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1.	Agekyan, V F, et al. (författare) Magnetoluminescence of CdTe/MnTe/CdMgTe heterostructures with ultrathin MnTe layers 2011 Ingår i: Semiconductors (Woodbury, N.Y.). - : MAIK Nauka/Interperiodica (and#1052;and#1040;and#1048;and#1050; and#1053;and#1072;and#1091;and#1082;and#1072;/and#1048;and#1085;and#1090;and#1077;and#1088;and#1087;and#1077;and#1088;and#1080;and#1086;and#1076;and#1080;and#1082;and#1072;). - 1063-7826 .- 1090-6479. ; 45:10, s. 1301-1305 Tidskriftsartikel (refereegranskat)abstract CdTe/MnTe/CdMgTe quantum-well structures with one or two monolayers of MnTe inserted at CdTe/CdMgTe interfaces were fabricated. The spectra of the excitonic luminescence from CdTe quantum wells and their variation with temperature indicate that introduction of ultrathin MnTe layers improves the interface quality. The effect of a magnetic field in the Faraday configuration on the spectral position of the exciton-emission peaks indicates that frustration of magnetic moments in one-monolayer MnTe insertions is weaker than in two-monolayer insertions. The effect of a magnetic field on the exciton localization can be explained in terms of the exciton wave-function shrinkage and obstruction of the photoexcited charge-carrier motion in the quantum well.
2.	Averkiev, N S, et al. (författare) Spin relaxation in asymmetrical heterostructures 2002 Ingår i: Semiconductors (Woodbury, N.Y.). - : Springer Science Business Media. - 1063-7826 .- 1090-6479. ; 36:1, s. 91-97 Tidskriftsartikel (refereegranskat)abstract Electron spin relaxation by the Dyakonov-Perel mechanism is investigated theoretically in asymmetrical III-V heterostructures. Spin relaxation anisotropy for all three dimensions is demonstrated for a wide range of structural parameters and temperatures. Dependences of spin relaxation rates are obtained both for a GaAs-based heterojunctions and triangular quantum wells. The calculations show a several-orders-of-magnitude difference between spin relaxation times for heterostructure parameters realized in experiments.
3.	Belonovskii, A. V., et al. (författare) Strong Coupling of Excitons in Hexagonal GaN Microcavities 2020 Ingår i: Semiconductors (Woodbury, N.Y.). - : PLEIADES PUBLISHING INC. - 1063-7826 .- 1090-6479. ; 54:1, s. 127-130 Tidskriftsartikel (refereegranskat)abstract The GaN planar hexagonal microcavities are grown by the selective vapor-phase epitaxy technique. The spectra are measured by the low-temperature cathodoluminescence method using a scanning electron microscope. The obtained spectra show a huge Rabi splitting (similar to 100 meV). Numerical simulation of the spatial distribution of the intensities of modes in a hexagonal cavity is carried out. Certain modes can have a high spatial localization leading to strong coupling with the exciton and huge Rabi splitting. The fraction of excitons in polariton modes, which correlates with the intensity of exciton radiation associated with these modes, is theoretically calculated for hexagonal-shaped microcavities. Thus, the form of the dependence of the radiation probability on the eigenfrequencies of the structure is obtained.
4.	Davydov, S.Yu., et al. (författare) A Simple Model for Calculating the Growth Rate of Epitaxial Layers of Silicon Carbide in Vacuum 2004 Ingår i: Semiconductors (Woodbury, N.Y.). - : American Institute of Physics (AIP). - 1063-7826 .- 1090-6479. ; 38:2, s. 150-152 Tidskriftsartikel (refereegranskat)abstract The temperature dependence of the growth rate of epitaxial layers of silicon carbide in vacuum was calculated within the simple model based on the Hertz-Knudsen equation, taking into account the temperature-dependent sticking coefficient. The calculation results fit the experimental data well. © 2004 MAIK "Nauka/Interperiodica".
