Strain status of self-assembled InAs quantum dots

Grazing incidence x-ray diffraction experiments employing the asymmetric (2 02) Bragg diffraction have been performed to characterize self-assembled In As quantum dots grown by molecular-beam epitaxy. We find that the strain is elastically relaxed with different components. The volume distribution of partially strained InAs inside islands is peaked at intermediate strain val ues. The fraction of both almost fully strained and totally relaxed InAs is found to be small. In addition, a small volume fraction of relaxed InxGa1- xAs is found. (C) 2000 American Institute of Physics. [S0003- 6951(00)02335 -4].