Peculiarities of growth of InAs quantum dot arrays with low surface density by molecular beam epitaxy

The influence of the substrate temperature and the flux of In adatoms on the structural and optical characteristics of InAs quantum dots with a low surface density is experimentally studied. An increase in the substrate temperature under conditions of a high flux of In adatoms promotes an increase in their surface migration and a certain decrease in the density of the array of quantum dots (down to $\sim$ (1–2) $\cdot$ 10$^{10}$ cm$^{-2}$), however, in this case a significant short-wavelength shift of the photoluminescence spectrum is observed despite an increase in lateral sizes of dots. A decrease in the incident flux of In adatoms at optimal substrate temperatures makes it possible to reduce the dot density more efficiently (down to $\sim$ (1–2) $\cdot$ 10$^9$ cm$^{-2}$).