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The article is devoted to the problem of professional selection of personnel in private security organizations. This problem is relevant, since a significant (and even excessive) number of employees are engaged in security activities in the Russian economy, and their professionalism is a subject of discussion both among managers and personnel officers, and among ordinary people. The article briefly examines the system of professional selection and substantiates the stages of the research carried out by the author in accordance with the order of one of the security fiLms management, which provides physical protection of sensitive facilities. The article briefly examines the system of professional selection and substantiates the stages of the research carried out by the author in accordance with the order of the management of one of the security firms, which provides physical protection of sensitive facilities. An expert-stating method of constructing a psychogram is described. It provides for: expert assessment of personnel to determine successful and unsuccessful employees; selection of methods and techniques of psychodiagnostics and testing of successful and unsuccessful employees; identification of statistically significant differences in test results between successful and unsuccessful employees and determination of professionally important qualities. Difficulties and limitations in the implementation of these research procedures are analyzed in detail. As a result of the study, a psychological portrait of a successful security guard is presented, carrying out physical protection of sensitive objects. This portrait includes a general description of the factors of success, as well as a description of specific professionally important qualities.

The properties of interfaces in the heterostructures which frequently govern their operation are of particular importance for the devices containing heterostructures as active elements. Any further improving of the characteristics of semiconductor devices is impossible without a detail analysis of the processes occurring at the interfaces of heterojunctions. At the same time, the results largely depend on the purity of the starting materials and the technology of layer manufacturing. Moreover, the requirements to the composition and distribution of the impurity steadily get stringent. Therefore, the requirements regarding the methods of the impurity control and carrier distribution also become tougher both in the stage of laboratory development of the structure and in various stages of manufacturing of semiconductor devices. Electrochemical capacitance-voltage profiling is distinguished among the methods of electrical diagnostics of semiconductors by the absence of special preparation of the structures and deposition of the contacts to perform measurements, thus providing for gaining information not only about the impurity distribution but also about the distribution of free carriers. The goal of this work is to perform precise measurements of the profiles of free carrier distribution in semiconductor structures of different types, and demonstrate the measuring capabilities of a modern technique for concentration distribution diagnostics, i.e., electrochemical capacitance-voltage profiling. The method allows verification of the layer thickness in semiconductor heterostructures and provide a useful and informative feedback to technologists. To increase the resolution of the method and broad up the range of available test frequencies, a standard electrochemical profiler has been modified. Mapping data for GaAs substrate structure, the profiles of the concentration distribution of the majority charge carriers in SiC structures, GaAs structure with a p – n junction, pHEMT heterostructure, GaN heterostructure with multiple quantum wells, and in a silicon-based solar cell heterostructure are presented. The obtained results can be used to analyze the physical properties and phenomena in semiconductor devices with quantum-sized layers, as well as to improve and refine the parameters of existing electronic devices.

A novel electrochemical profiling technique consisting in integration capacitance–voltage characteristics was proposed, developed and proven. The aim is to overcome the insufficient resolution in charge carrier concentration measurements during commonly used electrochemical capacitance–voltage profiling. This is very actual task for modern low-dimensional optoelectronics. According to the introduced “profiling window”, after each etching step the coordinate interval is selected, the concentration distribution in which is to be matched itself and by the first derivative at the edges with the concentration in adjacent intervals. To achieve these conditions the minimum dissipation factor should be maintained for each C–V characteristic at the corresponding etching depth. The method allows both to obtain general free charge carrier concentration depth distribution over unlimited structure depth and to achieve necessary resolution in key regions, even if they are lying at a high depth. Particularly, in GaAs-based heterostructure concentration profile of deep-lying quantum well and a delta layer (ultra-thin (2 nm) profile of dopant with extremely high concentration) were confidently distinguished with magnitude difference of 20% in the dip region in between. Besides, we have shown how quantum-confined objects of different origins give different concentration responses when electrochemical capacitance–voltage profiling with sequential etching. An explanation for this dissimilarity is given.

