Владимир Попов

Silicon-on-isolator-nanowires (SOI-NWs) were used for the label-free, real-time biospecific detection of the hepatitis B marker HBsAg and cancer marker α-fetoprotein (AFP). Specific protein–protein recognition was carried out using individual NWs that were functionalized with antibodies. To solve the problem of non-specific binding of target protein molecules to the sensor element the use of a reference NW with immobilized antibodies against non-target proteins was proposed. Using individual SOI-NW surface functionalization allowed the fabrication of a NW array, containing working NWs and reference NWs within one chip. It was shown that this approach allows us to reach a detection limit up to 10−14 and 10−15 M for HBsAg and AFP, respectively. Our investigations also allowed us to reveal the influence of the charged state of the target protein molecules and antibodies in solutions with various pH values on the target protein detection limit. A high sensitivity NW-detector is of interest for the creation of diagnosticums for hepatitis B and for the early stages of cancer diseases.

The properties of silicon-on-insulator nanowires (SOI NWs) fabricated by means of electron lithography and gas etching of SOI in XeF2 or SF6:CFCl3 have been investigated. The method used to fabricate the nanowires was found to require no additional anneal to be given to the final structure for defect removal after nanostructuring. The sensitivity of SOI NWs to negative protein BSA molecules in the pH 7.4 buffer solution was shown to be as high as 1 femtomoles. The gate characteristics of SOI NWs were used to determine the charge density of particles adsorbed on the NW surface. A charge density of 4.6 × 1011 cm−2 was estimated for a 1 femtomole protein concentration. The combined use of open-channel structures with top gates was employed for determining the charge state of structure surfaces after different chemical treatments. Chemical treatments giving rise to a density of the negative charges on the surface of NWs ranging in the interval (7–23) × 1011 cm−2 were examined. Treatments in methanol (after removal of the native oxide) were found to provide stabilization of the SOI surface over a 3-h interval after the treatments.

This work demonstrates the possibility of detection of DNA-oligonucleotide (oDNA) and microRNAs (miRNAs) extracted from blood plasma and associated with breast cancer (BC) in a buffer solution using the nanowire (NW) biosensor based on the silicon-on-insulator (SOI) structures. For biospecific detection, the NW surface was modified with oligonucleotide probes (oDNA-probes) complementary to the well-known miRNA sequence. It has been shown that the SOI-NW biosensor with immobilized oDNA-probes of this type can be used to detect complementary oDNA in a buffer solution with a concentration sensitivity of 10−17 М. The study also demonstrates the use of such biosensor for detection of an increased level of miRNAs isolated from the plasma of breast cancer patients. Application of the NW biosensor enables to distinguish between patients with a diagnosis of breast cancer from those with ovarian cancer (OC) by the value of an increased miRNAs level in the blood plasma of breast cancer patients.

Herein, we have demonstrated highly sensitive real-time biospecific detection of a protein marker of hepatitis C—the core antigen of hepatitis C virus (HCVcoreAg)—using a nanowire (NW) biosensor. The primary element of the NW-biosensor is a chip with p-type conductance, bearing silicon-on-insulator (SOI) nanowire structures on its surface. The nanowire structures are fabricated by gas-plasma treatment and electron beam lithography. The detection specificity was provided by sensitization of the sensor surface with aptamers against HCVcoreAg. The influence of buffer pH on the sensor response signal was studied. The effect of reverse polarity of the biosensor response signal with change from the acidic buffer pH to the neutral one was found. The lowest detectable HCVcoreAg concentration was determined to be 2.0 × 10−15 M in both acidic (pH 5.1) and neutral (pH 7.4) buffer solution. The proposed aptamer-sensitized sensor was also successfully applied to detect HCVcoreAg in serum samples of hepatitis C patients.

Cenospheres are hollow particles in fly-ash, a by-product of coal burning, and are widely used as reinforcement for developing low density composites called syntactic foams. This study investigates the physical, chemical, and thermal properties of cenospheres obtained from 3 different sources, CS1, CS2, and CS3, for the development of syntactic foams. Description of floatation method to separate broken particles is given, and it was seen that up to 11 % of the particles were damaged. Post heat treatment samples show development of SiO2 phase in the cenosphere, which is not present in the as received product. CS3 had the highest quantity of Si element, compared to the other two, showing the difference in the source quality. The particle size distribution for CS2 is very narrow while for the others is much broader. All censopheres have porous walls but the morphology of CS2 is the most uniform and smooth. For the application of metallic layer and subsequent consolidation via spark plasma sintering, CS2 was deemed the most physically, thermally, and chemically suitable.

