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Results of experimental studies presenting data on the effect of electron trapping centers on the properties of Pb_1−xSn_xTe : In with x ≈ 0.24-0.29 at temperatures below 20 K are described. A model is developed that consistently explains a number of phenomena in Pb_1−xSn_xTe : In solid solutions, including current-voltage characteristics in the absence of light resulting from the injection from contacts and space-charge limited current when electrons are captured in traps distributed in energy in the bandgap, photoelectric phenomena in the infrared and terahertz spectral ranges, features of galvanomagnetic phenomena, and fluctuations and autooscillations of current in the absence or presence of light.

The interaction of the GaSb(001) surface with fluxes of As₂, As₄, and Sb₄ molecules is studied using reflection high-energy electron diffraction. It is shown that As₂ molecules interact with a GaSb surface predominantly by an exchange mechanism, and As₄ molecules by the vacancy mechanism. It is established that for the reproducible generation of In-Sb heterointerfaces in InAs/GaSb superlattices, one needs to use a flux of As₄ molecules rather than As₂ molecules.

The plasma oxidation of a silicon surface in an inductive plasma generation reactor were studied using spectroscopic ellipsometry and atomic emission spectroscopy. The effect of inert gases on the formation kinetics of ultrathin SiO2 films is discussed. The effect of intense oxidation of Si in the plasma formed by nominally pure helium was found. It is suggested that this effect is due to the photostimulated acceleration of the reaction at the silicon-oxide interface by the intrinsic optical emission from the helium plasma.

A possibility of using a new method of film synthesis in a supersonic flow of a hydrocarbon plasma generated by a disk-type magnetohydrodynamic accelerator is demonstrated. Two methods are used for characterization of diamond-like carbon films: nondestructive spectroscopic ellipsometry and atomic-force microscopy.

The surface of biochips prepared on the basis of silicon wafers for studies of reactions of pre-immobilized oligonucleotides and protein molecules was analyzed by high-resolution scanning ellipsometry. The hybridization interactions of nucleic acid (duplex formation in the reaction of an amplicon of the influenza A virus matrix protein gene with probe molecules), sorption of protein molecules, and protein-protein interactions on the surface of the biochip were detected. It was shown that pre-sorption of gold nanoparticles led to greater efficiency of immobilization of protein molecules on the biochip. The experimental data suggest that that ellipsometry is a highly sensitive, nondestructive and inexpensive label-free method for the detection of the biochip surface, which is suitable for quantitative analysis of reactions of biomolecules.

The ultimate efficiency of a three-pin solar cell based on the GaAs/Si structure is calculated by means of numerical simulation in a diffusion-drift approximation. Dependences of the efficiency on the GaAs layer thickness and the density of dislocations threading in this layer, which are known to affect the lifetime of nonequilibrium charge carriers. It is shown that the maximum limit efficiency (27 %) of such a structure is reached at the GaAs layer thickness of about 1.4 µm and the density ofthreading dislocations of less than 106 cm⁻².

Optical properties of Ga- and N-polar triple nitrides Al_xGa_1−xN with molar fractions of aluminum from 0 to 0.6 are studied by a nondestructive contactless method of spectroscopic ellipsometry. Correlation dependences of the shift of the fundamental absorption edge and the behavior of the real and imaginary parts of the pseudodielectric function on the composition x and polarity of the Al_xGa_1−xN layers are revealed. It is verified that the polarity of the layers grown by molecular beam epitaxy is defined by the formation of the AlN nucleating layer.

The mechanism of formation of silicon nanoclusters in layers of nonstoichiometric composition is studied by Monte Carlo simulation. Interest in silicon nanoclusters (Si-nc) coated with an oxide layer is due to their applications in modern optoelectronics and nanoelectronics. A lattice Monte Carlo model is proposed to study atomic processes in the Si-SiO₂ system. The formation of silicon nanoclusters during annealing of single SiO layers and SiO₂-SiO-SiO₂ layered structures is studied. Along with the diffusive motion of particles, the model takes into account the formation and collapse of mobile molecules of silicon monoxide. It is shown that accounting for transport of silicon under high-temperature annealing due to the motion of SiO accelerates the formation of Si-nc. Dependences of the size of nanoclusters on temperature, annealing time, and the composition of the SiO_x layer are obtained. It is found that annealing of silica films containing layers of nonstoichiometric composition can lead to the formation of silicon nanoclusters or cavities.

Technical parameters and possible applications of an infrared scanning microscope with a spatial resolution of up to 3 µm are considered. It is shown that the device works with both array and linear photodetectors. Original PC software was designed to control the scanning process interactively and receive and process images of objects in the infrared range,.

Operation of a photodetector in an infrared microscope has a number of features preventing the application of calibration methods known for thermal imaging devices. A differential method of calibration is proposed which gives an opportunity to consider the nonlinearity of the transfer characteristics of the photodetector reading unit and electronic path and the variation of the background radiation flux.