The evolution of self-assembled InAs/GaAs(001) quantum dots grown by growth-interrupted molecular beam epitaxy.
Self-assembled InAs quantum dots (QDs) grown on GaAs(001) by molecular beam epitaxy under continuous and growth-interruption modes exhibit two families of QDs, quasi-three-dimensional (quasi-3D; Q3D) and three-dimensional (3D) QDs, whose volume density evolution is quantitatively described by a classical rate-equation kinetic model. The volume density of small Q3D QDs decreases exponentially with time during the interruption, while the single-dot mean volume of the large QDs increases by Ostwald ripening. The kinetics of growth involves the conversion of Q3D to 3D QDs at a rate determined by the superstress and the participation of the wetting layer adatoms. The data analysis excludes Q3D QDs being extrinsic surface features due to inefficient cooling after growth.
Balzarotti
Adalberto
A
Dipartimento di Fisica, Università di Roma 'Tor Vergata', Via della Ricerca Scientifica, I-00133 Roma, Italy.