Anisotropic Misfit Strain Relaxation in Thin Epitaxial Layers
نویسنده
چکیده
The structure of AlGaAs, MnMgTe/CdTe and CdTe epitaxial layers deposited on GaAs substrates was studied by high-resolution X-ray diffractometry. The reciprocal lattice mapping and the rocking curve techniques were used for the samples aligned with either [110] or [ 110] direction perpendicular to the diffraction plane. Our results show that strains in the investigated samples were anisotropic. This means that unit cells of layers were not tetragonal but possessed a lower symmetry. Our findings can be explained by anisotropic relaxation of strain caused by a higher mobility of the [ 110]-oriented dislocations than that oriented in the [110] direction.
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