Study of InAs/GaAs quantum dots formation in subcritical growth modes on patterned substrates

In this work we present the results of experimental studies of the InAs/GaAs quantum dot formation in subcritical growth modes on nanopatterned substrates. For this purpose, we used two ways for surface patterning: local droplet etching and modified oxide desorption technique. We have experimentally shown that both methods allow in situ formation of nanosized pits (or nanoholes) on the surface, but their shape and density is quite different. We also have shown that the using of growing surface nanopatterning allows both to obtain self-assembled nanostructures (including QD) at subcritical deposition thicknesses and to localize its formation in nanoholes with high selectivity and suppressing a wetting layer formation. In addition, our results have also shown that the nanohole character on a structured surface (shape, size, density) has a key effect on both the processes of nanostructure nucleation and growth and their structural and optical properties, which should also be taken into account when developing methods for creating heterostructures with regular arrays of quantum dots.