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The paper analyzes the views of Prof. Ekaterina I. Kozlova concerning the lost values of the procedures institutionalizing the Russian Parliament, the risks of inconsistent implementation of mechanisms of recognition of powers of elected deputies of legislatures, peculiarities of procedures under consideration in other countries. The author has determined the mechanisms of ensuring legitimacy of power. The paper provides arguments in favour of preserving legal traditions, customs and rituals to ensure the stability of the constitutional order. The hypothesis has been put forward that constitutional identity and continuity of historical development are covered by the concept of constitutional continuity. It is concluded that the study of the constitutional continuum as a concept reflecting the natural relations between different conditions of the constitutional order can contribute to the ensuring of the legitimacy of the power and finding the best ways of transforming the constitutional and legal system.

The effect of irradiation by carbon ions in the mode of short-pulsed ion implantation on the optical and electrical characteristics of graphite-like pyrolytic boron nitride was studied. The characteristics of the states of growth defects localized in the band gap change more significantly with an increase in the energy density of the ion beam, which is accompanied by the ordering of the electronic structure of the compound due to radiation – thermal annealing. Absorption spectra indicate the predominant effect of static disorder due to defects. Irradiation forms a defective semiconductor material with a maximum band gap of 3.3–3.45 eV, a current value of 2.65–2.83 eV for direct transitions and 1.1–1.8 eV for indirect transitions, and an absorption edge due to exponentially distributed states of 1.3–2.6 eV and 2.6–3.3 eV defects of different nature. Anion vacancies, their clusters and impurity-vacancy complexes make the main contribution to the material properties. Irradiation forms low – conducting dielectric layers with surface conductivity of mixed n– and p–type on the surface of a pyrolytic boron nitride. The conduction mechanism is determined by the activation exchange of charge carriers between the allowed bands and donor and acceptor levels due to radiation and growth defects. After irradiation, the Fermi level remains localized near the position characteristic of the pyrolytic boron nitride near the middle of the band gap.

In this paper, we study the optical properties of aluminum- and silicon-nitride films and Al–Si–N coatings with variable atomic composition deposited by reactive magnetron sputtering on glass, silicon, and steel substrates. The absorption and luminescence characteristics are determined by the composition of the coatings and microstructure and depend on the physical properties of the substrate. The absorption and luminescence centers are associated with intrinsic defects in the nitrides and their simplest complexes. The relationships between the accumulation of growth defects, their interaction, the type of distribution of localized states, the band gap, and the stability of the optical properties are established. At an increase in the silicon content in the coatings, the degree of static induced disorder increases, and the contribution of the continuous distribution of the defect levels and interband absorption increases. Silicon-containing defects stabilize the optical properties of the coatings.

The energetic characteristics of growth and radiation defects (RDs) in boron carbide films deposited by reactive magnetron sputtering on a steel substrate and irradiated with powerful electron and pulsed ion beams were investigated. The relationship between the characteristics of point RDs, the degree of distortion of the electronic structure and the characteristics of interband and exponential absorption was established. The absorption spectra of the films were due to electronic transitions between the defects energy states localized in the band gap and interband transitions. The stability of characteristics to electron irradiation was due to the high concentration of growth defects, distributed along the boundaries between the structural fragments. Short-pulse implantation of carbon ions stimulates partial annealing of intrinsic RDs and their redistribution and formation of thermally stable complexes from defects. Boron carbide films significantly exceed the radiation resistance of sodium calciu...

In this paper the optical absorption characteristics of Al–Si–N coatings, deposited by magnetron sputtering on the substrates from silicon single crystals and glass were studied. The influence of conditions deposition on optical properties has been determined. The characteristics of interband and exponential absorption are determined by influence of localized states (LS) of defects continuously distributed in the band gap (BG) and reflect the influence on properties of crystalline and amorphous components material of coatings. The interband absorption is realized via the allowed indirect transitions through the optical gap 2.7–2.8 eV and direct transitions through the gap 3.8–3.96 eV. The interrelations between the parameters of interband and exponential absorption are typical for the naterials, whose properties are determined by a static and/or dynamic disordering of the crystal lattice by the defects of a different nature. Maximal average value of the BG width is 4.8–5.1 eV in the scope of semiclassical analysis applied to amorphous and strongly defective materials. The optical parameters of deposited coatings are changed in correlation with a changing of the mechanical characteristics in dependency on the nitrogen pressure.