Aptamer-functionalized silicon-on-insulator nanowires were used for the label-free, real-time biospecific detection of the cancer marker D-NFATc1 protein in the serum.

Information about the characteristics of measuring chips according to their storage conditions is of great importance for clinical diagnosis. In our present work, we have studied the capability of chips to detect nanowire biosensors when they are either freshly prepared or have been stored for either one or two years in a clean room. Potential to detect DNA oligonucleotides (oDNAs)—synthetic analogues of microRNAs (miRNAs) 198 and 429 that are associated with the development of prostate cancer (PCa)—in buffer solution was demonstrated using a nanowire biosensor based on silicon-on-insulator structures (SOI-NW biosensor). To provide biospecific detection, nanowire surfaces were sensitized with oligonucleotide probes (oDNA probes) complimentary to the known sequences of miRNA 183 and 484. In this study it is demonstrated that freshly prepared SOI-NW biosensor chips with n-type conductance and immobilized oDNA probes exhibit responses to the addition of complimentary oDNAs in buffer, leading to decreases in chips’ conductance at a concentration of 3.3 × 10−16 M. The influence of storage time on the characteristics of SOI-NW biosensor chips is also studied herein. It is shown that a two-year storage of the chips leads to significant changes in their characteristics, resulting in “inverse” sensitivity toward negatively charged oDNA probes (i.e., through an increase in chips’ conductance). It is concluded that the surface layer makes the main contribution to conductance of the biosensor chip. Our results indicate that the detection of target nucleic acid molecules can be carried out with high sensitivity using sensor chips after long-term storage, but that changes in their surface properties, which lead to inversed detection signals, must be taken into account. Examples of the applications of such chips for the detection of cancer-associated microRNAs in plasma samples of patients with diagnosed prostate cancer are given. The results obtained herein are useful for the development of highly sensitive nanowire-based diagnostic systems for the revelation of (prostate) cancer-associated microRNAs in human plasma.

In this study, we developed a filtering material for facial masks, which is capable of trapping and subsequent inactivation of bacteria under white light emitting diodes (LED) or sunlight irradiation. Such a functionality is achieved via the modification of the composite membrane based on porous polymer with photocatalytic (TiO2) and plasmonic (Ag) nanoparticles. The porous polymer is produced by means of a computer numerical control machine, which rolls a photoresist/thermoplastic mixture into a ~20-µm-thick membrane followed by its thermal/ultraviolet (UV) hardening and porosification. TiO2 nanoparticles are prepared by hydrothermal and sol-gel techniques. Colloidal synthesis is utilized to fabricate Ag nanoparticles. The TiO2 photocatalytic activity under UV excitation as well as a photothermal effect generated by plasmonic Ag nanoparticles subjected to LED irradiation are studied by the assessment of methylene blue (MB) decomposition. We demonstrate that, in contrast to the filter of the standard facial medical mask, the polymer membrane modified with spray-coated TiO2 and Ag nanoparticles prevents the penetration of bacillus subtilis from its top to bottom side and significantly inhibits bacterial growth when exposed to LED or sunlight.

Herein, we report the development of a highly sensitive nanotechnology-based system—silicon-on-insulator nanowire biosensor for the revelation of microRNAs (miRNAs), associated with the development of glioma in the human. In this system, a sensor chip, bearing an array of silicon nanowire structures, is employed. The sensor chip is fabricated using a top-down technology. In our experiments reported herein, we demonstrated the detection of DNA oligonucleotide (oDNA), which represents a synthetic analogue of microRNA-363 associated with the development of glioma. To provide biospecific detection of the target oligonucleotides, the surface of the nanowire structures is modified with oligonucleotide probes; the latter are complementary to the target ones. The concentration limit of the target oligonucleotide detection, attained using our nanowire biosensor, is at the level of DL~10−17 M. The revelation of the elevated level of glioma-associated miRNA in plasma is also demonstrated.