5.	Gubaydullin, A. R., et al. (författare) Purcell Effect in Tamm Plasmon Structures with QD Emitter 2018 Ingår i: Semiconductors (Woodbury, N.Y.). - : MAIK NAUKA/INTERPERIODICA/SPRINGER. - 1063-7826 .- 1090-6479. ; 52:4, s. 452-457 Tidskriftsartikel (refereegranskat)abstract We study Tamm plasmon structure based on GaAs/Al0.95GaAs distributed Bragg reflector covered by thin silver layer, with active area formed by InAs quantum dots. We have measured the spectral and angular characteristics of photoluminescence and performed theoretical calculation of the spontaneous emission rate (modal Purcell factor) in the structure by using S-quantization formalism. We show that for Tamm plasmon mode the spontaneous emission can be enhanced by more than an order of magnitude, despite absorption in metallic layer.
6.	Jmerik, V. N., et al. (författare) Site-Controlled Growth of GaN Nanorods with Inserted InGaN Quantum Wells on mu-Cone Patterned Sapphire Substrates by Plasma-Assisted MBE 2018 Ingår i: Semiconductors (Woodbury, N.Y.). - : MAIK NAUKA/INTERPERIODICA/SPRINGER. - 1063-7826 .- 1090-6479. ; 52:5, s. 667-670 Tidskriftsartikel (refereegranskat)abstract We report on a new approach to fabricate regular arrays of GaN nanorods (NRs) with InGaN QWs by plasma-assisted molecular-beam epitaxy (PA MBE) on micro-cone patterned sapphire substrates (mu-CPSSs). A two-stage PA MBE fabrication process of GaN NRs has been developed, starting with a high temperature nucleation layer growth at metal-rich conditions to aggregate selectively GaN nucleus on c-oriented areas of the mu-CPSSs and followed by growth of 1-mu m-thick GaN NRs at strongly nitrogen-rich conditions exactly on the cone tips. These results are explained by energetically favorable GaN growth on the (000 (1) over bar) oriented sapphire surface. Both micro-photoluminescence and micro-cathodoluminescence confirm the formation of regular array of optically and spectrally isolated NRs without usage of any nanolithography.
7.	Kalinina, E. V., et al. (författare) Effect of irradiation with fast neutrons on electrical characteristics of devices based on CVD 4H-SiC epitaxial layers 2003 Ingår i: Semiconductors (Woodbury, N.Y.). - : Pleiades Publishing Ltd. - 1063-7826 .- 1090-6479. ; 37:10, s. 1229-1233 Tidskriftsartikel (refereegranskat)abstract The effect of irradiation with 1-MeV neutrons on electrical properties of Al-based Schottky barriers and p(+)-n-n(+) diodes doped by ion-implantation with Al was studied; the devices were formed on the basis of high-resistivity, pure 4H-SiC epitaxial layers possessing n-type conductivity and grown by vapor-transport epitaxy. The use of such structures made it possible to study the radiation defects in the epitaxial layer at temperatures as high as 700 K. Rectifying properties of the diode structures were no longer observed after irradiation of the samples with neutrons with a dose of 6 x 10(14) cm(-2); this effect is caused by high (up to 50 GOmega) resistance of the layer damaged by neutron radiation. However, the diode characteristics of irradiated p(+)-n-n(+) structures were partially recovered after an annealing at 650 K.
8.	Kalinina, E. V., et al. (författare) Optical and electrical properties of 4H-SiC irradiated with fast neutrons and high-energy heavy ions 2004 Ingår i: Semiconductors (Woodbury, N.Y.). - : Pleiades Publishing Ltd. - 1063-7826 .- 1090-6479. ; 38:10, s. 1187-1191 Tidskriftsartikel (refereegranskat)abstract Photoluminescence and deep-level transient spectroscopy are used to study the effect of irradiation with fast neutrons and high-energy Kr (235 MeV) and Bi (710 MeV) ions on the optical and electrical properties of high-resistivity high-purity n-type 4H-SiC epitaxial layers grown by chemical vapor deposition. Electrical characteristics were studied using the barrier structures based on these epitaxial layers: Schottky barriers with Al and Cr contacts and p(+)-n-n(+) diodes fabricated by Al ion implantation. According to the experimental data obtained, neutrons and high-energy ions give rise to the same defect-related centers. The results show that, even for the extremely high ionization density (34 keV/nm) characteristic of Bi ions, the formation of the defect structure in SiC single crystals is governed by energy losses of particles due to elastic collisions.