The electrical and photoelectric properties of polycrystalline Si are studied after the high-intensity short-pulse implantation of C ions. It is established that annealing in vacuum (10–2 Pa, 300–1200 K) affects the characteristics of the surface dark conductivity and photoconductivity of Si. The optimal conditions for the thermal vacuum treatment of samples in the case when properties most stable to thermal effects and field excitement are reached are determined. The probable reasons for the change in the electrical and photoelectric characteristics of Si are established.

The article focuses on the investigation of the properties of alumina-zirconia ceramics possessing high mechanical characteristics and good conductivity at high temperatures. Measurement results of the dielectric dissipation factor, dielectric constant, electric conductivity when using direct and alternating current for the ceramics samples of 80%(ZrO2-3%Y2O3)-20% Al2O3 composition are presented in the paper. Measurements were conducted simultaneously in the electrostatic field in vacuum while heating the samples to the temperatures ranging from 300 to 1700K. Investigations showed that alumina-zirconia ceramics at high temperatures obtains ferroelectric properties not typical of these structures.

The electric and photoelectric properties of gallium-arsenide films deposited on a polycrystalline corundum substrate from the ablation plasma formed by a high-power ion beam are investigated. It is ascertained that vacuum and air annealing (in the former case, P = 10−2 Pa and T = 300–1200 K) and sulfide chemical passivation in an alcoholic solution affect the characteristics of the dark conductivity and photo-conductivity of the film surfaces. The optimal conditions for thermal and chemical treatment, at which the most stable changes in film the properties are attained, are determined. Enhancement in the stability of the electrical and photoelectric characteristics of films, which is achieved after thermal treatment, arises from the annealing of defects and their clusterization. Sulfide passivation leads to changes in the characteristics and increases the stability of properties under air oxidation.

Electrical and photoelectric properties of polycrystalline silicon after high-intensity short-pulse implantation of carbon ions have been studied. It has been found that vacuum annealing (10–2 Pa, 300–1200 K) of silicon affects the surface dark and photoconductivity. Optimal conditions of thermal vacuum treatment of silicon have been found that provide the most heat and field resistant changes in its properties. Probable causes for the changes in electric and photoelectric characteristics of the material have been revealed.

Optical reflectance and absorbance of gallium arsenide films formed on polycrystalline corundum, quartz glass, and copper foil are investigated in the energy interval of 1.1–6.2 eV. The films have been deposited from ablation plasma induced by a high-power ion beam. The exponential and interband absorbance spectra of the material of films are determined by defects in the GaAs crystalline lattice and the intricate composition of the material with predominance of nanocrystalline inclusions in the amorphous phase. Films deposited on polycor at the plasma flame center with the use of a low-resistance target have optimal properties for application in devices of optoelectronics and solar power engineering. Thermal vacuum treatment at 300–850 K modifies the optical properties of films owing to annealing of defects and changing of the structural-phase composition of a material.

The optical absorption of leucosapphire and polycrystalline corundum (polycor) upon coimplantation of iron and chromium ions and subsequent annealing in vacuum is studied. The structure of the states localized in the band gap induced by radiation defects exhibits a higher stability to annealing as compared to implantation of other types of ions into aluminum oxide and to separate irradiation with iron and chromium ions. The governing contribution to the exponential and interband absorption is made by substitutional defects of either type, their clusters, and impurity-vacancy complexes. The effect of incorporated iron ions on the population of levels of chromium-containing defect clusters, on their recharge, and on interaction with intrinsic radiation and biographical defects is revealed. Mixed clusters of substitutional defects are optically active in a spectral range of 2.0–4.0 eV after annealing at a temperature of 1300–1600 K.

Optical absorption of leucoosapphire and polycrystalline corund (polycor) is studied after irradiation with cobalt ions and subsequent annealing in a vacuum. The structure of states localized in the forbidden band and induced by various imperfections has a higher stability to annealing as compared to the case of implantation of other types of ions into aluminum oxide. The fan-like behavior of the dose-dependent absorption spectra is a consequence of the defect-induced disordering of crystal lattices. It is determined that intrinsic radiation-induced defects, substitutional defects, complexes containing them, and Co nanoparticles have an influence on the parameters of the focal point of the absorption spectra. The parameters of the interband and exponential absorption demonstrate the formation of a new multidefect material with a band gap width ranging from 5.3 to 5.5 eV and an absorption edge at 2.0–5.2 eV caused by the localized states of defect clusters.