Nanoribbon chips, based on "silicon-on-insulator" structures (SOI-NR chips), have been fabricated. These SOI-NR chips, whose surface was sensitized with covalently immobilized oligonucleotide molecular probes (oDNA probes), have been employed for the nanoribbon biosensor-based detection of a circular ribonucleic acid (circRNA) molecular marker of glioma in humans. The nucleotide sequence of the oDNA probes was complimentary to the sequence of the target oDNA. The latter represents a synthetic analogue of a glioma marker-NFIX circular RNA. In this way, the detection of target oDNA molecules in a pure buffer has been performed. The lowest concentration of the target biomolecules, detectable in our experiments, was of the order of ~10-17 M. The SOI-NR sensor chips proposed herein have allowed us to reveal an elevated level of the NFIX circular RNA in the blood of a glioma patient.

High conductivity is extremely difficult to obtain in diamond due to its wide band gap and low solubility of dopands. The goal of the investigation was to form a conductor inside HPHT synthetic diamond plates with initial high sheet resistivity ρs (∼1012 Ω/sq) for 400 μm thickness. We used metastable character of diamond structures relative to the graphitization of defective layers formed by 50 keV hydrogen molecular ions at high fluence Φ = (1−13) × 1016 cm−2 ion implantation. High temperature (HT) (500–1600 °C) and vacuum or high pressure (VP/HP) (3 × 10−3/4 × 109 Pa) thermal annealing were chosen to provide the annealing regimes where the graphitic carbon is the most stable phase. Sheet resistance, dropped down up to nine orders of magnitude (ρs ∼ 103 Ω/sq), as well as Raman spectroscopy, and AFM measurements were used to determine electrical, optical and geometrical properties of multilayered heterostructures formed in the set of experiments. Temperature dependences of the conductivity show, that after highest fluencies and annealing temperatures the conductivity is quasimetallic and electronic system is above metal–insulator transition (MIT). At lower fluences and/or annealing temperatures the system is under MIT with the transport of charge carriers being well described by variable range hopping (VRH) mechanism with variable decay length of wave function for localized states. Two or three order of magnitude differences in the conductivity in VP and HP annealed samples are attributed with the higher dimensions of graphite nanocrystals in the case of vacuum annealing. This suggestion coincides with Raman spectra and optimum hopping length for carrier jumps in VRH model for conductivity in the buried layers.

We present measurements of the reduction of light output by plastic scintillators irradiated in the CMS detector during the 8 TeV run of the Large Hadron Collider and show that they indicate a strong dose rate effect. The damage for a given dose is larger for lower dose rate exposures. The results agree with previous measurements of dose rate effects, but are stronger due to the very low dose rates probed. We show that the scaling with dose rate is consistent with that expected from diffusion effects.

The Raman spectroscopy and room-temperature photoluminescence were used to study the properties of the In+ and As+ ion-implanted SiO2 films as a function of annealing temperature Ta at 700–1100 °C. No features of the InAs phase were obtained in the Raman spectra of the native SiO2 films irrespective of Ta. In the ion-implanted SiO2 films encapsulated with Si3N4, three Raman peaks at 202 cm−1, 256 cm−1 and 232 cm−1 corresponding to transverse and longitudinal optical phonons in black As and to longitudinal optical phonons in InAs, respectively, were detected. The SiO2 encapsulation effect on the enhanced InAs phase formation is discussed. A photoluminescence of around 556 nm was observed from the encapsulated ion-implanted SiO2 films and reached its intensity maximum after the annealing at 1000 °C.

A prospective randomized comparative placebo-controlled double-blind study was carried out based on Arterial Indices model of biological age. The study involved 60 men and women aged 40–65 years that were randomly divided into two equal groups of 30 people: the main group and the control one. The study participants from the main group received a dietary supplement containing Siberian fir terpenes, limonene, alpha-linolenic acid, and vitamin E—1 capsule 3 times a day for 90 days. Patients in the comparison group received a placebo according to a similar scheme. Anthropometric and biochemical characteristics of patients from both groups have not undergone any significant changes. According to ultrasound examination of the carotid arteries, we observed a statistically significant decrease in the minimum thickness of the intima-media complex (by 45%). The maximum carotid artery stenosis on the right or left and the expansion index in patients of both groups did not change significantly during treatment. According to the results of applanation tonometry, it was revealed that when taking the studied dietary supplement, the pulse wave velocity significantly decreased compared to the initial one (by 10%). Accordingly, the Arterial Indices biological age decreased by 2.5 years compared to the baseline level in patients of the main group and did not change in patients from the comparison group. Supplementation of fir terpenes in middle-aged patients of both sexes reduces the biological age reflecting the condition of the arteries.

