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The paper studies the gettering properties of nickel clusters in the silicon lattice. The gettering properties of nickel clusters were studied in various states, i.e., in original (reference) samples, as well as in samples with additionally doped interstitial and lattice site impurity atoms of sulfur and manganese. The electrophysical and photoelectric parameters were studied using modern instrumentation: INFRAM-I-type infrared microscope, IKS-21 and scanning electron microscope SEM (Oxford Instruments ZEISS EVOMA10), IKS-21. A new technology has also been proposed that makes it possible to getter harmful impurities; it is recommended for widespread use in the electronics industry and scientific research institutes for the production of materials with stable parameters and the development of fundamentally new devices. [ABSTRACT FROM AUTHOR]

In this paper, the effect of doping silicon with dysprosium (Dy) on its structural and optical characteristics is investigated. Silicon n-Si was doped with dysprosium by thermal diffusion at 1473 K for 50 h. Raman spectroscopy and X-ray diffraction analysis were used for the analysis. The Raman spectroscopy results showed a main peak at 523.93 cm-1, corresponding to n-Si optical phonons, with an increase in the intensity and full width at half maximum (FWHM) in n-Si samples, indicating an improvement in the crystallinity of the structure. A decrease in the intensity of the peaks at 127.16 cm-1 and 196.24 cm-1, associated with amorphous structures, confirms a decrease in defects. The detection of a new peak at 307.94 cm-1 indicates successful deposition of dysprosium as nanocrystallites associated with the 2TA phonon mode in the cubic phase of Dy2O3. X-ray diffraction analysis revealed characteristic structural lines indicating the (111) crystalline orientation and the presence of microdistortions in the lattice. Heat treatment and rapid cooling lead to a change in the intensity of structural lines, an increase in the second- and third-order lines, which indicates microstrains and a change in the size of subcrystallites. Doping of silicon with dysprosium improves the crystallinity of the structure, reduces the number of defects and forms polycrystalline layers on the surface consisting of SiO2 and Dy2O3 nanocrystals. [ABSTRACT FROM AUTHOR]

The characteristics of silicon MIS structures with ytterbium impurity are studied using non-stationary capacitance spectroscopy of deep levels. It is established that the presence of ytterbium atoms in the bulk of the silicon substrate leads to a shift in the capacitance-voltage characteristics towards positive bias voltages and a decrease in the density Nss of the surface states of the MIS structures. It is shown that this effect depends on the concentration of ytterbium atoms in the silicon substrate of the studied structures. In MIS structures based on Si, one deep level with an ionization energy Ec-0.32 eV is detected. [ABSTRACT FROM AUTHOR]

In this work, the electrical and photoelectric properties of the near-surface and surface layers of silicon doped by diffusion with chromium atoms were investigated. The formation of an anomalous concentration of charge carriers in these regions, as well as an anomalously low mobility, was revealed. The specific conductivity of the near-surface layer with a thickness of 1÷5 μm turned out to be equal to (1.6÷9.9)·10³ Ohm-1·cm-1. The inhomogeneity of the crystal under study was determined by the light probe method. [ABSTRACT FROM AUTHOR]

The paper investigates the photovoltaic properties of the silicon n+-p-p+-structures and photodiodes made on their basis. It was found that boron diffusion to the reverse side of the substrate, in addition to creating an ohmic contact, generates generation-recombination centers, which allows to reduce the dark current of photodiodes and increase their responsivity. It was also found that chemical dynamic polishing of the back side of the substrates before boron diffusion allows to eliminate a significant number of defects and improve the final parameters of the products. In samples without a p+-layer and samples not polished from the back side, a breakdown of the p-n junction is observed on the back side, which is caused by the expansion of the space charge region to the entire thickness of the substrate and the achievement of a defective back side of the crystal. [ABSTRACT FROM AUTHOR]

In this work, new sensitive thermal sensors based on Si and Si were developed. Single-crystal n- and p-type silicon samples doped with phosphorus and boron during growth were used for the study. These samples were first doped with platinum and palladium, then subjected to ohmic contact with nickel. To manufacture temperature sensors based on n-Si˂Pd˃ and obtain an ohmic contact, this material was subjected to appropriate mechanical and chemical treatments. Metallic nickel with a thickness d = 1 μm was chemically deposited on its surface, followed by thermal annealing in a vacuum at T = 400-450℃ for t = 10 - 15 minutes. To compare the created temperature sensors, a special measuring device, a thermostat, was developed to ensure uniform heat transfer. [ABSTRACT FROM AUTHOR]

The paper proposes the technology of silicon p-i-n mesa-photodiodes, which allows to exclude one high-temperature operation from the technological route. Reducing the number of thermal operations reduces the degree of degradation of the electro-physical characteristics of silicon during heat treatment, which also contributes to reducing the density of surface states at the SiSiO2 interface. It is proposed to etch the mesa-profile by the method of chemical-dynamic polishing using a gold masking coating. The obtained photodiodes are cheaper than serial samples made by diffusion-planar technology and have higher sensitivity. [ABSTRACT FROM AUTHOR]

This article presents the gettering mechanism and the physical model of impurity Ni atom clusters in the Si crystal lattice. The study finds out that the formed Ni atom clusters lead to gettering various rapidly diffusing impurities, both present in the Si lattice and introduced, as well as oxygen atoms, by stimulating generation of recombination centers of thermal and radiation defects. [ABSTRACT FROM AUTHOR]