The paper is focused on the study of the structural, electrical and optical characteristics of the ceramic silicon carbide before and after irradiation in the regimes of the high-power ion beams (HPIB) and high-intensity short-pulse implantation (HISPI) of carbon ions. The dominant mechanism of transport of charge carriers, their type and the energy spectrum of localized states (LS) of defects determining the properties of SiC were established. Electrical and optical characteristics of ceramic before and after irradiation are determined by the biographical and radiation defects whose band gap (BG) energy levels have a continuous energetic distribution. A dominant p-type activation component of conduction with participation of shallow acceptor levels 0.05-0.16 eV is complemented by hopping mechanism of conduction involving the defects LS with a density of 1.2T0{17}-2.4T0{18} eV{-}Am{-3} distributed near the Fermi level.The effect of radiation defects with deep levels in the BG on properties change dominates after HISPI. A new material with the changed electronic structure and properties is formed in the near surface layer of SiC after the impact of the HPIB.

The energy and kinetic characteristics of the dark conductivity and photoconductivity of polycrystalline alumina irradiated by titanium ions and then annealed in vacuum and air have been studied. The effect of temperature on the properties and electron-transport mechanisms is determined. In the air pressure range from 105 to 1 Pa, the electrophysical properties are reversible. A semiconductor coating can be formed on the alumina surface via vacuum annealing; when heated in air, it becomes insulating. The reverse transition is also possible. These modifications are related to the formation of defects, accumulation of oxygen-containing complexes, and changes in the stoichiometric compositions of the compounds synthesized by the ion thermal treatment.

We have studied the optical absorption in sapphire after Fe-ion irradiation and subsequent vacuum heat treatment. The absorption parameters and the nature of the transitions between localized states and allowed bands have been shown to be influenced by substitutional defects, intrinsic radiation-induced defects, and their complexes. We have evaluated the contributions of individual substitutional defects, their clusters, and complexes of substitutional defects with native vacancies and the effect of the iron oxides forming during annealing on the absorption in sapphire. The nature of the substitutional defect clusters and impurity-native defect complexes has been analyzed in detail.

Electrophysical properties of polycrystalline diamond films (PDF), deposited from the abnormal glow discharge, were obtained. The energetic and kinetic characteristics of surface dark and photoconductivity of PDF and their temperature, field and spectral dependences were investigated. Dominant carrier transport mechanisms, their type and the energetic spectrum of localized defect states were established. Current-voltage characteristics, photosensitivity and activation energy are determined by conductivity of PDF, which varies from 10{-14} to 10{-4} S depending on deposition conditions. Vacuum annealing of films up to 600-800 K stabilizes the electrical characteristics. Thermal stability of PDF properties higher than semiconductor films, deposited under nonequilibrium conditions by pulsed laser and ion ablation. PDF films not inferior on properties to films, obtained by alternative CVD methods. Electrical characteristics, mechanism of charge transport of PDF were caused by defects of different nature, the energetic levels of which are continuously distributed on energy in the band gap. Dominant n-type of activation conduction is complemented by hopping mechanism through the localized states distributed near the Fermi level with density 5.6x10{17}-2.1x10{21} eV{-1} cm{-3}. Trapping and recombination centers are heterogeneously distributed on grain boundaries.

The optical and electrophysical properties of polycrystalline diamond films (PDF) deposited from the abnormal glow discharge have been studied. The dominating mechanisms of absorption and charge carrier transfer and the energy spectrum of the localized states (LS) of defects which determine the properties of the films have been specified. The parameters of the interband absorption and electrical conductivity are determined by the continuous energy distribution in the band gap (BG) of the states of defects of different nature. The absorption edge of the crystalline phase of the films is separated from the absorption zone determined by the electron transitions between LS defects. The width of BG is narrowed to 0.2-0.5 eV from the quantity typical to the diamond. An additional film absorption edge is formed in the energy interval 1.2-3.3 eV, where Urbach rule is fulfilled and the interband absorption is realized at direct transitions through the optical gap 1.1-1.5 eV. The average width of BG is 2.6-3.24 eV estimated within semiclassical interband model. The interaction of the parameters of the interband and exponential absorption is determined by the crystal lattice static disorder. The dominating n-type of the activation component of the electrical conductivity is complemented by the hopping mechanism with the participation of the localized states of the defects distributed near the Fermi level with a density 5.6•10{17}-2.1•10{21} eV{-1}•cm{-3}.