9.	Kibis, O. , V, et al. (författare) Topological Electronic States on the Surface of a Strained Gapless Semiconductor 2019 Ingår i: Semiconductors (Woodbury, N.Y.). - : Pleiades Publishing Inc. - 1063-7826 .- 1090-6479. ; 53:14, s. 1867-1869 Tidskriftsartikel (refereegranskat)abstract We develop the theory describing the topological electronic states on the surface of a gapless strained semiconductor arisen from the mixing of conduction and valence bands. It follows from the present theory that the strain-induced band gap in the Brillouin zone center of the semiconductor results in the surface electronic states with the Dirac linear dispersion characteristic for topologically protected states. The structure of these surface electronic states is studied analytically near their Dirac point within the formalism based on the Luttinger Hamiltonian. The results bring attention to the rich surface physics relevant for topological systems.
10.	Lebedev, A.A., et al. (författare) Radiation hardness of wide-gap semiconductors (using the example of silicon carbide) 2002 Ingår i: Semiconductors (Woodbury, N.Y.). - : Pleiades Publishing Ltd. - 1063-7826 .- 1090-6479. ; 36:11, s. 1270-1275 Tidskriftsartikel (refereegranskat)abstract Results obtained in studying the effect of ionizing radiation on epitaxial layers and devices based on silicon carbide (SiC) are considered. It is shown that, in investigations of wide-gap semiconductors (WGS), account should be taken of how the rate of removal of mobile charge carriers - the standard parameter in determining the radiation hardness of a material - depends on temperature. The use of data obtained only at room temperature may lead to an incorrect assessment of the radiation hardness of WGS. A conclusion is made that the WGS properties combine, on the one hand, high radiation hardness of high-temperature devices based on these semiconductors and, on the other, the possibility of effective radiation-induced doping (e.g., for obtaining semi-insulating local regions in a material at room temperature). © 2002 MAIK "Nauka/Interperiodica".
11.	Lebedev, Alexander, 2000-, et al. (författare) A study of thick 3C-SiC epitaxial layers grown on 6H-SiC substrates by sublimation epitaxy in vacuum 2007 Ingår i: Semiconductors (Woodbury, N.Y.). - 1063-7826 .- 1090-6479. ; 41:3, s. 263-265 Tidskriftsartikel (refereegranskat)abstract 3C-SiC epitaxial layers with a thickness of up to 100 μm were grown on 6H-SiC hexagonal substrates by sublimation epitaxy in vacuum. The n-type epitaxial layers with the area in the range 0.3-0.5 cm2 and uncompensated donor concentration N d - N a ∼ (10 17-1018) cm-3 were produced at maximum growth rates of up to 200 μm/h. An X-ray analysis demonstrated that the epitaxial layers are composed of the 3C-SiC polytype, without inclusions of other polytypes. The photoluminescence (PL) spectrum of the layers was found to be dominated by the donor-acceptor (Al-N) recombination band peaked at hv ≈ 2.12 eV. The PL spectrum measured at 6 K was analyzed in detail. It is concluded that the epitaxial layers obtained can serve as substrates for 3C-SiC-based electronic devices. © Nauka/Interperiodica 2007.
12.	Lebedev, Alexander, et al. (författare) Structural defects and deep-level centers in 4H-SiC epilayers grown by sublimational epitaxy in vacuum 2000 Ingår i: Semiconductors (Woodbury, N.Y.). - 1063-7826 .- 1090-6479. ; 34:10, s. 1133-1136 Tidskriftsartikel (refereegranskat)abstract The parameters of deep-level centers in lightly doped 4H-SiC epilayers grown by sublimational epitaxy and CVD were investigated. Two deep-level centers with activation energies E-c - 0.18 eV and E-c - 0.65 eV (Z1 center) were observed and tentatively identified with structural defects of the SiC crystal lattice. The Z1 center concentration is shown to fall with decreasing uncompensated donor concentration N-d - N-a in the layers. For the same N-d - N-a, the Z1 center concentration is lower in layers with a higher dislocation density. (C) 2000 MAIK "Nauka/Interperiodica".
