Atomic structure of Ge quantum dots on the Si(001) surface
L. V. Arapkina, V. A. Yuryev
A. M. Prokhorov General Physics Institute RAS, 119991 Moscow, Russia
Abstract
In situ morphological investigation of the 105 faceted Ge
islands on the Si(001) surface (hut clusters) have been carried out using an
ultra high vacuum instrument integrating a high resolution scanning
tunnelling microscope and a molecular beam epitaxy vessel. Both species of
hut clusters-pyramids and wedges-were found to have the same structure of
the 105 facets which was visualized. Structures of vertexes of the
pyramidal clusters and ridges of the wedge-shaped clusters were revealed as
well and found to be different. This allowed us to propose a crystallographic
model of the 105 facets as well as models of the atomic structure of both
species of the hut clusters. An inference is made that transitions between
the cluster shapes are impossible.