The near-surface “dead-layer” nature and its negative impact on back-side-illuminated charge-coupled devices (CCDs) have been investigated in detail. Special attention is devoted to the analysis of methods for the “dead-layer” eliminating. The study of this phenomenon was carried out using the technique of electrochemical capacitance–voltage profiling by measuring, simulating, and analyzing free charge carrier concentration profiles of back-side-illuminated CCDs, taken at various technological stages. Different techniques of annealing for ion implanted CCDs were used. By analyzing and comparison of free charge carriers concentration profiles, the recommendations for optimization of technology for back-thinned CCDs were proposed, aiming to increase of pulling field and decrease the impact of surface potential on charge carrier transport.

Introduction. In recent decades, in the field of photoelectronics, special attention has been paid to the development of semiconductor matrix photodetectors. These detectors have become an effective alternative to existing television receiving systems. Among such devices, linear position-sensitive sensors are used in cases where the rapid registration of changes to the environment is required (for instance, high-speed locators for flying vehicles).Aim. To develop a strip of silicon pin-diodes as part of a hybrid IR-detector for effective registration of photoelectrons with time resolution less than 10 ns, as well as to model the key electro-physical characteristics of the strip.Materials and methods. In the device under development, the registration of photoelectrons is achieved by the presence of a near-surface field using p ++–p junction formed by diffusion of boron into the silicon with resistivity of 3 kΩ · cm. The pulling field is also formed in the space charge region between p ++ - and n ++ -regions. Diffusion of phosphorus was carried out to create the n ++ -region. Numerical calculations of potential distribution, concentration of free charge carriers and currents were carried out using software for 1D- and 2D-modelling (SimWin and TCAD Synopsys).Results. 2D-calculation of charge carrier concentration and potential distribution was performed. The study determined the minimum bias for the complete depletion of the i-layer, including that for longitudinal grooves of various depths. The strip was tested as part of a hybrid photoelectric device by irradiating light pulses from IR LED. When the voltage on the diodes was reached –270 V, the duration of the signal front on all channels was 5…9 ns.Conclusion. For use in IR-hybrid detectors, a strip of 12 silicon pin-diodes was developed with a sensitive element of 24 × 0.2 mm in dimension. The study of pulse characteristics showed that the necessary duration of the front signal on all channels was achieved without thinning thus satisfying the requirements for high-speed position-sensitive sensor of the infrared radiation.

Gallium nitride transistors with high electron mobility (HEMT) have been studied by means of electrochemical capacitance–voltage (ECV) technique. The capacitance–voltage characteristics at various ...

Electrochemical capacitance–voltage profiling has been used to examine heterojunction solar cells based on single-crystal silicon. Specific features of the electrochemical capacitance–voltage profiling of modern multilayer heterojunction solar cells have been analyzed. The distribution profiles of majority carriers across the whole thickness of the samples were obtained, including, for the first time, those in layers of conducting indium tin oxide.

We present experimental and theoretical investigations of pHEMT heterostructures with AlGaAs/InGaAs/GaAs quantum wells (QWs) and/or a delta-doped layer, which can be used as active regions in transistors operating in the 4-18 GHz frequency range. Using the electrochemical capacitance-voltage setup ECV Pro we, for the first time, experimentally observed a concentration peak from the near-surface delta layer of the pHEMT structure together with a peak of QW enrichment. The capacitance of the electrolyte-semiconductor contact was measured by Agilent LCR-meter, which was connected to the electrochemical cell of ECV Pro through a specially designed relay module. Using numerical simulation of the electronic characteristics of nanoheterostructures by self-consistent solution of Schrodinger and Poisson equations we determined electrostatic potential profiles for band edges, band offsets, quantum-confinement levels, and concentration profiles of charge carriers for the samples under investigation. The impact of delta-layer position on the confined energy levels and carrier concentration in the QW was experimentally and theoretically analyzed in detail. We determined the optimal distance between the QW and delta layer, which provides the most efficient process of supply of charge carriers to the QW. The conducted work is directed at improvement of SHF devices, allowing one to increase the gain coefficient and transconductance of transistors.

The specific features of applying electrochemical capacitance–voltage profiling to investigate heavily doped structures with a sharp doping profile are considered. Criteria are presented, and recommendations are given for selection of the optimal measurement parameters, and the necessity of increasing the frequency, at which the capacitance is measured during profiling, is substantiated. The described procedure is considered by the example of profiling p-type silicon structures with ion implantation as well as n-GaAs epitaxial and substrate structures for pHEMT devices.

