Morphology, Structure, and Optical Properties of Semiconductor Films with GeSiSn Nanoislands and Strained Layers.

The dependences of the two-dimensional to three-dimensional growth (2D-3D) critical transition thickness on the composition for GeSiSn films with a fixed Ge content and Sn content from 0 to 16% at the growth temperature of 150 °С have been obtained. The phase diagrams of the superstructure change during the epitaxial growth of Sn on Si and on Ge(100) have been built. Using the phase diagram data, it becomes possible to identify the Sn cover on the Si surface and to control the Sn segregation on the superstructure observed on the reflection high-energy electron diffraction (RHEED) pattern.

Ge quantum dots structural peculiarities depending on the preparation conditions.

Two-dimensional pseudomorphous Ge films have been grown to a critical thickness of 4 monolayers (ML) on Si(001). As a result of continuing deposition, pyramid-like Ge islands were grown in Stranski-Krastanov mode. The pyramid-like Ge islands deposited on Si(001) substrate using molecular beam epitaxy at 573 K reveal quantum dots (QDs) properties.