The monitoring of 2d-3d transition for InAs/GaAs (001) self-assembled quantum dots by atomic force microscopy

We present a detailed Atomic Force Microscopy study of InAs/GaAs (001) selfassembled quantum dots grown by Molecular Beam Epitaxy during its complete evolution cycle (transition from 2D islands to 3D islands). We have performed a statistical analysis regarding quantum dot number density distributions (for quasi-3D value of quasi-3D QDs decreases from 1.1 x 10 cm to 4.3 x 10 cm for a coverage between 1.57 ML and 1.61 ML, while for 3D QDs it increases by a factor of 10 (from 2.1 x 1010 cm-2 to 2.3 x 1010 cm-2) so as the 3D QDs become the prevailed structures. We can assume as critical coverage, 1.59 ML.