The paper provides experimental and theoretical study of pHEMT heterostructures with quantum well (QW) AlGaAs/InGaAs/GaAs and delta-doped layer used as active layers for fabrication of 4-18 GHz transistors. As the experimental techniques, the electrochemical capacitance-voltage (ECV) profiling and other methods of admittance spectroscopy are applied. Modernization of commercial ECV-profiling setup allows observing for the first time the concentration peak from a near-surface delta-layer of pHEMT heterostructures together with the enrichment peak from the quantum well. In order to optimize the etching speed the crater bottom control is performed by means of AFM. The electrolyte-semiconductor contact capacitance is measured with Agilent RLC-meter. The main theoretical technique used in the research is numerical modeling of nanoheterostructure key electronic features by self-consistent solution of Schrödinger and Poisson equations. The potential line-up for the conduction band bottom is obtained, and the quantized energy levels are calculated. The complex analysis of series of samples is carried out in order to understand the influence of delta-layer position on the level depth and at the carrier concentration. The optimum distance between QW and delta-layer providing the most efficient charge carrier delivery to quantum well is found. The performed research is aimed at improvement of microwave electronic devices allowing increase of the gain coefficient and the transfer characteristic of SHF-transistors.

Light-emitting heterostructures with single and multiple GaAs/InGaAs quantum wells have been investigated by means of electrochemical capacitance-voltage (ECV) profiling. Capacitance-voltage characteristics were measured; concentration profiles of free charge carriers over the heterostructure depth as well as the intensity of quantum well filling by charge carriers were obtained. In heterostructures with a single quantum well (QW), we considered limitations of capacitance techniques for undoped QW profiling, which are situated near the metallurgic border of the p-n junction. We made a detailed consideration of phenomena related to Debye smearing and we developed and analyzed the dependence of the space charge region width on the doping. Special attention was paid to investigation of "the blind" area. This was inspired by the practical problem from capacitance spectroscopy of semiconductors, when the researcher poses the task of obtaining a free charge carrier depth distribution profile as deep as possible in the space charge region, i.e. where the intensity of the electric field is maximum. Generally, the active QW of a LED heterostructure is placed deep in the space charge region, so reaching these regions is extremely important for practical problems. We present an evolution of capacitance-voltage characteristics during ECV profiling of nonuniformly doped p-n-heterostructures. For a heterostructure with multiple quantum wells, we registered a response from 6 QWs.

GaAs light-emitting (LED) and HEMT structures with δ-doped regions, InGaAs/GaAs quantum wells, and surface layers of InAs/GaAs quantum dots were studied by means of the electrochemical capacitance- voltage profiling technique. The concentration depth profiles of free charge carriers were obtained. Charges accumulated in quantum wells and quantum dots, as well as the doping levels of the emitter and δ layers were determined. The band structure and free carrier density distribution over the depth of the samples with different quantum well geometry were simulated. The specific features of electrochemical capacitance- voltage profiling in different heterostructure types are analyzed. A method of integration of capacitance- voltage curves at each etching stage was suggested. This method provides the efficient separation of responses from closely located layers, particularly the quantum well and δ layer.

AbstractWe performed numerical self-consistent solution of Schrödinger and Poisson equations for GaAs/InGaAs/AlGaAs pHEMT structures with quantum well. Based on the results we calculated optical transition matrix elements and photoluminescence spectra of such structures with the same design and different parameters (such as doping level and epitaxial layers width). In the photoluminescence spectra calculations three fitting parameters have been used. These parameters are GaAs/InGaAs valence band offset in strained quantum well, hole quasi Fermi level and inhomogeneous broadening. The PL peaks amplitudes and positions dependencies on the structure parameters were established. These dependencies can be used as the basis for pHEMT structure non-destructive diagnostics.

