Bratus O. Electrophysical and structural properties of layered systems with silicon nanoinclusions.

The comprehensive studies of structural properties of the nanocomposite SiO2(Si) films obtained by ion-plasma sputtering (IPS) and plasma enhanced chemical vapor deposition (PE CVD) methods are presented. The main basic laws of silicon enriched SiOx films transformation into nanocomposite SiO2(Si) films containing Si nanocrystals in dielectric matrix after high temperature annealing have been investigated by various methods. Comparison of PL spectra of the films obtained by IPS and PE CVD methods shows the presence of a wide spectrum band in PL spectra of initial SiOx films, but after high temperature annealing the nanocomposite films obtained by PE CVD method show a narrow intensive peak of the PL in the range 1.46 - 1.57 eV. The mechanism of electrical conductivity of nanocomposite SiO2(Si) films obtained by IPS method with subsequent high temperature annealing has been revealed. Electrical conductivity of films corresponds to the mechanism of hopping conductivity with variable hopping length due to a large number of silicon dangling bonds in the dielectric matrix. The effect of negative differential capacitance of MIS structures with nanocomposite SiO2(Si) films as the dielectric has been revealed and the physical model for its explanation has been proposed.