In this work, we have investigated the photocurrent and spectral sensitivity of the silicon/SrTiO₃:xNb/perovskite structures. The sol–gel method carried out the deposition of undoped SrTiO₃ layers as well as niobium-doped (SrTiO₃:Nb) layers at atomic concentrations of 3 and 6% Nb. The perovskite layer, CH₃NH₃PbI_3−xCl_x, has been deposited by the vacuum co-evaporation technique. The layers have been characterized by scanning electron microscopy and X-ray diffraction measurements. The volt–ampere characteristics and spectral sensitivity of the fabricated samples have been measured under illumination with selective wavelengths of 405, 450, 520, 660, 780, 808, 905, 980, and 1064 nm of laser diodes. We have shown that for different configurations of applied voltage between silicon, SrTiO₃:xNb, and CH₃NH₃PbI_3−xCl_x, the structures are photosensitive ones with a variation of photocurrent from microamperes to milliamperes depending on Nb concentration in SrTiO₃, and the highest photocurrent and spectral sensitivity values are observed when a SrTiO₃:Nb layer with 3 at.% of Nb is used. A possible application of the proposed structure with a SrTiO₃:Nb layer for perovskite solar cells and photodetectors is being discussed.

The electrical characteristics of metal-oxide-semiconductor (MOS) structures with silicon nanoparticles embedded in silicon oxide have been studied. The nanocrystals are formed by decomposition of an oversaturated solid solution of implanted silicon during thermal annealing at a temperature of ∼1000°C. At liquid-nitrogen temperature, a stepped current-voltage characteristic is observed in a MOS structure consisting of Si nanocrystals in a SiO₂ film. The stepped current-voltage characteristic is, for the first time, quantitatively described using a model in which charge transport occurs via a chain of local states containing a silicon nanocrystal. The presence of steps is found to be associated with one-electron charging of the silicon nanocrystal and Coulomb blockade of the probability of a hop from the nearest local state to the conducting chain. The local states in silicon dioxide are assumed to be related to an excess of silicon atoms. The presence of such states is confirmed by measurements of the differential conductance and capacitance. For MOS structures implanted with silicon, the differential capacitance and conductance are found to be higher, compared to the reference structures, in the range of biases exceeding 0.2 V. In the same bias range, the conductance is observed to decrease under ultraviolet irradiation due to a change in the population of the states in the conductivity chains.