Concentration depth profiles of implanted impurities and surface microstructure of modified polycrystalline α-Al 2 O 3 were studied in the vicinity of the post-implantation annealing temperature of 1380 °C where a transition to low-resistance state occurs. The modification procedure was Ti ion implantation with simultaneous deposition of W (IBAD) and subsequent isochronal annealing in vacuum at temperatures ranging from 900 to 1500 °C. Direct metal vapor vacuum arc pulsed implantation of Ti ions (50–150 keV, 10 17 ions per cm 2 , RT) was used. This treatment of ceramics is of interest for both basic and applied research. On the scientific side, it is intended to elucidate the correlation between the physical properties of ceramics and their nanostructure. From the point of view of the applications, this treatment is promising for production of low-cost, high ohmic thin film resistors and advanced gradient thermally stable metal/ceramic interfaces. Rutherford backscattering spectrometry (RBS) of 4 He + ions with initial energy of 1.8 MeV was used to determine the concentration depth profiles of the implanted impurity in the Al 2 O 3 matrix. Scanning electron microscopy was applied to surface microstructure studies of the ceramics. RBS spectra were measured from the alumina samples annealed at temperatures corresponding to the maximum of the sheet resistivity–annealing temperature curve. The effective diffusion coefficient of implanted Ti in Al 2 O 3 was found to be 2.43×10 −14 cm 2 s −1 for a temperature range of 1150–1230 °C. Nanocrystalline grains with a typical diameter of approximately 40–50 nm were formed at all post-implantation annealing temperatures. These nanocrystallites agglomerate into larger particles, the latter forming a quasi-crystalline surface structure at approximately 1150 °C. The transition to the low resistance electric state in Al 2 O 3 at the post-implantation annealing temperature of approximately 1380 °C occurs simultaneously with a redistribution of the implanted Ti ions towards the near-surface layer and with a formation of a 2D honeycomb (average structure unit is 330 nm in length) nanostructure like an infinite cluster. The grain growth depression observed at temperatures near or above 1150 °C is consistent with the assumption that a diffusion barrier of the W and Ti constituents is formed on the nanocrystallite surfaces.

The parameters of the induced and biographical defects and their complexes in nitride ceramics, in single and in polycrystalline aluminium oxide after ion irradiation and following thermal annealing are studied. An influence of the defects on the charge transport and recombination process and on the optical absorption and photoconduction is determined. General characteristics of defect formation in dielectrics having a different structure and band gap width were established. The localized states of defects are combined into a subband within the band gap as a result of the accumulation and interaction of the induced defects. The charge transport occurs by hopping mechanism within the donor subband and in part by activation mechanism. The largest change of conduction and optical properties is accompanied with Fermi level shift to the conduction band.

The parameters of defects of radiation-induced and biographic types and of their complexes in boron nitride andAl 2O3 mono- and polycrystals after ion and thermal modification are investigated invoking the methods of optical and thermoactivation spectroscopy. The influence of electron transitions involving defect energy levels on changes in the electrophysical and optical properties of modified dielectrics is recognized. The contribution of the forbidden band width and of the material structure to changes in the properties of defect clusters with continuous spectra of energy levels and of separate radiation-induced point-type defects with local energy levels is evaluated. The stability of defects with various energy spectra under thermal, field, and photoexcitation and also after heat treatment in air is evaluated. The most probable nature of vacancy and impurity-vacancy defects and of vacancy complexes is understood.

The characteristics of interband and exponential optical absorption of leucosapphire and polycrystalline corundum (polycor) after irradiation with chromium ions and subsequent annealing in vacuum at 300-1800 K and in air at 300-800 K are studied. Contributions of defects with different thermal and chemical stability into optical parameters were established. The effect of intrinsic radiation defects, of substitutional defects and of complexes on base of oxygen and defects on formation the focal point in absorption spectra owing to fulfilment of the Urbach rule was determined. Heating in air of strongly defective material synthesized in surface layers of alumina by the ion-heat modification influences the characteristics of defects and the electronic structure of band gap negligibly.

