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.

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The structure of nonstoichiometric silicon oxide (SiO_ x ) has been studied by the methods of highresolution X-ray photoelectron spectroscopy and fundamental optical-absorption spectroscopy. The conductivity of SiO_ x ( x = 1.4 and 1.6) films has been measured in a wide range of electric fields and temperatures. Experimental data are described in terms of the proposed SiO_ x structure model based on the concept of fluctuating chemical composition leading to nanoscale fluctuations in the electric potential. The maximum amplitude of potential fluctuations amounts to 2.6 eV for electrons and 3.8 eV for holes. In the framework of this model, the observed conductivity of SiO_ x is described by the Shklovskii–Efros theory of percolation in inhomogeneous media. The characteristic spatial scale of potential fluctuations in SiO_ x films is about 3 nm. The electron-percolation energy in SiO_1.4 and SiO_1.6 films is estimated to be 0.5 and 0.8 eV, respectively.

Экспериментально измерена релаксация тока в структуре металл−нитрид−оксид−полупроводник. Эксперимент сравнивается с расчетом, основанным на двухзонной модели проводимости и многофононном механизме ионизации ловушек. Из сравнения эксперимента с расчетом для величины сечения рекомбинации получена оценка сверху, которая составила 5 • 10 −13 cm 2 .