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Non-stoichiometric silicon nitride SiNx, enriched with silicon, is a promising material for the non-volatile resistive memory development. The current studies devoted to investigation of the optical properties of SiNx synthesized in a low-pressure reactor at 800 oC at different ratios of dichlorosilane (SiH2Cl2) to ammonia (NH3). It was found that for films synthesized at SiH2Cl2/NH3 ratio =1/1, 1/2 and 1/3, the corresponding bandgap values are 3.83, 4.17 and 4.40 eV. At the same time, the corresponding values of the parameter x, found according to the theoretical dependence of the bandgap value on x for SiNx calculated from the first principles, are 1.26, 1.30 and 1.32. Thus, by increasing the SiH2Cl2/NH3 ratio, it is possible to create non-stoichiometric SiNx films with a controlled silicon enrichment degree with high uniformity of chemical composition and thickness.

The atomic structure and electron spectrum of a-SiOx:H films deposited on silicon and glass substrates by the plasma enhanced chemical vapor deposition method are considered in this paper. The film stoichiometric parameter «x» varied in the range from 0.57 to 2 depending on the oxygen supply to the reactor conditions. The film structures and the electronic structure peculiarities characterization, depending on the parameter «x» value, were carried out using a set of structural and optical techniques, as well as the ab initio quantum-chemical simulation for the model SiOx structure. It was established that the studied SiOx:H films mainly consist of silicon suboxide SiOy with SiO2 and amorphous Si clusters. Based on the spatial chemical composition fluctuations, the electron and hole potential fluctuations model for SiOx is proposed. The obtained results will allow a more accurate charge transport modeling in a-SiOx:H films, which is important for creating nonvolatile memory and memristor elements on the base of SiOx.

The electronic structure of vacancy-type defects in hexagonal boron nitride (h-BN) synthesized by chemical vapor deposition, promising for microelectronics, is studied. The research is carried out using X-ray photoelectron spectroscopy and a simulation within the density functional theory. It is shown that the h-BN bombardment with argon ions leads not only to the near-surface layer cleaning from organic pollutants, but also to the generation of a high intrinsic defects concentration, mainly boron-nitrogen divacances. The greater the boron-nitrogen divacances concentration is, the longer the bombardment time is. The boron-nitrogen divacansion in h-BN is a significantly more energetically favorable defect than that of isolated boron and nitrogen vacancies. It is concluded that the most probable diamagnetic vacancy-type defects capable of participating in localization and, as a consequence, in charge transport in h-BN films is the boron-nitrogen divacancy.