13.	Litvinov, VV, et al. (författare) Local vibrational modes of the oxygen-vacancy complex in germanium 2002 Ingår i: Semiconductors. - : Pleiades Publishing Ltd. - 1063-7826 .- 1090-6479. ; 36:6, s. 621-624 Tidskriftsartikel (refereegranskat)abstract Infrared absorption of n- and p-Ge crystals enriched with O-16 and/or O-18 isotopes was studied after irradiation with 6-MeV electrons. Absorption spectra were measured at 10 and 300 K. Along with known bands characteristic of oxygen-containing defects, new lines at 669, 944, and 990 cm(-1) were detected. These bands are annealed at temperatures of 120-140degreesC; the band at 621 cm(-1), previously related to the vacancy-oxygen complex in Ge, is simultaneously annealed. The bands at 621 and 669 cm(-1) showed identical temperatures (10 --> 300 K) and oxygen isotope (O-16 --> O-18) shifts. These bands were found to correspond to various charge states of a defect with an energy level near E-v = 0.25 +/- 0.03 eV. It is assumed that such a defect is the vacancy-oxygen complex (A center). The weak bands at 944 and 990 cm(-1) were identified as combinations of asymmetric stretching modes at 621 and 669 cm(-1) with a symmetric one at 320 cm(-1) for neutral and negative charge states of the A center, respectively.
14.	Lubenschenko, A., et al. (författare) Air-Oxidation of Nb Nano-Films 2018 Ingår i: Semiconductors. - 1090-6479 .- 1063-7826. ; 52:5, s. 678-682 Tidskriftsartikel (refereegranskat)abstract X-ray photoelectron spectroscopy (XPS) depth chemical and phase profiling of air-oxidized niobium nanofilms has been performed. It is found that oxide layer thicknesses depend on the initial thickness of the niobium nanofilm. The increase in thickness of the initial Nb nano-layer is due to increase in thickness of an oxidized layer.
15.	Mikhaylov, Aleksey I., et al. (författare) On the ion implantation of phosphorus as a method for the passivation of states at the interface between 4H-SiC and SiO2 produced by thermal oxidation in dry oxygen 2014 Ingår i: Semiconductors (Woodbury, N.Y.). - : Maik Nauka-Interperiodica Publishing. - 1063-7826 .- 1090-6479. ; 48:12, s. 1581-1585 Tidskriftsartikel (refereegranskat)abstract A method is suggested for reducing the density of surface states at the 4H-SiC/SiO2 interface by the implantation of phosphorus ions into a 4H-SiC epitaxial layer immediately before the growth of a gate insulator in an atmosphere of dry oxygen. A significant decrease in the density of surface states is observed at a phosphor-ion concentration at the SiO2/SiC interface exceeding 1018 cm−3. However, together with the passivation of surface states, the introduction of phosphorus ions leads to an increase in the built-in charge in the insulator and also slightly deteriorates the reliability of the gate insulator fabricated by this technique.
16.	Mikhaylova, A. I., et al. (författare) Specific features of the current–voltage characteristics of SiO2/4H-SiC MIS structures with phosphorus implanted into silicon carbide 2016 Ingår i: Semiconductors (Woodbury, N.Y.). - 1063-7826 .- 1090-6479. ; 50:1, s. 103-105 Tidskriftsartikel (refereegranskat)abstract The effect of phosphorus implantation into a 4H-SiC epitaxial layer immediately before the thermal growth of a gate insulator in an atmosphere of dry oxygen on the reliability of the gate insulator is studied. It is found that, together with passivating surface states, the introduction of phosphorus ions leads to insignificant weakening of the dielectric breakdown field and to a decrease in the height of the energy barrier between silicon carbide and the insulator, which is due to the presence of phosphorus atoms at the 4H-SiC/SiO2 interface and in the bulk of silicon dioxide.