A resonant-tunneling conductivity was experimentally registered in a doped heterostructure with a single quantum well using admittance spectroscopy. Earlier, this effect was only realized in artificially created resonant tunneling structures, having four heterojunctions. A heterostructure with an In0.3Ga0.7As/GaAs quantum well was examined in the temperature range of 10–300 K. In admittance spectra, a competition of thermionic and tunneling escape mechanisms was noticed with a non-exponential Arrhenius plot. By means of numerical self-consistent simulations in a quantum box, we have shown the role of a quasi-bound level in resonant tunneling of electrons; in addition, the energies and wave functions of the quasi-bound state were derived in dependence on an applied bias. The modification of a transparency coefficient for a two-barrier Hartree potential as a function of the quantum well width and in dependence on the applied bias was also calculated. The resonant state took place only at symmetric barriers and disappeared, when the electric field tilted the barriers. The results can be used to develop a new type of resonant tunneling diodes and as a method for diagnostics of the tunnel effect in semiconductors.

Optical and transport properties of the heterostructure with the InAs/GaAs quantum dots doped with manganese or chromium atoms in the course of growth using metal-organic vapor phase epitaxy (MOVPE) are analyzed. Circularly polarized luminescence was obtained due to doping of quantum dots with the Mn or Cr atoms. The sign of the degree of circular polarization was found to depend on the dopant. The effect is interpreted using specific features of the radiative recombination in quantum dots in the presence of resident electrons and holes.

The admittance measurements of heterostructures with quantum wells (QW) InxGa1 – xAs/GaAs (0.19 ≤ x ≤ 0.3) precisely grown by the MOCVD method were carried out. By means of the admittance spectroscopy method, the resonant tunneling emission was for the first time registered as the determining mechanism inducing high-frequency conductance of doped heterostructures with QW, the separation of tunnel and resonant tunneling contributions was carried out, and the influence of tunnel component on the total rate of carrier emission from QW was analyzed. The self-consistent simulation of capacitance–voltage characteristics of the structures was performed, and the transmittance of the system formed by the Hartree potential around QW was calculated. Experimentally and by numerical calculations, it is shown that the probability of resonant tunneling emission decreases with increasing reverse bias due to the broken symmetry of the barriers.

The structure and operating principle of InGaAs photocathode in near-IR hybrid photo device are considered. The mechanisms leading to the degradation of the quantum efficiency of the photocathode are being studied. The rate of the quantum efficiency degradation of the photocathode is measured for three hybrid devices. The methods to reduce the degradation of the photocathode sensitivity are suggested.

The method of electrochemical capacitance–voltage profiling is used to study boron-implanted silicon structures for CCD matrices with backside illumination. A series of specially prepared structures with different energies and doses of ion implantation and also with various materials used for the coating layers (aluminum, silicon oxide, and their combinations) is studied. The profiles of the depth distribution of majority charge carriers of the studied structures are obtained experimentally. Also, using the Poisson equation and the Fredholm equation of the first kind, the distributions of the charge-carrier concentration and of the electric field in the structures are calculated. On the basis of the analysis and comparison of theoretical and experimental concentration profiles, recommendations concerning optimization of the structures’ parameters in order to increase the value of the pulling field and decrease the effect of the surface potential on the transport of charge carriers are suggested.

An apparatus for measuring nonequilibrium capacitance–voltage characteristics in semiconductor structures with electrolytic contacts is described. A pulse CV method was used in which a space-charge region in the deep-depletion mode was created via application of a bias-voltage pulse. Measuring the capacitance in a nonequilibrium mode makes it possible to avoid the formation of an inverse layer in an electrolyte–semiconductor system, whose presence leads to overestimation of the results of measuring the impurity concentration in narrow-band semiconductors. The possibility of applying this technique to measurements of the impurity concentration in weakly doped n-InAs is shown.

A set of single-crystal multisectorial diamond plates, cut from boron-doped high-pressure high-temperature (HPHT) grown crystals, was investigated using admittance spectroscopy methods. The results of admittance measurements demonstrate that the density of free charge carriers in one multisectorial crystal may differ by more than 50 times depending on the growth face and it correlates with boron concentration derived from IR absorption studies. For the first time we have obtained different activation energy for boron in sectors within one single crystal. Based on the experimental data, the difference in impurity capture coefficients along the (111) and (001) faces were numerically estimated for the established HPHT growth process.