This study defines the technological procedures for obtaining GexSi1 – x alloys through the diffusion method by introducing germanium atoms into monocrystalline silicon. The research results indicate that the fundamental parameters of the resultingGexSi1 – x alloys differ from the fundamental parameters of the initial silicon, particularly altering the energy values of silicon's forbidden zone. Elemental analysis of the sample surfaces revealed silicon concentration (in atomic percentages) of approximately ~ 70.66 % and germanium ~29.36%. To manufacture and study the parameters of silicon-based solar cells with GexSi1 – x–Si heterostructures, we used samples obtained by two different methods. In the first method, the p-n junction was formed by introducing phosphorus impurity atoms into the original silicon of p-type silicon grade. In the second method, the p-n junction was formed by boron diffusion into the original silicon of SEPH (silicon electronic type, doping material of phosphorus) grade. In both cases, the depth of the p-n junction ranged from 0.5 to 6 μm. It was also shown that the binary compounds GexSi1 – x are a new material for modern electronics; the possibility of creating properties in electronics based on them was shown. Based on them, it is proposed to create devices and new functionality and highly efficient solar cells. [ABSTRACT FROM AUTHOR]

The paper describes the research and study of the process of electrically induced diffusion of Mn atoms in silicon directly from a Si surface layer that was preliminarily enriched with Mn. To ensure the so-called electrically induced diffusion process, a constant electric field was applied to the investigated samples. It has been revealed that as a result of the diffusion of Mn impurity atoms into samples placed at the negative pole of the electrical diffusion unit, the proportion of Mn atoms was 75.4% (relative to silicon atoms), while in samples placed at the positive pole this indicator tended to be 2.7% (relative to silicon atoms). Besides that, for the first time, an experimental increase in the electro-active concentration of Mn impurity atoms in silicon (at T = 900°C) was detected under the influence of an external constant-value electric field. In this case, the maximum solubility of impurity atoms of Mn at a temperature of T = 900°C was NMn~2.27·1014 cm-3, while the average concentration of electro-active Mn atoms diffused into silicon under the influence of an external constant electric field reached NMn*~2.62·1014 cm-3. [ABSTRACT FROM AUTHOR]

In this work, the influence of alpha particles, protons and gamma rays on the crystal structure and structural characteristics of n-type silicon (n-Si) single crystals was studied using X-ray diffraction. N-type silicon (KEF-40) was used for the study. The samples were irradiated with protons with a dose of 9×1014 cm-2 with an energy of 600 keV and a current of 1÷1.5 μA, irradiated with alpha particles with a dose of 6×1014 cm-2 with an energy of 800 keV and a current of 0.5÷1 μA and γ-60Co quanta with a flux intensity of ~ 3.2×1012 quantum/cm2·s. Based on the results of X-ray diffraction analysis, it was established that distortions, vacancies and amorphization of lattice parameters that arose after irradiation lead to an increase in lattice parameters. [ABSTRACT FROM AUTHOR]

In this work the mechanism of current flow during illumination with hν≥Eg in the temperature range of 77÷300 K is considered. It is established that in the PtSi - Si-M structure in the temperature range of 77÷270 K the regime of space charge limited currents (SCLC) is realized. The current-voltage characteristics of the structures show areas of linear and quadratic dependences of current on voltage, as well as areas of a sharp increase in current. These features of the current-voltage characteristic are explained by the presence of deep level structures and sticking levels for charge carriers in the base region. From the temperature dependence of the SCLC, the concentration of adhesion levels was determined to be equal to (1.8÷3) 1015 cm-3 and the adhesion factor to be equal to 6.32·10-2. In the temperature range 77÷115 K at voltages 0.2÷1 V, the current-voltage characteristic obeys the law J ~ Un(n=3÷4), and above U - the law J ~ U6, followed by a transition to the quadratic law. [ABSTRACT FROM AUTHOR]

In this work, samples of single-crystalline silicon doped with tin were studied using X-ray diffraction and electron microscopy. It has been established that at a scattering angle of 2θ ≈ 36.6° in the X-ray diffraction patterns of n-Si and Si samples, structural reflections (110) of the corresponding SiO2 nanocrystallites with lattice parameters a = b = 0,4936 нм и c = 0,5212 nm and c = 0.5212 nm, belonging to the hexagonal crystal lattice and space group P321. The formation of tin nanocrystallites with sizes of 9.1 and 8 nm in the near-surface regions of the Si matrix crystal lattice was discovered. [ABSTRACT FROM AUTHOR]

The article examines the influence of structural defects, in particular dislocations, on the electrical and photovoltaic properties of silicon four-quadrant p-i-n photodiodes. It was established that growth defects and defects formed during mechanical processing of plates can cross the entire substrate and deteriorate the parameters of photodiodes. This phenomenon is particularly negative due to the placement of defects in the space charge region. In this case, due to the presence of recombination centers in the space charge region, the life time of minor charge carriers decreases and the dark current and responsivity of photodiodes deteriorate. Often, the placement of defects is uneven, which provokes unevenness of parameters on responsive elements. It was also seen that the dislocation lines crossing the responsive elements and the guard ring worsen the insulation resistance of the specified active elements. A method of determining the final resistivity of silicon and the diffusion length of minor charge carriers by studying the pulse shape of the output signal is proposed. [ABSTRACT FROM AUTHOR]

In this research, a comprehensive study of the effect of doping silicon with gold on the optical properties and morphology of silicon layers was carried out. For this purpose, the methods of Raman spectroscopy, Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM) were used. The results of the study showed that the transition from original silicon to gold-doped silicon leads to significant changes in the optical properties and morphology of the layers. Raman spectra showed characteristic peaks in the regions of 144, 304, 402, 464, 522, 948 and 973 cm-1, associated with the violation of long-range order of the crystal lattice and the interaction of gold with silicon. The intensity and position of the peaks in the spectra allowed us to draw conclusions about structural changes, including a decrease in crystallinity and the formation of amorphous and nanocrystalline structures in the samples after treatment at 1373 K. New peaks in the Raman spectra associated with Au-Au stretching and the formation of new bonds Si-Au, confirm the processes in silicon layers when alloyed with gold. SEM studies provided information on the structure, chemical composition and arrangement of n-Si-Au and p-Si-Au samples. The spherical arrangement of gold atoms on the surface of single-crystalline silicon was experimentally established, which indicates the diffusion of gold and the formation of gold silicate, which introduces a positive charge to the interface. Morphological changes included an increase in the number of agglomerates with nanocrystals smaller than 7-9 nm and an increase in the transparency of the layer. These results indicate the possibility of improving the photosensitivity of heterostructures with a Si-Au composite layer due to the quantum-size and plasmonic effects of inclusions containing silicon and gold nanoparticles. [ABSTRACT FROM AUTHOR]