17.	Moskalenko, S. A., et al. (författare) Metastable Bound States of the Two-Dimensional Bimagnetoexcitons in the Lowest Landau Levels Approximation 2018 Ingår i: Semiconductors (Woodbury, N.Y.). - : PLEIADES PUBLISHING INC. - 1063-7826 .- 1090-6479. ; 52:14, s. 1801-1805 Tidskriftsartikel (refereegranskat)abstract The possible existence of the bound states of the interacting two-dimensional (2D) magnetoexcitons in the lowest Landau levels (LLLs) approximation was investigated using the Landau gauge description. The magnetoexcitons taking part in the formation of the bound state with resultant wave vector have opposite in-plane wave vectors and and look as two electric dipoles with the arms oriented in-plane perpendicularly to the corresponding wave vectors. The bound state of two antiparallel dipoles moving with equal probability in any direction of the plane with equal but antiparallel wave vectors is characterized by the variational wave function of the relative motion depending on the modulus . The spins of two electrons and the effective spins of two holes forming the bound states were combined separately in the symmetric or in the antisymmetric forms with the same parameter for electrons and holes. In the case of the variational wave function the maximum density of the magnetoexcitons in the momentum space representation is concentrated on the in-plane ring with the radius The stable bound states of the bimagnetoexciton molecule do not exist for both spin orientations. Instead of them, a deep metastable bound state with the activation barrier comparable with the ionization potential of the magnetoexciton with was revealed in the case and . In the case and only a shallow metastable bound state can appear.
18.	Moskalenko, S. A., et al. (författare) Two-Dimensional Electron-Hole System under the Influence of the Chern-Simons Gauge Field Created by the Quantum Point Vortices 2021 Ingår i: Semiconductors (Woodbury, N.Y.). - : Pleiades Publishing Ltd. - 1063-7826 .- 1090-6479. ; 55:SUPPL 1, s. S35-S48 Tidskriftsartikel (refereegranskat)abstract The Chern-Simons (CS) gauge field theory was widely used to explain and to deeper understand the fractional quantum Hall effects. In this work, we apply the Chern-Simons gauge field theory to a two-dimensional (2D) electron-hole (e-h) system in a strong perpendicular magnetic field under the influence of the quantum point vortices creating by the Chern-Simons (CS) gauge field. The composite electron-hole particles with equal integer positive numbers phi of the attached quantum point vortices are described by the dressed field operators that obey to either the Fermi or Bose statistics depending on the even or odd numbers phi. It is shown that the phase operators, as well as the vector and scalar potentials of the CS gauge field, depend on the difference between the electron and the hole density operators. They vanish in the mean field approximation, when the average values of the electron and of the hole densities coincide. Nevertheless, even in this case, quantum fluctuations of the CS gauge field lead to new properties of the 2D e-h system. It is found that the numbers of vortices attached to each electron and hole are the same. This result is not obvious, and a different distribution of vortices in the environment of electron-hole pairs could be expected. A simple analytical formula is obtained for the shift of the magnetoexciton energy level at the point k = 0 due to the influence of the CS gauge field.
19.	Pozina, Galia, et al. (författare) Experimental Study of Spontaneous Emission in Bragg Multiple- Quantum-Well Structures with InAs Single-Layer Quantum Wells 2018 Ingår i: Semiconductors (Woodbury, N.Y.). - : PLEIADES PUBLISHING INC. - 1063-7826 .- 1090-6479. ; 52:7, s. 877-880 Tidskriftsartikel (refereegranskat)abstract The time-resolved photoluminescence of a Bragg structure formed by InAs single-layer quantum wells in a GaAs matrix is investigated experimentally. The comparison of photoluminescence spectra recorded from the edge and the surface of the sample indicates that Bragg ordering of the quantum wells leads to substantial modification of the spectra, in particular, to the appearance of additional modes. The spectrum recorded at the edge of the sample features a single line corresponding to the exciton ground state. In the spectrum recorded at the surface, an additional line whose frequency and propagation angle correspond to the Bragg condition for quantum wells, appears at high excitation levels. The calculation of the modal Purcell factor explains the fact that spontaneous emission is enhanced only for specific propagation angles and frequencies, rather than for all angles and frequencies satisfying the Bragg condition.
