The results of studying the quantum conductance staircase of holes in one−dimensional channels obtained by the split−gate method inside silicon nanosandwiches that are the ultra−narrow quantum well confined by the delta barriers heavily doped with boron on the n−type Si (100) surface are reported. Since the silicon quantum wells studied are ultra−narrow (~2 nm) and confined by the delta barriers that consist of the negative−U dipole boron centers, the quantized conductance of one−dimensional channels is observed at relatively high temperatures (T > 77 K). Further, the current−voltage characteristic of the quantum conductance staircase is studied in relation to the kinetic energy of holes and their sheet density in the quantum wells. The results show that the quantum conductance staircase of holes in p−Si quantum wires is caused by independent contributions of the one−dimensional (1D) subbands of the heavy and light holes; these contributions manifest themselves in the study of square−section quantum wires in the doubling of the quantum−step height (G₀ = 4e²/h), except for the first step (G₀ = 2e2/h) due to the absence of degeneracy of the lower 1D subband. An analysis of the heights of the first and second quantum steps indicates that there is a spontaneous spin polarization of the heavy and light holes, which emphasizes the very important role of exchange interaction in the processes of 1D transport of individual charge carriers. In addition, the field−related inhibition of the quantum conductance staircase is demonstrated in the situation when the energy of the field−induced heating of the carriers become comparable to the energy gap between the 1D subbands. The use of the split−gate method made it possible to detect the effect of a drastic increase in the height of the quantum conductance steps when the kinetic energy of holes is increased; this effect is most profound for quantum wires of finite length, which are not described under conditions of a quantum point contact. In the concluding section of this paper we present the findings for the quantum conductance staircase of holes that is caused by the edge channels in the silicon nanosandwiches prepared within frameworks of the Hall. This longitudinal quantum conductance staircase, G_xx, is revealed by the voltage applied to the Hall contacts, V_xy, to a maximum of 4e²/h. In addition to the standard plateau, 2e²/h, the variations of the V_xy voltage appear to exhibit the fractional forms of the quantum conductance staircase with the plateaus and steps that bring into correlation respectively with the odd and even fractional values.

The article is devoted to the current state and prospects of production development of main material — polycrystalline silicon (polysilicon) which is used in the manufacture of products for micro and power electronics and photovoltaics. The article includes polycrystalline silicon market dynamics analysis. It is noted that the increase in polysilicon output is primarily connected to the growing needs of photovoltaics and the global trend of transition to renewable, alternative energy. It is assumed that the annual increase in the output of polysilicon will reach a level of 10−15 % or more. There are several facts that are important for the intensive development of photovoltaics. They include level of polycrystalline silicon technology and the availability of this material for large−scale production of highly efficient solar cells. According to forecasts, the main technology used in the industry based on «Siemens Process» will remain dominant in the foreseeable period of time. LLC «Kremniytehnoprom» is developing a modern polysilicon production project based on the original designs and modernization of «Siemens Process». It is planned to be created in Russia with the involvement of leading German specialists and enterprises (SPSC GmbH, GEC GmbH). The project provides maximum safety of production, despite the potential risks inherent in technology. First of all it is ensured by guarantees of hardware−technological schemes performance, reliability of the equipment and design solutions in general, as well as by a set of emergency protections. Toxic production waste will be processed into safe substances — targeted products for sale. The created enterprise will ensure the optimization of key indicators for competitive production: the price of polysilicon, production volumes, specific capital investments and current unit costs.

Lithium niobate films on silicon substrates were synthesized by high−frequency magnetron sputtering of a target. The resultant film was a layer of polycrystalline lithium niobate. By the method of spectrophotometry we obtained the spectral dependences of the reflectance in the wavelength range 300—700 nm at small angles of incidence. The angular dependence of p− and s− polarized light were measured for a discrete set of wavelengths from 300 to 700 nm increments of wavelength 50 nm and increments for angles of 1°. The values of the refractive indicies, film thickness and extinction coefficients were determined using a numerical method for solving inverse problems. As the film is absorbing we accepted the simulation optical system as an isotropic monolayer absorbing film on a semi-infinite absorbing substrate with a sharp interface. Initial approximation for the solution of inverse problems were defined by the methods based on the estimation of the interference extrema position in the reflection-angular spectra. Values of the refractive indicies of the film differ from the values typical for LiNbO3 single crystals obtained both from the reference literature, and by refractive indices direct goniometric method measurements of a certified standard enterprise sample (SES) made from a lithium niobate single crystal. We additionally studied the specimens with X−ray diffraction and scanning probe microscopy. These deviations are attributed to the film inhomogeneity, the presence of the second phase, and disordering of the structure. Inclusions of the second phase in the form of crystallites with a predominant orientation along the Z axis are observed.