The silicon-on-sapphire (SOS) pseudo-MOSFETs with high-k buried hafnium dioxide interlayer (IL) were investigated after the hydrogen induced Si and HfO2 layer transfer on c-sapphire wafers and annealing at 600–1100 °C. HRTEM, GIXRD and Raman measurements were used to reveal the hafnia phases for furnace and rapid thermal annealings (FA and RTA).

We study microwave photoresponse of a short p-channel MOSFET in the subthreshold regime at temperatures from room to helium. We observe large (several times) enhancement of the MOSFET conductance at 300 K, an order at 77 K, and giant (up to 4–5 orders of magnitude) at 4.2 K. It is shown that this giant enhancement is mainly due to microwave-induced hole tunneling between the MOSFET source and drain. The result obtained exhibits real possibility of developing substantially different kind of microwave radiation detectors fabricated on the basis of ordinary MOS-technology.

The visible room-temperature emission and excitation photoluminescence spectra were studied as a function of the indium and arsenic profiles in the In+ and As+ ion-implanted thermally grown SiO2 films before and after the annealing at the temperature of 900 °C. As + ions at the energy of 40 or 135 keV and In + ions at the energy of 50 keV, providing a projective range ratio RpAs/RpIn of 1 or 3, respectively, were used. Four emission photoluminescence bands, peaked at ∼347 nm (3.57 eV), ∼440 nm (2.81 eV), ∼450 nm (2.75 eV) and ∼500 nm (2.48 eV), were obtained from the 40 keV As+ and 50 keV In+ ion-implanted samples under the excitation wavelength of 300 nm (4.13 eV), 350 nm (3.54 eV), 400 nm (3.10 eV) and 450 nm (2.75 eV), respectively. As the As+ energy increased to 135 keV, under the same excitation conditions, the emission bands peaked at 370 nm (3.35 eV), 420 nm (2.95 eV), 460 nm (2.69 eV) and 505 nm (2.45 eV) dominated in the photoluminescence spectra. The excitation spectra of the observed emission peaks were studied, too. We preliminarily interpret the observed photoluminescence peaks as a result of the T1 → S0 transition of molecular-like clusters associated with the oxygen deficiency provided by In or In–As in ion-implanted SiO2.

The aim of the report is a creation of extremely thin silicon-on-insulator (SOI) structures for quantum devices with layer-by-layer oxidation of smart-cut SOI wafers. The present work deals with investigation of structural, optical and electronic properties of SOI structures by HRTEM, RBS, and spectroscopic ellipsometry (SE), Hall and Pseudo-MOSFET measurements. It is demonstrated that this technology of SOI structure preparation provides a high flatness of interface between buried oxide (BOX) and top silicon layer. Layer-by-layer oxidation with subsequent stripping in diluted HF allows us to save the uniformity and flatness of initial SOI layers up to 10 nm film thickness. A further thinning leads to decrease of oxidation rate and non-uniform growth. A mechanism of these processes is suggested.

Application of micro-Raman spectroscopy for the monitoring of quality of high-k (h-k) dielectric protective layer deposition onto the surface of a nanowire (NW) chip has been demonstrated. A NW chip based on silicon-on-insulator (SOI) structures, protected with a layer of high-k dielectric ((h-k)-SOI-NW chip), has been employed for highly sensitive detection of microRNA (miRNA) associated with oncological diseases. The protective dielectric included a 2-nm-thick Al2O3 surface layer and a 8-nm-thick HfO2 layer, deposited onto a silicon SOI-NW chip. Such a chip had increased time stability upon operation in solution, as compared with an unprotected SOI-NW chip with native oxide. The (h-k)-SOI-NW biosensor has been employed for the detection of DNA oligonucleotide (oDNA), which is a synthetic analogue of miRNA-21 associated with oncological diseases. To provide biospecificity of the detection, the surface of (h-k)-SOI-NW chip was modified with oligonucleotide probe molecules (oDVA probes) complementary to the sequence of the target biomolecule. Concentration sensitivity of the (h-k)-SOI-NW biosensor at the level of DL~10−16 M has been demonstrated.

