A. V. Rzhanov Institute of Semiconductor Physics Siberian branch of the RAS

P. A. Kuchinskaya, V. A. Zinovyev, V. A. Armbrister

A. V. Rzhanov Institute of Semiconductor Physics Siberian branch of the RAS, Novosibirsk state university

A. V. Nenashev,  V. A. Volodin, A. V. Dvurechenskii

In this paper, we study formation of SiGe nanometer−sized rings on Si(100) during molecular beam epitaxy. The detailed morphology and size distribution of these structures were investigated by atomic force microscopy. Element composition of nanorings was studied by Raman spectroscopy. It was found, that average Ge content of the rings grown at temperature 680 °C is 37 %. The energy spectrum and charge density distribution which correspond to hole states localized in the SiGe quantum rings were calculated by 6−band k×p method. Experimental data about geometry and composition of the nanorings were used. The results of these calculations demonstrated, that heterostructures with SiGe quantum rings are perspective for device application in the range of terahertz and infra red radiation detection.

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