In this paper, using a scanning electron microscope (SEM) and atomic analysis, the location map of microcomposites formed on the surface of n-Si, p-Si, n-Si and p-Si samples was studied. Force microscope (AFM) research devices. The atomic fractions of inclusions of carbon, oxygen and lutetium formed on the surface of the samples were studied. Also, using the ASM device, the sizes, relief and topographic appearance of defects formed on the surface of the samples were determined. In silicon samples doped with Lu, a decrease in the size of surface defects and the formation of nano-sized structures were found, which makes it possible to obtain materials with a more perfect crystal structure. Using a ZEISS GeminiSEM 300 scanning electron microscope, the structural structure, chemical composition and images of their arrangement of n-Si, p-Si, n-Si and p-Si samples were obtained. In this case, the electron accelerating voltage was 20 kV, and the pressure in the sample chamber was (10-3 mmHg). Research results show that the structural structure of microand nanocomposites formed in silicon mainly depends on the diffusion time and cooling rate of the samples after diffusion annealing. [ABSTRACT FROM AUTHOR]

The study of thin-film nanocomposites, including crystalline and amorphous silicon nanoparticles embedded in silicon oxide layers, is a key direction in the field of materials for optoelectronics. This study explored the interest in such composites, including erbium silicide (ErSi2-x), in the context of their applications in non-volatile memory and photovoltaic devices. Particular attention was paid to the structure and properties of such materials, including the analysis of defects in erbium-doped silicon. The results of the study, based on Raman spectroscopy and X-ray phase analysis, made it possible to identify the characteristics of the composition and structure of the studied samples. The identified data confirmed the presence of crystalline phases of Si and Er in the p-Si-Er composite, and also showed the substitution of Er in the p-Si/SiO2 structure. Additionally, X-ray microanalysis data confirmed the presence of Si, O and Er in the expected concentrations in the composite film. Further research showed that the introduction of erbium atoms onto the silicon surface leads to minor changes in some signals and the appearance of new vibrations in the Raman spectra of the samples. The decrease in the intensity of the peaks belonging to silicon is associated with the weakening and breaking of some bonds in the structure of the silicon crystal lattice and due to the formation of new bonds in which erbium atoms participate. Thus, the results of this study represent a significant contribution to the understanding of the properties and potential of thin film nanocomposites for applications in optoelectronics, and also enrich our knowledge of the effect of doping on the structure and properties of silicon materials. [ABSTRACT FROM AUTHOR]

In this work, the structural and optical characteristics of silicon (n-Si) samples and its compositions with dysprosium (n-Si-Dy) were analyzed using Fourier transform infrared spectroscopy (FTIR) and Raman spectroscopy methods. Characteristic peaks in the FTIR spectra such as 640 cm-1 (Si-H mode) and 1615 cm-1 (perpendicular stretching mode) were identified, indicating the structural features of the material. The appearance of additional peaks in the n-Si-Dy spectra at 516.71 cm-1 and 805 cm-1 indicates the influence of dysprosium on the structure and defectiveness of the material. Examination of the frequency range (1950-2250 cm-1) further confirms local vibration modes associated with defects and interactions with dysprosium. Peaks associated with Dy-Dy stretching, as well as interaction with silicon, were found at 2110 cm-1 and 2124 cm-1. Analysis of Raman spectra indicates the formation of silicon nanocrystals during annealing, which is confirmed by XRD results. The results obtained provide important insight into the effect of dysprosium on the structure and properties of silicon materials, which could potentially find application in optoelectronics and materials science. [ABSTRACT FROM AUTHOR]

Each crystal structure has its own phonon modes, which appear in the Raman spectrum of Raman scattering. In the case of silicon, phonon modes associated with the diamond structure of silicon can be detected. In a Raman spectrum, the position of the lines, their intensity, and the width of the lines are usually measured. Raman spectroscopy is a powerful tool for studying crystalline materials at the molecular level, and its application in the study of semiconductors and nanomaterials provides important information about their structure and properties. In this study, the spectra of two types of silicon were analyzed: n-Si and p-Si, as well as their doped analogues n-Si and p-Si. The obtained Raman imaging results demonstrated spatially varying nanocrystallinity and microcrystallinity of the samples. The n-Si and p-Si spectra indicate the appearance of a Raman band at 525 cm-1 with a shift of -5 cm-1 and +5 cm-1, respectively, relative to the position of the silicon substrate peak, indicating the presence of tensile strain in the materials. The absence of other impurity peaks indicates the high purity of the n-Si and p-Si samples. The holmium doped Si material exhibits additional peaks in the Raman spectra, which is attributed to the presence of vacancies and defects in the newly formed Si-Ho compositions. The results of the analysis of the spectra indicate the influence of doping silicon with holmium on its structure and properties, forming new bonds and defects. [ABSTRACT FROM AUTHOR]

The adsorption of the C60 fullerene molecule has been studied in various configurations on a reconstructed Si(100) silicon surface. Among fullerenes, fullerene C60 is of particular importance, since it has the most stable form and consists of 60 carbon atoms. Monocrystalline silicon has the diamond structure, the size of its crystal lattice is 5.43 Å. The MD-simulation calculations have been performed using the open source LAMMPS MD-simulator software package and the Nanotube Modeler computer program. The Tersoff interatomic potential has been used to determine the interactions between the Si-Si, C-C and Si-C atoms. The adsorption energy of the C60 molecule on the reconstructed Si(100) surface, the bond lengths and the number of bonds formed depend on the adsorption geometry, i.e. at what point on the substrate the molecule is adsorbed and in what configuration. [ABSTRACT FROM AUTHOR]