We have used high pressure high temperature annealing (HPHT) for graphitisation of implanted layers in diamond created by 30 keV Ga+ focused ion beam. Electron microscopy has been used to investigate the implanted layers. It has been revealed that, unlike annealing at vacuum pressure, the graphitization during HPHT annealing occurred through epitaxial growth of graphite (002) planes parallel to (111) diamond planes. High quality of graphite was confirmed by high resolution electron microscopy and electron energy loss spectroscopy.

The detection of CA 125 protein in a solution using a silicon-on-insulator (SOI)-nanowire biosensor with n-type chip has been experimentally demonstrated. The surface of nanowires was modified by covalent immobilization of antibodies against CA 125 in order to provide the biospecificity of the target protein detection. We have demonstrated that the biosensor signal, which results from the biospecific interaction between CA 125 and the covalently immobilized antibodies, increases with the increase in the protein concentration. At that, the minimum concentration, at which the target protein was detectable with the SOI-nanowire biosensor, amounted to 1.5 × 10−16 M.

Abstract Silicon wafers with an ultrathin buried high-k oxide were fabricated by the atomic layer deposition of high-k layers on sapphire and silicon substrates with subsequent silicon layer transfer onto their surfaces by bonding and rapid thermal annealing (RTA). An extremely high thermal stability of hafnia orthorhombic Pca2 1 ferroelectric phase of up to 1100 °C was observed in the silicon-on-ferroelectric structure on the sapphire substrate. Silicon–ferroelectric–silicon structures with hafnia BOX and alumina inclusions also demonstrated increased thermal stability for hafnia or hafnia–zirconia alloys during the RTA treatment up to 900 °C, which makes them fully compatible with current complementary metal oxide semiconductor technology, promising integrated circuits for neuromorphic computation and optoelectronic switching devices.

Some results of the thermal expansion in the antiferromagnetic and paramagnetic states of α-Mn are given. Near TN(95.6 ±0.1°K) a critical index value for thermal expansion is shown to be λ = -0.221 ± 0.008.

Abstract This paper considers a synthesis of graphene flakes on the Ni surface by vacuum thermal treatment of the “sandwich” a‐SiC/Ni multilayer deposited on silicon wafer by magnetron sputtering technique. Lateral size of graphene flake is estimated to be about hundreds of microns while thickness estimated by Raman scattering varied from one to few layers. Atom force microscopy (AFM) is not able to detect graphene flakes in regime of surface topology examination due to large roughness of Ni surface. Employment of scanning Kelvin probe force microscopy (SKPFM) demonstrates a correlation of surface potential and graphene flakes visible by optical microscopy. Moreover, the SKPFM allows to detect the graphene layer even in case of absence of optical contrast from single graphene layer on nickel surface. Using of KPFM the potential differences between Ni and graphene is determined. (© 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

The formation of a multi-crystalline HfO2 film, containing the ferroelectric phase OII (Pmn21) after a high-temperature annealing at 1100 °C, was experimentally observed by HREM for the first time in silicon-on-sapphire (SOS) structures obtained by direct bonding and a hydrogen transfer of silicon layer on Si or C-sapphire substrates, respectively. PEALD HfO2 interlayers with the thickness of 20 nm were deposited on silicon before bonding to reduce the defects and magnitude of their charge at the SOS and silicon-on-insulator (SOI) interfaces. SOS pseudo-MOS transistors demonstrate standard drain-gate characteristics with the same charge carrier mobility as in bulk silicon and a small positive fixed charge (≤1.2 × 1012 cm−2). Moreover, a stable ferroelectric hysteresis with ΔVG ∼700 V observed only in SOS FETs is promising for the embedded memory formation and it extends the functionality of logic circuits. It was concluded that the OII phase is stabilized mainly by a high compressive stress and it can be responsible for the hysteresis in the case of SOS pseudo-MOSFETs opposite to the SOI-structure.