20.	Pozina, Galia, et al. (författare) Experimental Study of Spontaneous Emission in the Bragg Multiple Quantum Wells Structure of InAs Monolayers Embedded in a GaAs Matrix 2018 Ingår i: Semiconductors (Woodbury, N.Y.). - : PLEIADES PUBLISHING INC. - 1063-7826 .- 1090-6479. ; 52:14, s. 1822-1826 Tidskriftsartikel (refereegranskat)abstract Time-resolved photoluminescence of a Bragg structure of InAs-monolayer quantum wells in GaAs matrix was experimentally studied with. Comparison of luminescence patterns from the side and from the surface of a sample showed that Bragg-type ordering of quantum wells leads to a substantial alteration of the photoluminescence spectra including appearance of additional radiative modes. The sample side spectrum contains a single line corresponding to a ground state of an exciton. The surface spectrum at high excitation levels a new radiation line appears whose frequency and propagation angle correspond to the Bragg condition for quantum wells. A numerical calculation of the modal Purcell factor explains why the radiative emission amplification occurs only at a set of specific angles and frequencies, as opposed to the whole range that satisfies the Bragg condition.
21.	Strokan, N.B., et al. (författare) Measurement of micrometer diffusion lengths by nuclear spectrometry 2005 Ingår i: Semiconductors (Woodbury, N.Y.). - : Pleiades Publishing Ltd. - 1063-7826 .- 1090-6479. ; 39:12, s. 1394-1398 Tidskriftsartikel (refereegranskat)abstract A method for determination of diffusion lengths in the range 0.5-50 µm, which corresponds to carrier lifetimes in the nanosecond range, is suggested A calibrated nonequilibrium charge is injected into the base of the reverse-biased diode structure. The injection is provided by alpha particles generated by natural decay in the single-particle counting mode. The nuclear spectrometry technique is used to measure the amount of charge that diffused across the base to the boundary of the electric-field region. The loss of charge during the diffusion is calculated as a function of the depth of alpha particle penetration beyond the electric-field region. The derived power-law functions make it possible to relate the diffusion length with the exponent and numerical factor that describes the loss of charge. The experiment is performed with lightly doped 4H-SiC epitaxial films. © 2005 Pleiades Publishing, Inc.
22.	Strokan, N.B., et al. (författare) Radiation resistance of transistor- and diode-type SiC detectors irradiated with 8-MeV protons 2004 Ingår i: Semiconductors (Woodbury, N.Y.). - : Pleiades Publishing Ltd. - 1063-7826 .- 1090-6479. ; 38:7, s. 807-811 Tidskriftsartikel (refereegranskat)abstract Nuclear-particle detectors based on SiC with a structure composed of an n+-type substrate, a p-type epitaxial layer, and a Schottky barrier are studied. Structures with a ~10-µm-thick 6H-SiC layer exhibit transistor properties, whereas those with a ~30-µm-thick 4H-SiC layer exhibit diode properties. It is established that a more than tenfold amplification of the signal is observed in the transistor-type structure. The amplification is retained after irradiation with 8-MeV protons with a dose of at least 5 × 1013 cm-2, in this case, the resolution is =10%. Amplification of the signal was not observed in the structures of diode type. However, there were diode-type detectors with a resolution of ˜3%, which is acceptable for a number of applications, even after irradiation with the highest dose of 2 × 1014 cm-2. © 2004 MAIK "Nauka/Interperiodica".
23.	Strokan, N.B., et al. (författare) Silicon carbide transistor structures as detectors of weakly ionizing radiation 2003 Ingår i: Semiconductors (Woodbury, N.Y.). - : Pleiades Publishing Ltd. - 1063-7826 .- 1090-6479. ; 37:1, s. 65-69 Tidskriftsartikel (refereegranskat)abstract SiC-based nuclear radiation detectors figured prominently in the very first attempts of the 1960s to replace gas in ionization chambers with a more condensed semiconducting medium. However, the dynamics of improvement of SiC in those years was markedly inferior to the progress made in the development of competing materials. This study continues with the investigation of triode detector structures based on "pure" SiC films. It is established that for weakly ionizing radiation (as also in the case of strongly ionizing alpha particles) the signal is amplified by no less than a factor of several tens. This allows SiC films with a thickness of about 10 µm to be used to detect penetrating radiation, e.g., X-rays, since the effective thickness of the films is on the order of hundreds of micrometers. © 2003 MAIK "Nauka/Interperiodica".
