Elastic fields in a system consisting of a surface coherent axisymmetric quantum dot-island on a massive substrate have been theoretically studied using the finite element method. An analysis of the influence of the quantum dot shape (form factor) and relative size (aspect ratio) δ on the accompanying elastic fields has revealed two critical quantum dot dimensions, δ_(c1) and δ_(c2). For δ & δ_(c1), the fields are independent of the quantum dot shape and aspect ratio. At δ ≥ δ_(c2), the quantum dot top remains almost undistorted. Variation of the stress tensor component σ_(zz) (z is the quantum dot axis of symmetry) reveals a region of tensile stresses, which is located in the substrate under the quantum dot at a particular distance from the interface. Using an approximate analytical formula for the radial component of displacements, model electron microscopy images have been calculated for quantum dot islands with δ & δ_(c1) in the InSb/InAs system. The possibility of stress relaxation occurring in the system via the formation of a prismatic interstitial dislocation loop has been considered.
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