Experimental studies on the nature of chemical bonding in manganese silicate systems were carried out in photoelectron spectrometer ES-2402. It was established that the change in the binding energy of the core electronic levels of the atoms of the elements is subject to the general patterns of changes in the electronic structure and chemical characteristics within the Periodic System of elements. Additional data on the chemical bond energy of silicon in complex compounds of MnO–SiO2 and MnO–CaO–SiO2 were obtained. [ABSTRACT FROM AUTHOR]

In this work, the bandgap energy of Si samples doped with impurity atoms of elements Ga (AIII) and Sb (BV) by the diffusion method and without impurity atoms was studied. It is known that the bandgap energies of GaSb and Si semiconductors at room temperature are 0.726 and 1.12 eV, respectively. According to the results of the study, it was found that the band gap energies of Ga and Sb-doped and non-doped Si samples are 1.114 and 1.119 eV, respectively. When the samples were further annealed at a temperature of 600 °C, it was observed that the bandgap energy of the samples doped with Ga and Sb decreased to 1.10 eV. [ABSTRACT FROM AUTHOR]

In this paper, the electrical properties different diodes were reported. Pure and Al-doped ZnO thin films of different concentrations (Al: 1, 2 and 3 wt.%) were deposited by sol-gel dip-coating onto p-Si substrate to form heterojunctions. Zinc acetate dehydrate, Hexahydrate aluminum chloride, ethanol and ethanolamine were used as a starting material, doping, solvent and stabilizer, respectively. The dip-coating process with drying was repeated 6 times to obtain multilayer films. The morphological and electrical properties of the thin films as a function of Al concentration have been investigated using atomic force microscopy (AFM) and current-voltage (I-V) measurements at room temperature. AFM images revealed that grain sizes and surface roughness increase with increasing Al concentration. I-V characteristics of the diodes exhibited high and low currents under forward and reverse bias, respectively. The ideality factors (n), rectification ratio (RR) and barrier heights (BH) were found to range from 1.97 to 8.34, 0.84 to 5958 and 0.80 to 0.86 eV for different Al doping concentrations, respectively. These findings showed no monotonic behaviour of the calculated parameters with varying Al doping concentrations. The best electrical characteristic was obtained for the sample n-ZnO: 2 % Al/p-Si, with an ideality factor of 1.97 eV, reverse saturation current of 1.69 ± 10– 8 A, rectification ratio of 5958 at ± 2 V, and barrier height of 0.85 eV. [ABSTRACT FROM AUTHOR]

The article discusses the processes of formation of impurity accumulations in silicon, simultaneously doped with impurity atoms of nickel and iron at a temperature of T = 1473 K. The structural structures and elemental composition of impurity accumulations, which have different morphological parameters, are studied. The results of structural analyzes showed that the formation of any massive accumulations of impurity atoms was not observed in the volume of the initial samples. Unlike the original samples, in the volume of n-Si samples, the formation of accumulations of impurity atoms of various geometric shapes is observed, the sizes of which reach up to several hundred nanometers. It has been revealed that in the volume of impurity accumulations, in addition to atoms of the matrix element silicon and the main impurities of nickel and iron, there are also atoms of so-called technological impurities such as carbon and oxygen. Analyzes of the chemical composition of an impurity accumulation with a spherical shape, the diameter of which is 400 nm, showed that in the central region of this impurity accumulation the percentage of impurity Ni atoms is 30.76 %, and iron atoms are 16.34 %. Also presented are the results of studies of the effect of thermal annealing on the resistivity of n-Si samples at temperatures T = 673 ÷ 1273 K in a time interval of 10 ÷ 120 minutes, followed by sharp quenching. As it turned out, in the dependences of the relative resistivity of n-Si samples on the duration of the annealing time, a certain tendency is observed, according to which, with increasing annealing temperature, the maximum in the dependence curves occurs at a shorter annealing time. Using electron microscopy, structural analyzes of the state of impurity accumulations before and after exposure to thermal annealing were carried out. [ABSTRACT FROM AUTHOR]

Literature review of the new methods of producing polycrystalline and monocrystalline silicon by electron beam and plasma melting developed during the last 10–15 years is presented. A review of publications on determination of oxygen, nitrogen, and hydrogen contents in silicon is given. Express procedures for determination of oxygen content in silicon by reducing melting in a graphite crucible in a flow of helium have been developed, and comparison of these procedures with infrared spectrometry is given. Procedures for determination of hydrogen and nitrogen content in silicon have been developed. [ABSTRACT FROM AUTHOR]

In this study, experiments on the alloying process from screen-printed aluminum (Al) pastes on silicon surfaces for solar cell applications were conducted. We investigated the effect of wafer thickness and screen-printing mesh counts on the Al back surface field (Al-BSF) properties of Czochralski silicon (Cz-Si) solar cells Screens with different mesh counts (150, 200 and 400 mesh) were used to print variable amounts of Al paste (7, 9.4 and 12mg/cm²). Rapid thermal annealing (RTP) annealing processes of 750°C and 800°C for 60s were applied to form AL-BSF. SEM micrographs showed the formation of a rough surface with 4.31m alloying layer over bulk Si wafer. ECV and SIMS analysis showed that an annealing peak temperature of 750°C and an amount of Al paste of 12mg/cm2 are suitable for the creation of an optimal Al-BSF. This work revealed that Al-BSF properties are strongly affected by the mesh counts used in screen-printing of Al paste. However, no monotonic relationship was noticed with the wafer thickness. The mask with 150 meshes allowed to obtain high Al concentrations at the surface, maximum diffusion depth and longer average lifetimes of charge carriers. [ABSTRACT FROM AUTHOR]