24.	Strokan, N.B., et al. (författare) The limiting energy resolution of SiC detectors in ion spectrometry 2005 Ingår i: Semiconductors (Woodbury, N.Y.). - : Pleiades Publishing Ltd. - 1063-7826 .- 1090-6479. ; 39:12, s. 1420-1425 Tidskriftsartikel (refereegranskat)abstract The Monte Carlo method is used to simulate the complete stopping of a particles in SiC. A histogram of energy losses in nuclear-scattering events is obtained. The energy-loss spectrum has the characteristic asymmetric shape with the line full width at the half-maximum FWHMnucl ˜ 4. 22 keV. The final shape of the spectral line is obtained by a convolution with the Gaussian function that describes the contribution of the ionization and noise fluctuations (originated in the detector and instrumentation) to the signal. The resulting value of FWHM for the line is equal to 8.75 keV (at a noise variance of 1.7 keV). The experimental energy resolution of the detectors was found to be poorer than the calculated value by a factor of 2. It is established that the losses of charge during its transport in the detector bulk are insignificant, so that the discrepancy between the calculated and experimental values of the resolution should be attributed to the nonoptimal design of the detector window. © 2005 Pleiades Publishing, Inc.
25.	Tkachman, M.G., et al. (författare) Phonon-assisted exciton luminescence in GaN layers grown by MBE and chloride-hydride VPE 2003 Ingår i: Semiconductors (Woodbury, N.Y.). - : Pleiades Publishing Ltd. - 1063-7826 .- 1090-6479. ; 37:5, s. 532-536 Tidskriftsartikel (refereegranskat)abstract Optical properties of GaN layers grown by the molecular-beam epitaxy (MBE) and chloride-hydride vapor-phase epitaxy (CHVPE) have been studied, and the quality of two types of samples has been compared. The photoluminescence spectra have an excitonic nature for both types of layers. To determine precisely the nature of exciton transitions, the reflectance spectra were studied. A key point was the investigation of phonon-assisted exciton luminescence, which provides information on the density distribution of the exciton states. Temperature dependences of the exciton transition energy and the ratio of intensities of one- and two-phpnon replicas were studied. The high quality of both types of layers has been confirmed, though the concentration of acceptors in MBE-grown samples is higher than in CHVPE samples. © 2003 MAIK "Nauka/Interperiodica".
26.	Toropov, A. A., et al. (författare) ZnMnSe/ZnSSe Type-II semimagnetic superlattices : Growth and magnetoluminescence properties 2002 Ingår i: Semiconductors (Woodbury, N.Y.). - : Pleiades Publishing Ltd. - 1063-7826 .- 1090-6479. ; 36:11, s. 1288-1293 Tidskriftsartikel (refereegranskat)abstract A ZnSSe/ZnMnSe type-II semimagnetic superlattice was pseudomorphically grown via molecular beam epitaxy on a GaAs substrate. The superlattice-layer thicknesses and compositions were chosen so that compressive strains in the ZnMnSe layer compensated tensile strains in the ZnSSe layer. The photoluminescence spectra in an external magnetic field demonstrate the effect of giant Zeeman splitting of an exciton. Simulation of the luminescence-line shift in a magnetic field allowed us to determine more accurately the band offsets at the ZnSSe/ZnMnSe interface.
27.	Violina, G. N., et al. (författare) Photoelectric properties of p(+)-n junctions based on 4H-SiC ion-implanted with aluminum 2002 Ingår i: Semiconductors (Woodbury, N.Y.). - : Pleiades Publishing Ltd. - 1063-7826 .- 1090-6479. ; 36:6, s. 706-709 Tidskriftsartikel (refereegranskat)abstract The photoelectric properties of p(+)-n junctions that were based on 4H-SiC ion-implanted with aluminum and were formed in lightly doped n-type epitaxial layers grown by chemical vapor deposition were studied. It is shown that such photodetectors combine in full measure the advantages of photostructures formed on the basis of Schottky barriers and epitaxial p-n junctions. The results of the theoretical calculation of spectral characteristics of ion-implanted photodetectors are in good agreement with experimental data. The structures feature an efficiency of collection of nonequilibrium charge carriers close to 100% in the spectral range of the photon energies of 3.5-4.25 eV.
