Self-assembled InAs quantum dots grown on InP (3 1 1)B substrates: Role of buffer layer and amount of InAs deposited

The formation of InAs quantum dots by Stransky-Krastanow method on (311)B InP substrates has been studied. On Al0.48In0.52As alloy lattice matched on InP, large changes of the quantum dot structural characteristics were observed as a function of the amount of InAs deposited and of the As pressure during the InAs quantum dots formation. Small quantum dots (minimum diameter = 20 nm) in very high density ( 1.3 x10 quantum dots per cm) were achieved in optimized growth conditions. These results are interpreted from the strong strain field interaction though the substrate at high density and from the InAs surface energy evolutions with the As pressure. The effect on quantum dot characteristics of the arsenic pressure during the growth of Al0.48In0.52As buffer layers has been also investigated. Despite the importance of this parameter on the Al0.48In0.52As clustering, weak changes on quantum dots were observed.