Detection of photoluminescence (PL) in traditionally non-luminescent Si material (a typical indirect band semiconductor) attracts great attention both in the scientific aspect and for applications in the field of micro- and nanoelectronics and photoelectronics. Despite the success in technology and understanding of many features inherent to its PL characteristics, many problems have not yet been resolved. In particular – what is the origin of PL lines: quantum size, molecular complexes within SiO2, interface or volume localized states, etc. How to achieve the increase in the PL intensity and to provide excitation of it in different parts of the spectrum. The proposed review systematizes results of studies associated with these problems concerning the original technologies for creation of Si nanocrystals (nc-Si) and various research methods. In conclusion, we summarize the results on the properties of nc-Si-SiO2 luminescent structures depending on their technology of synthesis, photo- and structural features and application prospects for micro- and nanoelectronics as well as photoelectronics. [ABSTRACT FROM AUTHOR]

The interaction of the components in the ternary system Hf-Re-Si was investigated by X-ray powder diffraction, scanning electron microscopy and energy-dispersive X-ray spectroscopy. The isothermal section of the phase diagram at 1000°C was constructed in the full concentration range. The limits of solubility of Si in the binary compounds Hf5Re24 and HfRe2 were found to be 11 and 16 at.%, respectively. The existence of three ternary compounds was confirmed and their crystal structures were refined: HfReSi2 (ZrCrSi2-type structure, space group Pbam, a=9.1271(3) Å, b=10.0356(4) Å, c=8.0708(3) Å), HfReSi (ZrNiAl-type structure, space group P-62m, a=6.9240(2) Å, c=3.3890(1) Å) and -phase Hf9+xRe4-xSi (Hf9Mo4B-type structure, space group P63/mmc, a=8.5835(12) Å, c=8.7135(13) Å). The character of the interaction between the components in the Hf-Re-Si system and related ternary systems is briefly discussed. [ABSTRACT FROM AUTHOR]

The use of alternative and renewable sources of energy supply in energy supply around the world is attracting great and practical interest. The growing interest in them is caused by environmental considerations, on the one hand, and the limited nature of traditional hydrocarbon energy sources, on the other. A special place among alternative and renewable energy sources is occupied by photoelectric solar energy converters, the study of physics, which has become a separate scientific direction of photovoltaics. The development and creation of photocells based on silicon by binary compounds of germanium atoms GexSi1–x in volume is also of particular interest to scientists and specialists. Since the production of silicon with binary compounds of silicon-germanium with certain electrical parameters and structure allows you to significantly expand the spectral region of the sensitivity of photodetectors and the efficiency of photocells based on such materials. [ABSTRACT FROM AUTHOR]

Investigating the formation of inversion layers (IL) at the Si-SiO2 interface in the manufacturing technology of silicon photodetectors, some dynamics of dislocations after isothermal annealing were revealed, which were absent in samples without inversion. After selective etching of samples with inversion layers, localization of dislocations on the periphery of responsive elements (RE) with accumulation of guard rings (GR) or other elements of n+-type topology outside the RE was observed. This testified to the movement of dislocations on the surface of the Si-SiO2 structures with IL in the direction of the periphery of the crystal during isothermal annealing, which contributed to a significant decrease in the density of structural defects in RE. The described phenomenon can be used to obtain highly doped defect-free silicon structures. Since the presence of dislocations or other violations of the crystal lattice negatively affect the parameters of the products. In the case of using the described phenomenon as a technological method of “cleaning” the surface of silicon structures, there is a need for controlled formation of IL. One of the methods of forming inversion layers can be thermal oxidation in hydrochloric acid vapors according to the principle of dry-wet-dry oxidation (for p-type silicon). Another method that does not require additional materials is the annealing of Si-SiO2 structures at a temperature of 900–950 Celsium degrees in a nitrogen atmosphere for ≥ 240 minutes. Inversion channels, in this case, will be formed due to the redistribution and diffusion of metal impurities in the oxide (which were introduced during previous thermal operations) to the Si-SiO2 interface. In the described case, these structural defects after annealing were localized in the GR, which is also an active element of the phododiodes, as it limits the dark current of the RE, accordingly, the dark current of the GR should also be low. To be able to implement this method, it is necessary to create passive n+-regions on the periphery of the crystals, limited by oxide, which will be the locations of defects after annealing. It can be both separate areas of arbitrary shape and a concentric ring outside the GR. Elements that will be the locations of defects on the periphery can be cut off at the stage of separating the substrates into crystalsAfter annealing, it is necessary to remove the IL and form an anti-reflective coating by any known method, since the presence of inversion channels contributes to the growth of dark currents. When examining the morphology of defect localization areas after annealing under high-magnification microscopes and with the help of an atomic force microscope, the formation of hexagonal and round defects, which are partial marginal Frank dislocation loops, was observed. The mechanism of dislocation movement described in this article has not been thoroughly studied by us and requires additional research, but it may be related to Cottrell atmospheres and their interaction with IL. [ABSTRACT FROM AUTHOR]

Зважаючи на потребу ринку в високочутливих кремнієвих p-i-n фотодіодах (ФД) для детектування випромінювання YAG-лазера (довжина хвилі 1,064 мкм), вирішено дослідити методи збільшення їх чутливості, зокрема зміщення максимуму спектральної характеристики чутливості фотоприймача в сторону більших довжин хвиль, а також проаналізувати вплив різних технологічних факторів на її вигляд. Встановлено, що при збільшенні напруги зворотного зміщення зміщується максимум спектральної характеристики в сторону більших довжин хвиль. Також побачено, що при збільшенні часу життя неосновних носіїв заряду та питмого опору кремнію при однаковій напрузі зміщення максимум спектральної характерстики зміщується в сторону більших довжин хвиль. Досягнуто значення максимуму спектральної характеристики 1,01-1,02 мкм. При використанні меза-технології, яка мінімізує деградацію питомого опору матеріалу, подальше зміщення максимуму не відбувається. Також встановлено, що зміна глибини залягання дифузійних шарів ФД може негативно впливати на рівень шумів.