28.	Violina, G. N., et al. (författare) Silicon carbide detectors of high-energy particles 2002 Ingår i: Semiconductors (Woodbury, N.Y.). - : Pleiades Publishing Ltd. - 1063-7826 .- 1090-6479. ; 36:6, s. 710-713 Tidskriftsartikel (refereegranskat)abstract The results of studying 4H-SiC p(+)-n junctions ion-implanted with aluminum as detectors of high-energy particles are reported. The junctions were formed in SiC epitaxial films grown by chemical vapor deposition. The concentration of uncompensated donors was (3-5) x 10(15) cm(-3), and the charge-carrier diffusion length was L-p = 2.5 mum. The detectors were irradiated with 4.8-5.5-MeV alpha particles at 20degreesC. The efficiency of collection of the induced charge was as high as 0.35. The possibilities of operating SiC detectors at elevated temperatures (similar to500degreesC) are analyzed.
29.	Zhukavin, R. Kh, et al. (författare) Terahertz-range spontaneous emission under the optical excitation of donors in uniaxially stressed bulk silicon and SiGe/Si heterostructures 2015 Ingår i: Semiconductors (Woodbury, N.Y.). - 1063-7826 .- 1090-6479. ; 49:1, s. 13-18 Tidskriftsartikel (refereegranskat)abstract The results of measurements of the total terahertz-range photoluminescence of Group-V donors (phosphorus, antimony, bismuth, arsenic) in bulk silicon and SiGe/Si heterostructures depending on the excitation intensity are presented. The signal of bulk silicon was also measured as a function of uniaxial stress. The results of measurement of the dependence of the spontaneous emission intensity on the uniaxial stress is in rather good agreement with theoretical calculations of the relaxation times of excited states of donors in bulk silicon. Comparative measurements of the spontaneous emission from various strained heterostructures showed that the photoluminescence signal is caused by donor-doped silicon regions.
30.	Medvedkin, G A, et al. (författare) Optoelectronic images of polycrystalline thin-film solar cells based on CuInSe2 and CuInGaSe2 obtained by laser scanning 1999 Ingår i: SEMICONDUCTORS. - 1063-7826. ; 33:9, s. 1037-1039 Tidskriftsartikel (refereegranskat)abstract The laser scanning technique was used to obtain two- and three-dimensional optoelectronic images of polycrystalline solar cells based on thin films of CuInSe2 and CuInGaSe2. Topograms obtained with the aid of the laser-beam-induced current reveal microreg
31.	Solovan, M. N., et al. (författare) Graphite/p-SiC Schottky Diodes Prepared by Transferring Drawn Graphite Films onto SiC 2018 Ingår i: Semiconductors. - 1063-7826. ; 52:2, s. 236-241 Tidskriftsartikel (refereegranskat)abstract Graphite/p-SiC Schottky diodes are fabricated using the recently suggested technique of transferring drawn graphite films onto p-SiC single-crystal substrates. The current–voltage and capacitance–voltage characteristics are measured at different temperatures and at different frequencies of a small-signal AC signal, respectively. The temperature dependences of the potential-barrier height and of the series resistance of the graphite/p-SiC junctions are measured and analyzed. The dominant mechanisms of the charge–carrier transport through the diodes are determined. It is shown that the dominant mechanisms of the transport of charge carriers through the graphite/p-Si Schottky diodes at a forward bias are multi-step tunneling recombination and tunneling described by the Newman formula (at high bias voltages). At reverse biases, the dominant mechanisms of charge transport are the Frenkel–Poole emission and tunneling. It is shown that the graphite/p-SiC Schottky diodes can be used as detectors of ultraviolet radiation since they have the open-circuit voltage Voc = 1.84 V and the short-circuit current density Isc = 2.9 mA/cm2 under illumination from a DRL 250-3 mercury–quartz lamp located 3 cm from the sample.

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