Analysis of the high-k buried oxide phase evolution by the X-ray study, pseudo-MOSFET and CV measurements was used to separate the ferroelectric and interface dipole polarization, and charge trapping up to 300 °C. The thermal budgets during the rapid thermal annealing (RTA) 30 s at temperatures 600 to 1000 °C were established for different hafnia based stacks to ensure the recrystallization of HfO2 layers and preservation of ferroelectric hysteresis. The highest hysteresis was obtained at the RTA stepwise temperature increase to 900 °C for the stack with supercicles HfO2:Al2O3 (10:1).

Ab initio study of the density-dependent population and lifetime of the long-lived $(\ensuremath{\mu}p){}_{2s}$ and the yield of $(\ensuremath{\mu}p){}_{1s}$ atoms with kinetic energy $0.9$ keV have been performed. The direct Coulomb $2s\ensuremath{\rightarrow}1s$ de-excitation is proved to be the dominant quenching mechanism of the $2s$ state at kinetic energy below $2p$ threshold and explain the lifetime of the metastable $2s$ state and high-energy $0.9$ keV component of $(\ensuremath{\mu}p){}_{1S}$ observed at low densities. The cross sections of the elastic, Stark, and Coulomb de-excitation processes have been calculated in the close-coupling approach taking into account both the closed channels and vacuum polarization shifts of the $\mathit{ns}$ states. The cross sections are used as the input data in the detailed study of the atomic cascade kinetics. The theoretical predictions are compared with the known experimental data at low densities. The $47%$ yield of the 0.9 keV $(\ensuremath{\mu}p){}_{1s}$ atoms is predicted for liquid-hydrogen density.

The detection of a hepatitis C protein marker – core antigen of hepatitis C virus (HCVcoreAg) with a nanowire field-effect transistor biosensor, coupled with a microwave generator, has been studied.

The detection of influenza A virions with a nanoribbon detector (NR detector) has been demonstrated. Chips for the detector have been fabricated based on silicon-on-insulator nanoribbon structures (SOI nanoribbon chip), using a complementary metal-oxide-semiconductor (CMOS)-compatible technology—by means of gas-phase etching and standard optical photolithography. The surface of the SOI nanoribbon chip contains a matrix of 10 nanoribbon (NR) sensor elements. SOI nanoribbon chips of n-type conductance have been used for this study. For biospecific detection of target particles, antibodies against influenza virus have been covalently immobilized onto NRs. Influenza A virus detection was performed by real-time registration of the source-drain current through the NRs. The detection of the target viral particles was carried out in buffer solutions at the target particles concentration within the range from 107 to 103 viral particles per milliliter (VP/mL). The lowest detectable concentration of the target viral particles was 6 × 10−16 M (corresponding to 104 VP/mL). The use of solutions containing ~109 to 1010 VP/mL resulted in saturation of the sensor surface with the target virions. In the saturation mode, detection was impossible.

The evolution of oxygen precipitates (OPs) created at 900–1000 K in SiCz with initial oxygen concentration 8 × 1017 cm−3 was studied by DLTS technique. The samples were subjected to high pressure (HP) treatment up to 1.3 GPa at high temperature (HT, 1230–1550 K) which caused a partial dissolution of OP. A new way of studying the oxygen distribution is suggested. It is based on the investigation of an electrically active complex of the oxygen atom with a vacancy (A-center, level Ec − 0.18 eV). A-centers were introduced by 3.0 MeV electron irradiation with dose 1 × 1015 cm−2 and DLTS was used for A-center agglomerates detection. The analysis of data obtained allows one to conclude that the irradiation dose used does not decompose OPs. It has been found that hydrostatic pressure retards OP dissolution at HT treatment through a decrease in the migration energy Ea, coefficient Do and diffusion coefficient D. The effect is explained on the assumption that oxygen diffuses in the form of connected pairs of the oxygen and self-interstitials.