Electrical and photovoltaic properties of polycrystalline diamond films (PDF), deposited from the abnormal glow discharge were analysed. Features of charge carrier transfer in PDF are determined by continuous energy distribution in the band gap of defect states of different nature. Dominated n-type conductivity activation component of electrical conduction and photoconductivity is complemented by a hopping mechanism with the participation of states near the Fermi level with a density 5.61017–2.11021 eV−1 cm−3. Activation transfer is realized in the exchange of charge carriers between the allowed bands and donor levels with the activation energy 0.007-0.21 eV, which are sparsely populated and have wide variation in their parameters. Trapping centers and carriers recombination are heterogeneously distributed in grain boundaries. Under lighting, the state density increases 3-5 times and probable jump length decreases by 1-3 nm. Spectral distribution centers of photosensitivity are correlated with the distribution of deep-level defects, determining the absorption spectra.

Electrophysical and photoelectric properties of thin GaAs films deposited on polysilicon by pulse ion ablation using high-power ion beams have been investigated. The predominant charge carriers transfer mechanism in films and the type of dark and photoconductivity have been established. A vacuum annealing effect (10−2 Pa, 300-1000 K) on energetic and kinetic characteristics of dark and photoconductivity, the transfer mechanism and the type of charge carriers have been determined. The most probable causes of changes in the film electric and photoelectric characteristics have been discussed.

Based on the analysis of the experimental behavior of the conductivity of highly dispersed aluminum nitride ceramics on temperature and frequency, conclusions are drawn about the existence in polycrystalline AIN of electromigration hopping mechanisms. At low temperatures and for high frequencies, the conductivity can be described within the framework of a two-point model, but as the temperature increases, or as the frequency decreases, a transition is observed through multiple jumps. The electromigration activation mechanisms dominate at temperatures higher than 370 K.

Investigations are made of the structural parameters and temperature dependences of dielectric properties of aluminium nitride ceramics synthesized, by various methods using powders with sintering-assisted additives. The separation of resistivities and capacitances of structural fragments and their interfaces, using the Coule diagrams, allows to assume a preferential influence of the boundaries on the charge carrier transport and dielectric properties. The detailed investigations of the structural parameters of the ceramics made it possible to propose a block model of its building: a fragment of size dr which is free of macrodefects; the d-size crystallite consisting of dr regions divided by dislocations and/or stacking faults, and the crystallite aggregate of size D. All the impurity phases are involved in the aggregate interfaces. The analysis of the results shows that the ceramic conductivity is generally determined by the sizes dr and d rather than D. Impurity phases are found to have a weak influence on the electric conductivity in the region of the intrinsic charge carrier transport, especially at T > 600 K. Es werden die Strukturparameter und Temperaturabhangigkeiten der dielektrischen Eigenschaften von Aluminiumnitridkeramik untersucht, die mit verschiedenen Methoden aus Pulvern mit Sinterzusatzen synthetisiert wird. Die Trennung der Widerstande und Kapazitaten der Strukturfragmente und ihrer Grenzflachen mit Hilfe der Coule-Diagramme erlaubt, einen bevorzugten Einflus der Grenzen auf den Ladungstragertransport und die dielektrischen Eigenschaften anzunehmen. Die ausfuhrlichen Untersuchungen der Strukturparameter der Keramik ermoglichen die Aufstellung eines Blockmodells und dessen Aufbau: ein Fragment von der Abmessung dr, das frei von Makrodefekten ist; der Kristallit von der Grose d bestehend aus dr-Bereichen, die durch Versetzungen und/oder Stapelfehlern getrennt sind, und Kristallitaggregate von der Grose D. Alle gestorten Phasen sind an den Aggregatgrenzflachen beteiligt. Eine Analyse der Ergebnisse der Untersuchungen zeigt, das die Keramikleitfahigkeit im allgemeinen durch die Abmessungen dr und d und weniger durch D bestimmt sind. Es wird gefunden, das die gestorten Phasen einen geringen Einflus auf die elektrische Leitfahigikeit besonders im Bereich des intrinsischen Ladungstragertransports bei T > 600 K haben.