A computer-controlled complex of admittance spectroscopy has been developed, which allows one to perform a non-destructive diagnostics of key electronic parameters of bulk semiconductors and nanoheterostructures. The complex is essential both for research of nanoobjects (quantum wells, quantum dots, wetting layers etc.), and at the stage of device production for control of growth parameters and concentrations during doping processes. The created computer-controlled complex realizes both data acquisition and processing.

A mathematical model of the radiation output from a LED structure is developed on the basis of the corpuscular Monte Carlo method. As a result of simulation of LED structures, regularities of the influence of the interfaces between the media and roughnesses introduced on these interfaces on the relative portion of the output radiation from the structure are obtained. Based on the analysis, specific recommendations are made on optimization of light emitting flip-chip-structures based on solid solutions of gallium nitride.

An automated system for integrated electrophysical and optical studies of semiconductor nanoheterostructures, which operates in a wide temperature range from 15 to 475 K, is designed. The setup is intended to measure the temperature and frequency admittance and electroluminescence spectra of light-emitting diode and laser chips formed on substrates of diameter up to 50.2 mm, and the distribution of parameters over the wafer. The setup includes the closed-cycle helium cryogenic station, LCR meter, and temperature controller. The characterization results of nanoheterostructures with InGaN/GaN multiple quantum wells, which are used for creating highly efficient white and blue light-emitting diodes, are presented.

We analyzed charge carrier concentration distribution and electron spectra of the AlGaAs/In0.22Ga0.78As/GaAs quantum well pHEMT structures using experimental methods (photoluminescence and electrochemical capacitance-voltage profiling) coupled with a numerical simulation. The results of the PL spectra simulation and ECV free charge carrier distributions for the AlGaAs/In0.22Ga0.78As/GaAs pHEMT structures with quantum wells are presented. Based on the results, we suggest optimized heterostructures in order to obtain higher electron localization and occupation of the quantum states. Particularly, the optimization of spacer and donor layers thickness does enlarge the blocking dymanic range (BDR) and decrease trird-order intermodulation that finally leads to better electromagnetic compatibility (EMC) and noise resistance of pHEMT device.

International audience; Precision admittance spectroscopy measurements were carried out over wide temperature and frequency ranges for a set of natural single crystal type IIb diamond samples. Peaks of conductance spectra vs. temperature and frequency were used to compute the Arrhenius plots, and activation energies were derived from these plots. The capacitance-voltage profiling was used to estimate the majority charge carrier concentration and its distribution into depth of the samples. Apparent activation energies between 315 and 325 meV and the capture cross section of about 10− 13 cm2 were found for samples with uncompensated boron concentrations in the range of 1 to 5 × 1016 cm− 3 (0.06–0.3 ppm). The obtained boron concentrations are in good coincidence with FTIR results for the samples. Also, a reason for the difference between the observed admittance activation energy and the previously reported ionization energy for the acceptor boron in diamond (0.37 eV) is proposed.

The effect of the electrostatic interaction of charges in multiple quantum wells of a doped heterostructure is studied by admittance spectroscopy methods and numerical self-consistent calculations. Samples containing three InGaAs/GaAs quantum wells each 7 nm thick, separated by 150-nm barriers, are studied in detail. The InAs content in the wells is 22, 16, and 11.5%. Experimentally and by simulation, it is shown that the effect of the relative carrier depletion in the middle quantum well occurs due to the joining of local spacecharge regions around the quantum wells and is accompanied by raise of the middle well potential. The quantitative characteristics of this effect are analyzed depending on temperature, barrier thickness, and dopant concentration.

Results of the development of a hybrid vacuum semiconductor photodetector for the near IR-range are presented. The device is based on InP/In0.53Ga0.47As/InP photocathode and electron-sensitive CCD matrix with the number of elements 768×580. In order for the minority charge carriers generated within 0.5 μm from the surface to reach the recording cells, the CCD matrix was thinned to about 30 μm. In addition, in the reverse side of the matrix the phosphorus impurity was implanted. This technique creates the necessary gradient of the electric field, which provides high efficient transport of minority charge carriers to the potential pits of the CCD matrix. At room temperature and continuous irradiation the measured threshold irradiance was registered at the level of 5·10−8 W/cm2 for the wavelength range λ = 1–1.5 μm.

