Comparative study of low temperature growth of InAs and InMnAs quantum dots

The evolution of InAs and In0.85Mn0.15As quantum dots grown at 270 °C is studied as a function of coverage. We show that, in contrast to what occurs at high temperature, the two-dimensional to three-dimensional transition is not abrupt but rather slow. This is due to the finding that part of the deposited material also contributes to the wetting layer growth after quantum dot formation. This aspect is particularly accentuated in In0.85Mn0.15As deposition. The Voronoi area analysis reveals a significant spatial correlation between islands.