During the preparation of silicon substrates for the manufacture of silicon p-i-n photodiodes, the effect of the presence of chemical-dynamic polishing and the depth of etching on the electrical parameters of the FD was observed. The quality of the polishing operation also affected the optical and photoelectric parameters of the samples. These effects required detailed study. The article investigates defect formation during the operation of chemical-dynamic polishing in the technology of silicon p-i-n FDs and determines the optimal modes of polishing the front and back sides of the substrates. The composition of the etching mixture was HNO3:HF:CH3COOH = 9:2:4. CDP has a significant effect on dark currents. This operation should be performed before heat treatments and before diffusion in the reverse direction to obtain minimum values of the dark current. The optimal polishing depth of the front side of the substrate is 20–25 microns (if we take into account the etching of the reverse side – 35–40 microns in total), the reverse side before boron diffusion – 10–15 microns. The main factors that affect the appearance of defects during polishing have been elucidated. Thus, when the concentration of the components of the polisher medicine for the СDP changes significantly, its properties change significantly – the polisher can become selective, since its composition is similar to the selective polisher of Dash. In order to avoid this, it is necessary to carry out incoming control of component acids. If there are inclusions of another phase in the volume of ingots and, accordingly, on the surface of the substrates, clusters of point microdefects of different sizes, or defects acquired in the process of mechanical processing, there is unevenness of etching and violation of planar parallelism. At a high speed of rotation of the tank with the polisher, the depleted layer of the solution may not have time to form near the surface of the substrates or be “broken off” from the surface by the flow of liquid, which leads to selective etching of the plates. This effect can be manifested in the so-called texturing of substrates, which increases the level of dark current and reduces sensitivity. In the case of the reverse side of the СDP, before boron diffusion, the front side is protected with a chemically resistant varnish. If the thickness of the varnish is insufficient, the formation of punctures in the protective layer is possible. In this case, during the polishing operation, the herbaceous material flows under the varnish layer and the brightening or masking oxide is etched. To prevent the described phenomena, we recommend applying two layers of varnish with intermediate drying. Before the end of the polishing process, it is inadmissible to remove the plates from the container with the herbal agent, because drops of the herbal agent remain on the surface of the substrates. In places where there are drops, a violent reaction begins with the release of nitric acid vapors and strong heating. As a result of this reaction, the plates are strongly etched and spots, depressions-craters and black coating of silicon oxide are formed on their surface. In the event of the appearance of the described damaged surface and the unsuitability of the substrates for further technological operations, it is necessary to remove the surface layers by mechanical methods and again to perform the СDP. [ABSTRACT FROM AUTHOR]

Copyright of Plant Introduction / Ìntrodukcìâ Roslin is the property of M.M. Gryshko National Botanical Garden of the NAS of Ukraine and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Під час виготовлення координатних квадрантних p-i-n фотодіодів з високою напругою зворотного зміщення Uзм≥200 В було спостережено наявність систематичного браку виробів по рівню темнового струму одного (рідше кількох) фоточутливого елемента. Після вимірювання вольт-амперних характеристик побачено, що причиною вказаного є пробій p-n-переходу. Встановлено, що сильний вплив на напругу пробою мають кристалографічні дефекти, зокрема дислокації, механічні порушення, нерівні краї окисної плівки вікон для дифузії, нерівномірний дифузійний профіль, локальний тепловий вплив та ін. Збільшення напруги пробою можливе при збільшенні товщини підкладок, зменшенні концентрації легуючих домішок, чіткому контролю операцій фотолітографії, напилення та приварювання виводів.

Copyright of Eastern-European Journal of Enterprise Technologies is the property of PC TECHNOLOGY CENTER and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Crystalline Silicon (c-Si) remains a dominant photovoltaic material in solar cell industry. Currently, scientific and technological advances enable producing the c-Si solar cells (SCs) efficiency close to the fundamental limit. Therefore, combining the experimental results and those of modeling becomes crucial to further progress in improving the efficiency and reducing the cost of photovoltaic systems. We carried out the experimental characterization of the highly-efficient c-Si SCs and compared with the results of modeling. For this purpose, we developed and applied to the samples under investigation the improved theoretical model to optimize characteristics of highly efficient textured solar cells. The model accounts for all recombination mechanisms, including nonradiative exciton recombination by the Auger mechanism via a deep recombination centers and recombination in the space-charge region. To compare the theoretical results with those of experiments, we proposed empirical formula for the external quantum efficiency (EQE), which describes its experimental spectral dependence near the long-wave absorption edge. The proposed approach allows modeling of the short-circuit current and photoconversion efficiency in the textured crystalline silicon solar cells. It has been ascertained that the dependences of the short-circuit current on the open-circuit voltage and the dark current on the applied voltage at V < 0.6 V coincide with each other. The theoretical results, as compared to the experimental ones, allowed us to validate the developed formalism, and were used to optimize the key parameters of SCs, such as the base thickness, doping level and others. In this work, we have further generalized and refined the analytical approach proposed and used by us earlier to analyze high-efficiency solar cells and model their characteristics. [ABSTRACT FROM AUTHOR]

This work shows that the introduction of nickel atoms in the process of growing silicon crystals enables to obtain a material with stable electrophysical parameters during thermal annealing in the wide temperature range 450...1050 °C and duration (t = 0.5...25 hours). This is the most cost-effective way to create material for semiconductor devices and solar cells with stable parameters. [ABSTRACT FROM AUTHOR]

In the process of carrying out various studies, the problem of an uncontrolled increase in the dark current level of guard-ring photodiodes is observed, being manifested both at a temperature T = 293 K and (largely) when testing devices at elevated temperature (T = 358 K). As it is known, microelectronics technology always uses surface protection (passivation) of semiconductor devices and integrated circuits. In this case, the best solution is a thermally grown SiO2 layer. However, even a surface protected by a dielectric layer does not always remain stable. The article presents the results of the development of a p-i-n photodiode based on high-resistivity p-type silicon of increased responsivity and reduced dark current level of the guard ring at a wavelength of 1064 nm. In the proposed design of the photodiode, the thickness of the peripheral oxide of the crystal is decreased to reduce the influence of the dislocation component of the current and charge states on the inverse characteristics. After phosphorus diffusion (driving-in), phosphorosilicate glass was removed, and additional photolithography was performed, during which the entire layer of peripheral oxide was etched. In the second stage of phosphorus diffusion (distillation), the antireflection oxide 190-220 nm thick was grown in photosensitive areas and at the periphery of the crystal. The photosensitive areas, the guard ring, and the peripheral part of the crystal were separated by an oxide 650700 nm thick grown in the first thermal operation. The production of photodiodes was performed using the same operating conditions as in commercial production, and their parameters were compared with devices manufactured in a standard design. The analysis showed that the photodiodes of the proposed design are characterized by lower and more stable dark currents than commercial devices not only at room temperature, but also at a temperature of 358 K. [ABSTRACT FROM AUTHOR]