Solid−state lighting technology based on LEDs offers ample opportunities in plant lighting. This article presents a prototype of a solid−state lamp based on InGaN LEDs with radiation peaks of 440, 460, 530 and AlInGaP with radiation peaks at 590, 630 and 660 nm, equipped with a source of stabilized current and an optimized radiator. The emission spectrum of the LED illuminator is the result of numerical simulation using an experimentally obtained absorption spectrum of a leaf of a plant. The effect of using LEDs was compared to the effect of a sodium tubular lamp. Evaluation of the results of biometric measurements that were made throughout the experiment showed the possibility of the effect of the spectrum of the proposed LED illuminator on plant growth.

The distribution of potential and parameters of potential barrier in semiconductor crystallite was calculated numerically. The calculation was carried out in spherical crystallite with evenly distributed donors and surface states. The calculation assumed that the surface charge is screened by both ionized donors and free electrons, the contribution of which cannot be neglected in semiconductors with high concentration of free electrons. The height of potential barrier is shown to nonmonotonically depend on the concentration of donors. The dependence of height of potential barrier on the concentration of donors may be divided into two part. One part of dependence describes the fully depleted crystallite and the second part describes the party depleted crystallite. On the first part the height of potential barrier increases with the donor concentration but on the second part the height of potential barrier decreases. The height of the potential barrier increases with increasing of concentration of surface states. The possibility of existing of potential barriers is estimated in nano− and polycrystalline metal oxide semiconductors used as sensitive layers of gas sensors. It is concluded that if the radius of crystal grains in metal oxide semiconductors does not exceed 10 nm, the explanation of the sensitivity of the sensor to gas by using a commonly barrier model seems unlikely. It is demonstrated that shape of crystallite and the contribution of free electrons to screening of surface charge have to be taken into account to calculation of width of potential barrier.

Dynamics of changes in fluorine atoms distribution through grown anodic oxide layer thickness and the effective surface charge on InAs crystals under such layers has been studied. Anodic oxidation was performed in alkaline electrolyte with fluorochemical additive component in galvanostatic mode at anode current densities 0.05 or 0.5 mA·cm⁻². The layers thickness in boundes 32—51 nm varied by electrodes final voltage setting in range 15—25 V. The layer thickness and refractive index was measured by ellipsometric method, and distribution of fluorine atoms through thickness — by photoelectron−spectroscopy method, combined with ion etching. At the same time, based on grown layers there were produced MIS structures, and from calculation of theirs capacitance−voltage characteristics are determined effective surface charge and surface states density, corresponding to different layer thicknesses.

Main results are reduced to the facts during layers growing despite of anodizing current density comes their sealing, the profile of fluorine atoms distribution shifts towards InAs, positive effective surface charge gradually decreases from 3.6 · 10¹¹ to 2.0 · 10¹¹ cm⁻² at surface states density in (6—7) · 1011 eV·cm⁻² range for all cases. Based on comparison of these data and theoretical concepts of MIS structure charge construction, there was made a conclusion about gradual built−in charge distancing from the border with InAs in the process of growing anodic oxide layer, which explains observed effective surface charge decrease during layer thickness increasing. This results indicates that the layer growth rate exceeds the built−in charge displacement rate towards InAs.

The vapor phase growth of Cd₃As₂—Zn₃As₂ (in the following (Cd_1−x Zn_x)₃As₂ solid solutions process is described. The (Cd_0,993 Zn_0,007)₃As₂ solid solution single crystals were synthesized. Scanning electron microscopy and electron diffraction data suggest high crystalline quality of studied sample. Its structure and surface morphology, indicating the presence of growth nuclei and cleavage planes, were investigated. Giant anisotropic magnetoresistance and Shubnikov — de Haas oscillations were observed at low temperatures. Obtained results suggests that peculiarities of Dirac semimetal phase persist in (Cd_1−x Zn_x)₃As₂ solid solution at low zinc content. At the same time, there are indications of some differences with initial Cd₃As₂ properties.

The effect of photon annealing on the occurrence of deformations in the crystal structure of boron−doped silicon wafers produced by the Czochralski (Cz−Si) was studied by the method of triple−X−ray diffraction. It was found that the traditional annealing of silicon wafers with polished surfaces on both sides by halogen lamps in Photonic Annealing (PA) and rapid thermal annealing modes (RTA) leads to compression deformation. The same process with the use of original photo− mask, which allows local processing produces multiple, spatially separated regions of the plate produced by Lосаl Photonic Annealing (LPA) at relatively low temperatures (less than 55 °C), gives rise to a tensile strain. This established effect is not observed if on the back side of the plates there is mechanical gettering layer. The mechanism explaining the experimental results can be used in the formation of the charge pump in the structure of the photo electric converters (PEC).