing. It is demonstrated th...
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