Implantation of hydrogen into silicon with subsequent annealing (Smart-Cut Technology) is applied to produce microelectronic devices. Improved characteristics of the resulting structures were achieved by using implantation of deuterium instead of hydrogen. The nanoindentation technique is widely used to measure the hardness H and elasticity modulus E of materials at the nanoscale. The aim of the present work is to investigate the influence of deuterium ion implantation dose on the structure and mechanical properties of single crystal silicon at the nanoscale. The influence of the deuterium ion implantation with an implantation dose ranging from 2×1015 to 1×1018 D/cm² on the structure and mechanical properties of single crystal silicon at the nanoscale has been investigated. Polished (111) silicon samples were implanted at 293 K by using a deuterium ion beam with an ion energy of 24 keV. It was shown by Raman spectroscopy that, depending on the implantation dose, three structural states are formed in silicon: a solid solution of deuterium (D) in Si, a solid solution mixed with the Si amorphous phase, and an amorphous state (a-Si:D) only. Thermal desorption (TD) spectroscopy shows that at low implantation doses, the deuterium TD spectra exhibit a single peak with a maximum at Tmax ~ 575 K. At doses above 5×1017 D/cm², a lowtemperature peak with a maximum at 500 K appears that is indicative of the formation of amorphous hydrogenated silicon a-Si:D. Nanoindentation tests have shown that in the regime of full plasticity in the indenter contact region ( 100 nm), the formation of deuterium solid solution in Si causes an increase in the sample surface hardness up to 14.1 GPa. The surface hardness sharply decreased down to 3.6 GPa with the a-Si:D layer formation. [ABSTRACT FROM AUTHOR]

Nowadays there is an increasing demand for alternative energy sources used in the national economy, industry and everyday life. Solar energy is one of the most promising alternatives to traditional methods of electricity generation. The actual problem is the development of economic and renewable technologies in the production of photovoltaic converters (PVC) based on poly- and monocrystalline silicon. The trends in the creation of the most complex electronic devices based on multilayer epitaxial structures are clearly manifested. At the same time, very high requirements are imposed on the electrophysical properties and perfection of the structure of each layer, the problems of creating perfect and sharp p-n junctions and heteroboundaries on large areas of epitaxial compositions are posed. The article proposes new technological aspects of the formation of silicon nanostructures with transparent coatings, which will significantly improve the quality of PVC on their basis with an efficiency of up to 27 % that will give impetus to the formation of new energy systems. [ABSTRACT FROM AUTHOR]

The effect of all-round hydrostatic pressure (ARHP) on the electrophysical properties of silicon single crystals doped with nickel and cobalt has been studied. After high-temperature diffusion doping in the bulk of n-Si and n-Si samples, accumulations of impurity nickel and cobalt atoms were found. Micrographs of impurity accumulations were obtained by the method of electron probe microanalysis and their structural forms were determined. Depending on their size and shape, these impurity clusters have a single-layer or multilayer structure. Under the influence of ARHP, no significant changes are observed in the value of the resistivity of the initial samples. In contrast to them, in silicon samples doped with nickel or cobalt, under the influence of pressure, the resistivity increases significantly. It was revealed that under the influence of ARHP in the range P = 108-1.6·109 Pa, impurity accumulations of nickel and cobalt in silicon decompose, which leads to an increase in the resistivity of the samples by several times. Comparative analyzes of the morphological parameters of impurity accumulations before and after exposure to ARHP revealed that the process of decay of these clusters occurs in a certain sequence and depends on their size and shape. In n-Si samples, initially, under the influence of ARHP at P = 6·108 Pa, the disintegration of impurity clusters up to 1 μm in size, having needle-like and disc-like shapes, was observed. And in samples of n-Si under the influence of ARHP at P = 4·108 Pa, disintegration of needle-shaped and discshaped impurity clusters up to 0.5 μm in size was observed. Then, at higher ARHP values (Р ≥ 8·108 Pa), decomposition of impurity accumulations of nickel and cobalt with relatively large dimensions, which have a lenticular and spherical shape, was found. [ABSTRACT FROM AUTHOR]

Crystal structure of the ternary compound ErPtSi2 (diffractometer HZG-4a, CuKα-radiation, structure type YIrGe2, Pearson symbol oI32, space group Immm, a=4.19395(6) Å, b=8.41465(13) Å, c=15.85404(19) Å, RB=0.0639, RP=0.0424, and χ²=1.11) was studied by X-ray powder diffraction method. Intermetallide ErPtSi2 is the first representative of YIrGe2 structure type in R-Pt-Si systems. Crystal structures of ternary compounds in the system Er-Pt-Si were analyzed and the structural relationships between them were established according to the systematics of the nearest coordination environment around the less electronegative Er atoms. Compounds, found in the system, were divided into two main types based on the nearest coordination environment, namely on the derivatives of hexagonal and pentagonal prisms with different amounts of additional atoms. These polyhedra exist both alone and in the combination with each other and with cubooctahedra in the structures of the different ternary silicides of erbium. Such a relatively small coordination environment of rare-earth metal atoms can be explained by the structural peculiarities of the ErPt3 binary compound. The coordination polyhedra of the smallest atoms are trigonal prisms with different amounts of additional atoms or cubooctahedra. [ABSTRACT FROM AUTHOR]