The Coulomb deexcitation of the pionic hydrogen atom in collisions with the hydrogen atom has been studied in the quantum mechanical close-coupling approach. The total Coulomb deexcitation cross sections of $nl\ensuremath{\rightarrow}{n}^{\ensuremath{'}}{l}^{\ensuremath{'}}$ transitions and $l$-averaged cross sections are calculated for initial states with $n=3--8$ and at relative energies $E=0.01\ensuremath{-}100\phantom{\rule{0.3em}{0ex}}\mathrm{eV}$. The strong interaction and vacuum polarization shifts of $ns$ states are taken into account. It is shown that the $\ensuremath{\Delta}n>1$ transitions are very important and make up a substantial fraction of the Coulomb deexcitation cross section (up to $\ensuremath{\sim}47%$).

The paper presents the main regularities of temperature gradient zone melting (TGZM). Theoretical and experimental studies of kinetics and stability of the process and the redistribution of impurities and the main components of solid solutions in TGZM are reviewed. Special attention is paid to the application of the method to growing perfect crystals, epitaxial layers of semiconductor, electrically heterogeneous structures, as well as to physico-chemical investigations.

The process of the radiative kaon capture by nuclei is considered. The total yields of γ-quanta corresponding to the production of different hyperons are calculated.

The Lift-off technique based on high fluence (>3×1016cm−2) implantation of hydrogen (H-) ions has been developed to increase the structural quality and electro-optical properties of the diamond thin membranes. According to the XTEM study the Vacuum Pressure - High Temperature (VPHT) treatment of the H2+ implanted (111) diamond plates at 1200-1600°C and 10−3Pa forms buried glassy like graphite layers in the implanted areas. High Pressure - High Temperature (HPHT) annealing at the same temperatures but under the pressure 4-8 GPa leads to the epitaxial growth of graphite in the buried implanted layers, which could not be etched chemically, but could be easily removed by etching in the anodic cell. Visible light Raman spectroscopy has shown that the H-Lift-off technique is suitable for formation of ultra-thin (down to 30 nm) high quality single crystal diamond membranes and heterostructures. High concentration of nitrogen-vacancy NV− centres (∼1020cm−3) was observed under graphite contacts in thin layer (≤100 nm). Thin, 30 nm single crystal diamond films are the thinnest and largest area single crystal diamond structure produced to date by the Lift-off technique.

The method for the detection of 2,4-dinitrophenol (DNP) in solution is proposed. This method employs the sensors based on silicon nanowire field-effect transistors with protective layers of high- k dielectrics, whose surface is functionalized with an amino silane. Direct highly sensitive detection of DNP has been demonstrated, and the lowest detectable concentration of DNP was determined to be 10 −14 M. Silicon-on-insulator nanowire (SOI-NW) sensors can well be employed for the rapid detection of a wide range of toxic and explosive compounds by selection of sensor surface modification techniques.

MicroRNAs (miRNAs), which represent short (20 to 22 nt) non-coding RNAs, were found to play a direct role in the development of autism in children. Herein, a highly sensitive "silicon-on-insulator"-based nanosensor (SOI-NS) has been developed for the revelation of autism-associated miRNAs. This SOI-NS comprises an array of nanowire sensor structures fabricated by complementary metal-oxide-semiconductor (CMOS)-compatible technology, gas-phase etching, and nanolithography. In our experiments described herein, we demonstrate the revelation of ASD-associated miRNAs in human plasma with the SOI-NS, whose sensor elements were sensitized with oligonucleotide probes. In order to determine the concentration sensitivity of the SOI-NS, experiments on the detection of synthetic DNA analogues of autism-associated miRNAs in purified buffer were performed. The lower limit of miRNA detection attained in our experiments amounted to 10-17 M.

In-memory computing is an attractive solution for reducing power consumption and memory access latency cost by performing certain computations directly in memory without reading operands and sending them to arithmetic logic units. Content-addressable memory (CAM) is an ideal way to smooth out the distinction between storage and processing, since each memory cell is a processing unit. CAM compares the search input with a table of stored data and returns the matched data address. The issues of constructing binary and ternary content-addressable memory (CAM and TCAM) based on ferroelectric devices are considered. A review of ferroelectric materials and devices is carried out, including on ferroelectric transistors (FeFET), ferroelectric tunnel diodes (FTJ), and ferroelectric memristors.

