Reversibility of the island shape, volume and density in Stranski-Krastanow growth

We report on reversible and irreversible phenomena in size-limited InAs island growth (SLIG) on GaAs(001) surface. We found that, with increasing the substrate temperature, the island density of the SLIG islands decreases, the lateral size of the islands increases and the islands strongly flatten. The average volume is either decreased or weakly affected. The total amount of InAs accumulated in quantum dots (QDs) strongly decreases in favour of the gas of In adatoms on the surface. Both unidirectional and reversible tuning of the substrate temperature after formation of the islands causes reversible changes in the island shape and density. We show the possibility of dramatically increasing the volume and the density of QDs approaching the strategically important 1.3 µm wavelength range via adatom condensation with cooling of the substrate after the formation of QDs. We also demonstrate that the substrate temperature cycling procedure may remarkably reduce the defect density in QD structures.