The electronic properties of the Ba/SiC/Si(111)-8° nanointerface have been studied for the first time by photoelectron spectroscopy using synchrotron radiation. The experiments are conducted in situ in superhigh vacuum on submonolayer Ba coatings of SiC/Si(111)-8° samples grown by the method of substitution of atoms. It is found that the adsorption of Ba causes strong changes in the spectrum of the C 1 s core level. It is shown that the effect is due to the formation of a new, previously unknown carbon nanostructure. It is found that the nanostructure is formed exclusively on the SiC vicinal surfaces in the presence of stabilizing adsorbed Ba metal atoms and consists of carbon rings, in which the chemical bonds are close in nature to the bonds characteristic of aromatic compounds.

We carried out a structural-spectroscopic study of AlGaN/GaN epitaxial layers grown by molecular-beam epitaxy with nitrogen plasma activation on a hybrid substrate containing layers of silicon carbide and porous silicon. Using X-ray diffractometry, Raman and photoluminescence spectroscopy, it is shown that thin films formed on a hybrid substrate have minimal residual stresses and intense photoluminescence.