Schwoebel barriers andquantum dot lateral size equalization during epitaxial growth

Abstract

Self-assembled 3D island formation during epitaxial growth wasinvestigated using kinetic Monte Carlo models. Schwoebelbarriers for the explanation of 3D kinetic growth were suggested.The diffusion hop probability ratio χ for atom hops up to atomhops down, leading to 2D, 3D and Stranski-Krastanov growth modes, was obtained. The necessity of atomic flux from the island edgeto the upper layers for 3D island formation was demonstrated.Island size equalization during the growth process was observed forcertain χ values. The reason for the equalization of separate3D island lateral sizes is the increase in atomic flux to theupper layer. The new layer nucleus on the top of the island becomes the trap for atoms detached from the edges of the lowerlayer.