Strain relaxation and segregation effects during self-assembled InAs quantum dots formation on GaAs(001)

Abstract

In segregation effects during InAs growth on GaAs(001) and critical thickness for InAs self-assembled quantum dots are studied using a real time, in situ technique capable of measuring accumulated stress during growth. Due to a large (~50%) surface In segregation of floating In, self-assembled dot formation takes place when less than one monolayer of InAs is pseudomorphically grown on GaAs. A picture of the growth process is discussed on the basis of the equilibrium between InAs and floating In dominated by the stress energy.