ABSTRACT

The progress on the research of self-organized growth and microstructure characterization of Ge quantum dots on Si substrates is reviewed in this paper. By using the combination of grazing incidence and conventional x-ray diffractions as well as the transmission electron microscopy along with the energy filtered imaging technique, both strain and composition of Ge dots could be obtained simultaneously. Besides the three-dimensional islanding growth and the formation of misfit dislocations at the interface, alloying is another way to release the misfit strain especially at high growth temperatures. The strain  relaxation is a driving force for the formation of Ge quantum dots on Si substrates. Accordingly, the size, density and size uniformity of Ge quantum dots could be tailored at a certain degree not only by controlling the growth parameters but also by introducing the surfactant and the multilayer structure. While the lateral ordering of quantum dots could be realized by using the patterned or vicinal Si surfaces.