The magnetic susceptibility tensor for a composite medium consisting of specially oriented anisotropic ferrite particles is calculated. The lower and upper boundaries of the frequency range are determined for partially ordered orientations of the anisotropy axes of ferrite particles.

A method of electrochemical capacitance-voltage profiling is used to characterize InGaN/GaN heterostructures with multiple quantum wells. Implementation of pulsed electrochemical etching allowed getting good planarity of etched surface despite of the high density of dislocations in GaN. The quality of etching, optimization of its parameters and independent check of etched depth were controlled by AFM measurements. Concentration profiles of InGaN/GaN QWs structures were evaluated then from capacitance-voltage measurements revealing several quantum wells with a period of 17 nm. (© 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

Propagation of magnetostatic waves in a tangentially magnetized ferrite plate with a normal uniaxial anisotropy under the conditions for the orientational phase transition of the second order is considered. Dispersion relations for quasi-surface and quasi-volume magnetostatic waves with the wave vector arbitrarily oriented in the plane of the plate have been obtained. The limiting frequencies of the regions of existence of both modes have been determined and the dependences of these frequencies on the anisotropy field and wave-vector orientation have been investigated.

On the basis of the designed complex of low-temperature admittance spectroscopy, the electron spectrum of semiconductor light emitting diode (LED) heterostructures with InGaN/GaN multiple quantum wells was investigated. The features of the construction of the measuring complex, as well as the technique of measurements of semiconductor nanoheterostructures and processing of admittance spectra, are presented.

The wide possibilities of admittance spectroscopy as a tool for the effective study of relaxation processes in quantum-sized heterostructures are demonstrated by the example of comprehensive investigations of InGaN/GaN semiconductor heterostructures with multiple quantum wells. The nature of emitting centers in InGaN/GaN nanoheterostructures was determined from the character of charge carrier relaxation, as revealed from the temperature spectra of conductance.

Charge is evaluated as a function of temperature, based on the analysis and nmathematical processing of experimental capacitance-voltage characteristics obtained in frequency range of 1 kHz to 1 MHz and temperature range of 320 to 10 K for samples of InGaAs/GaAs heterostructures with quantum wells (QWs) and ultrathin InAs/GaAs wetting layers specially prepared for admittance measurements. It is found that the charge in the QW determined by the apparent concentration profiles from experimental C-V characteristics monotonically increases compared with the charge in quantum wells.

Propagation of magnetostatic surface waves (MSSWs) in a ferrite plate magnetized by a spatially periodic transverse field has been considered. The parameters of MSSW propagation have been calculated by the Hamilton-Auld method. It is shown that only noncollinear MSSWs, whose wave-beam trajectories as well as wave numbers and angles, which determine the directions of the vectors of the phase and group velocities, are described by functions that are periodic in the direction of the wave propagation, can exist in this field. The period of these functions is determined by the period of the spatially periodic field. The frequency range of existence of the collinear waves is narrower than that of the waves in a uniformly magnetized plate. The characteristics of wave propagation in a nonuniform spatially periodic field are compared to the characteristics of wave propagation in nonuniform fields of known types.

The dynamic high-frequency tensor susceptibility of a composite medium consisting of independent chaotically oriented uniaxially anisotropic ferrite spheres is calculated by averaging over directions under the conditions of an orientation transition. It is established that the tensor magnetic susceptibility has all nine components, among which the maximum components are those responsible for oscillations of the magnetization vector in the directions perpendicular to the constant magnetic field. It is shown that these peculiarities of the tensor make it possible to analyze waves in the medium with the help of the methods known in the electromagnetics of gyrotropic media.

AlGaAs/InGaAs/GaAs and AlGaN/GaN HEMT heterostructures were investigated by means of electrochemical capacitance-voltage technique. A set of test structures were fabricated using various doping techniques: standard doping, δ-doping GaAs pHEMT and nondoping GaN HEMT. The concentration profiles of free charge carriers across the samples were experimentally obtained. The QW filling was analyzed and compared for different mechanisms of emitter doping and 2DEG origins.