Short-circuit current, open-circuit voltage, and photoconversion efficiency of silicon high-efficiency solar cells with all back contact (BCSC) with planar surfaces have been calculated theoretically. In addition to the recombination channels usually considered in this kind of modeling, namely, radiative, Auger, Shockley-Read-Hall, and surface recombination, the model also takes into account the nonradiative trap-assisted exciton Auger recombination and recombination in the space charge region. It is ascertained that these two recombination mechanisms are essential in BCSCs in the maximum power operation regime. The model results are in good agreement with the experimental results from the literature. [ABSTRACT FROM AUTHOR]

Formation of complexes of impurity Mn atoms with impurity atoms of group VI elements (S, Se, Te) in the silicon crystal lattice has been studied. It has been experimentally found that formation of electrically neutral molecules with an ionic-covalent bond between Mn atoms and group VI elements takes place, which possibly leads to formation of new Si2BVI ++Mn binary unit cells in the silicon crystal lattice. It has been shown that in the samples Si〈S, Mn〉, Si〈Se, Mn〉 and Si〈Te, Mn〉, an intense complex formation occurs at the temperatures 1100, 820 and 650 °C, respectively. [ABSTRACT FROM AUTHOR]

The solution to the problem of negative impact on the ecology of fossil fuel consumption is the use of electrochemical energy sources. The special attractiveness has shown of lithium power sources is highlighted and the need to develop new cheap electrode materials and electrolytes with unique properties. The peculiarities of the behavior of lithium and the formation of a layer of reaction products on its surface upon contact with a liquid organic electrolyte have considered. The analysis of the main problems and ways of their solution at use of conversion electrodes of the II type for lithium-ion batteries has carried out. Emphasis is placed on the need to use in the development of new electrode materials of such parameters as capacity loading and accumulated irreversible capacity of the electrodes. The triad “electrode – solid electrolyte interphase – electrolyte” is considered as a basis of a systematic approach to the creation of new generations of lithium power sources. The optimal scenarios have proposed for the formation of an effective solid electrolyte interphase on the surface of the electrodes. The advantages of electrolytes based on fluoroethylene carbonate with synergistic acting additives of vinylene carbonate and ethylene sulfite are described. A new strategy for the use of “secondary” silicon nanomaterials to prevent direct contact of its surface with the electrolyte has considered. It has shown that the solid electrolyte interphase is a dynamic system that self-organizes from the unstable state into a stable one. The electrochemical behavior of electrodes with silicon nanocomposites with high capacity loading and low accumulated irreversible capacity has described. [ABSTRACT FROM AUTHOR]

Copyright of KPI Science News is the property of National Technical University of Ukraine KPI and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In n-Si single crystals, the scattering anisotropy of charge carriers has been studied depending on the compensation level of impurities. Theoretical calculations were carried out within the framework of the anisotropic scattering theory. The electrical conductivity, the Hall effect, and the tensoresistance of silicon crystals with various difference and summary concentrations of impurities were measured. It was established that an increase in the scattering anisotropy in n-Si crystals is practically independent of the degree of their compensation, but is associated only with an increase in the total concentration of ionized impurities. The intra-valley anisotropy of the scattering of charge carriers on dislocations as scatterers was studied for a fixed location of the current with respect to the direction of their preferred orientation. Dislocations (having a distinguished orientation) were introduced into the n-Si crystal by the plastic bending deformation at 1073 K. It has been revealed that in n-Si crystals, the intra-valley anisotropy of the scattering on dislocations is much higher than the scattering anisotropy on the charged point defects. [ABSTRACT FROM AUTHOR]

In this paper, the results of studies of the effect of the diffusion temperature on interaction of clusters of manganese atoms with the sulfur ones have been presented. It has been shown that the electrical parameters of the samples simultaneously doped with sulfur and manganese completely coincide with the parameters of the initial material, i.e. as if they do not contain not only sulfur and manganese, but also thermodonors are not formed. The obtained results make it possible to exclude the possibility of gettering of impurity atoms or formation of some kind of solid solutions, if taking into account the impurity atoms of manganese and sulfur, which complicates their diffusion in the crystal bulk. It has been established that for the initial p-type silicon with the resistivity close to  ~ 10 Ω·cm, the diffusion temperature of 1100 °C is the most optimal one to form clusters with the maximum participation of the introduced sulfur and manganese atoms. [ABSTRACT FROM AUTHOR]

This paper presents the results of computer simulation of the ideality factor of silicon n+–p–p+ structure with iron contamination. The Solar Cells Capacitance Simulator (SCAPS) was the tool used for numerical simulation of these devices. The iron concentration range of 1010 – 1013 cm–3, the acceptor doping level range of 1015 –1017 cm–3, the temperature range of 290 – 340 K, and the base thickness range of 150 – 240 μm were used in the investigation. The double diode model was used to extract the ideality factor. The following cases were considered: (i) uniformly distributed lone interstitial iron atoms; (ii) coexistence of non-uniformly distributed Fei and FeiBs. It has been shown that the ideality factor value is determined by a hole occurring on the Fei level, a trap location, and an intrinsic recombination contribution. The increase in the base thickness leads to a decrease in n value. The sign of change in the ideality factor after FeiBs dissociation depends on temperature, doping level, and iron concentration. [ABSTRACT FROM AUTHOR]

Silicon nanowires (SiNWs) solar cells are becoming an important axis of scientific research especially in the field of new technologies for photovoltaic energy. In this paper, static characteristics (I-V, P-V) and different electrical parameters (ISC, VOC, Imax, Vmax, Pmax and FF) of the SiNWs solar nanocell are studied according to the number of nanowires (n) at room temperature and under global (AM1.5G) illumination spectra using 2D-Atlas SILVACO software. The simulation results show that the silicon nanowires (SiNWs) solar nanocell is characterized by good electrical characteristics and high performance. Increasing the number of nanowires is a good technique for improving the behavior and electrical performance of the SiNWs solar cells. [ABSTRACT FROM AUTHOR]