The transition from thermodynamically to kinetically controlled formation of quantum dots in an InAs/GaAs(100) system

The results of experimental and theoretical studies of quantum dot formation in an InAs/GaAs(100) system in the case of a subcritical width of the deposited InAs layer (1.5–1.6 monolayers) are presented. It is shown that, in the subcritical range of InAs thicknesses (smaller than 1.6 monolayers), regardless of the deposition rate, the density of quantum dots increases and their size decreases in response to an increase in surface temperature. In the overcritical range of InAs thicknesses (more than 1.8 monolayers), the density of quantum dots increases and their size decreases in response to a decrease in temperature and an increase in the deposition rate. The observed behavior of quantum dot morphology is attributed to the transition from a thermodynamically to kinetically controlled regime of quantum dot formation near the critical thickness.