For the first time, using a complex of admittance spectroscopy, light-emitting heterostructures with InGaN/GaN multiple quantum wells were studied in a wide temperature range of 6–300 K. Three peaks are found in the conductance spectra; these peaks correspond to emission of charge carriers from the quantum wells and point defects distributed in the semiconductor bulk. Two low-temperature peaks possess an anomalous behavior, specifically, the peak with a low value of apparent activation energy (17 meV) is shifted to higher temperatures compared with the higher-energy peak (30 meV). The latter is attributed to a bulk defect having anomalously large capture cross section σn = 1.5 × 10−11 cm2.

We study excitation of magnetostatic backward volume waves on the microstrip line. The relation between the current density in the line and the normal component of the magnetic induction is found. The impedance of the line per unit length, i.e., its reactance and radiation resistance per unit length, is represented as a functional of the current density. The dependence of the operating-wave radiation resistance on the transverse size of the line and the width of the dielectric gap is studied. The radiation resistances of multistrip array and meander-type converters of magnetostatic backward volume waves are calculated

Heterostructures with single strained InGaAs/GaAs quantum wells have been studied by measuring the capacitance-voltage characteristics in a wide range of temperatures and test signal frequencies. Based on the analysis of experimental capacitance-voltage characteristics, a temperature shift of the peak in the apparent profile of a majority carrier’s concentration is revealed and a quantitative model of this phenomenon is proposed. The effect of incomplete impurity ionization on the experimentally found quantum well’s charge is determined. It is established by numerical simulation and fitting of capacitance-voltage characteristics that the conduction band’s discontinuity for heterostructures with strained InxGa1 − xAs/GaAs quantum wells (x = 0.225) remains constant and equal to 172 ± 10 meV at temperatures from 320 to 100 K.

Radiation of the electromagnetic waves accompanying propagation of a magnetostatic surface wave with nonparallel directions of the phase and group velocities in a ferrite slab magnetized in its plane by a transverse linearly increasing magnetic field is analyzed using the model of accelerated motion of magnetic charges. It is shown that, at each point of the space surrounding the ferrite slab, the shape of the radiation pattern strongly depends on the angle between the direction perpendicular to the direction of propagation of the magnetic field and the direction of the wave vector of the magnetostatic surface wave.

The method of C-V profiling combined with self-consistent solution of Schrodinger’s and Poisson’s equations was used to determine with high precision the absolute values of the conduction-band offsets, energies of quantum-confinement levels, and charge-carrier concentrations in quantum-confinement subbands of In x Ga1−x As/GaAs quantum-well heterostructures with In content corresponding to the pseudomorphic growth mode (0 < x < 0.3). A characterization technique based on capacitance measurements is developed, enabling one to determine the main electronic parameters of quantum-confinement heterostructures.

The dispersion characteristics (dispersion and isofrequency curves and dispersion surfaces) of magnetostatic surface waves propagating in an arbitrary direction in a two-layer ferromagnetic film are investigated. The shapes of these curves and surfaces are studied at different ratios between the saturation magnetizations of the ferromagnetic layers, and the conditions for existence of external waves (always forward) and internal waves (forward and backward or only forward) are determined.

The dispersion relation for magnetostatic surface waves in a ferrite/dielectric/metal-strip-grating structure is obtained. It is shown that dispersion of magnetostatic surface waves must be qualitatively the same as in a ferrite/dielectric/metal structure, while the slope of the dispersion curve in the region of backward magnetostatic waves existing in a ferrite/dielectric/grating structure (and in a ferrite/grating structure in particular) is considerably higher than the slope of this curve corresponding to a ferrite/dielectric/metal structure. It is found that this phenomenon can be explained by the dependence of the grating’s shielding capability on the wave number of magnetostatic surface waves. A grating shielding parameter is introduced and dependences of this parameter on the wave number that can be used to explain the phenomena observed in the experiment are determined.

Emission of electrons from localized electron states in InAs/GaAs self-organized quantum dots (QDs) grown by MOCVD has been studied by a combination of steady-state voltage–capacitance and admittance techniques. We have found a fine structure of carrier concentration profile in the area of QDs, which may be attributed to ground and excited energy states of electrons in the QDs. The total range of activation energies detected in the admittance investigations extends from 20 meV up to 140 meV and testifies to the significant inhomogeneous broadening of the density of state function due to the QD scattering in geometric sizes.