Oncological changes in the prostate are a common cause of death among elderly men. Malignant cells are difficult to identify at early stages, which are asymptomatic. The patient often seeks medical assistance when the disease has already progressed, and the treatment is less effective. Early diagnosis of prostate cancer (PC) is thus one of the priority tasks of modern urology and healthcare in general. The aim of this study is the detection of microRNAs (miRNAs), which are known to be associated with PC. The detection of the target miRNAs in human plasma samples has been performed with a nanoribbon biosensor system, which was based on "silicon-on-insulator" structures (SOI-NR biosensor). In order to provide biospecific detection of the target miRNAs, the surface of individual nanoribbons has been modified with DNA oligonucleotide probes (oDNA probes), whose nucleotide sequences were complementary to those of the target miRNAs. The high detection sensitivity has been demonstrated with the use of model oDNAs, which are complementary to nanoribbon-immobilized oDNA probes, in buffer solutions. The sensitivity threshold was 1.1 × 10-17 M. The successful detection of target miRNAs, isolated from real plasma samples of PC patients, has also been demonstrated. We believe that the development of highly sensitive nanotechnology-based biosensors for PC markers is a step towards personalized medicine.

Raman and photoluminescence spectra were investigated in the In+ and As+ ion-implanted SiO2 films encapsulated with Si3N4 layers as a function of annealing temperature. The optical phonon frequency, as a function of the InAs nanocrystal size, was also calculated within the confined phonon model. The Raman scattering band of around 231 cm−1, close to the low-frequency shifted longitudinal optical phonon mode in the InAs matrix, was observed as the annealing temperature increased to 900 °C. The InAs nanocrystal size of 3 nm was estimated. The strong room-temperature photoluminescence peaking at 550 nm (2.25 eV) was also obtained under the 473 nm wavelength excitation. Its intensity reached a maximum value as the annealing temperature increased to 1000 °C. Its peak position was blue-shifted as the excitation wavelength decreased. The direct irradiative electron and hole recombination in the InAs nanocrystals was proposed as a possible mechanism of this photoluminescence.

physica status solidi (a)Volume 148, Issue 2 p. K65-K67 Short Note Concentration dependences of properties in Pb1−xMnxTe solid solutions E. I. Rogacheva, E. I. Rogacheva Polytechnical University, Kharkov Search for more papers by this authorI. M. Krivulkin, I. M. Krivulkin Polytechnical University, Kharkov Search for more papers by this authorV. P. Popov, V. P. Popov Kharkov State University Search for more papers by this authorT. A. Lobkovskaya, T. A. Lobkovskaya Kharkov State University Search for more papers by this author E. I. Rogacheva, E. I. Rogacheva Polytechnical University, Kharkov Search for more papers by this authorI. M. Krivulkin, I. M. Krivulkin Polytechnical University, Kharkov Search for more papers by this authorV. P. Popov, V. P. Popov Kharkov State University Search for more papers by this authorT. A. Lobkovskaya, T. A. Lobkovskaya Kharkov State University Search for more papers by this author First published: 16 April 1995 https://doi.org/10.1002/pssa.2211480235Citations: 19 21, Frunze St., 310001 Kharkov, Ukraine. 4, Svoboda Sq., 310077 Kharkov, Ukraine. AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL References 1 E. I. Rogacheva, Izv. Akad. Nauk SSSR, Ser. neorg. Mater. 25, 754 (1989). 2 E. I. Rogacheva, N. A. Sinelink, and O. N. Nashchekina, Acta phys. Polon. A 84, 729 (1993). 3 E. I. Rogacheva, Japan. J. appl. Phys. 32, 775 (1993). 4 Y. Furdyna, J. appl. Phys. 64, R29 (1988). 5 D. Stauffer, Introduction to Percolation Theory, Taylor & Francis, London/Philadelphia 1985. 6 D. G. Andrianov, M. N. Pavlov, A. S. Savelev, V. I. Fistul, and G. P. Tsiskarishvili, Soviet Phys. — Semicond. 14, 1292 (1980). 7 T. R. Gavron and N. Cieplak, Acta phys. Polon. A 80, 461 (1991). Citing Literature Volume148, Issue216 April 1995Pages K65-K67 ReferencesRelatedInformation

Differential cross sections of the Coulomb deexcitation in the collisions of excited muonic hydrogen with the hydrogen atom have been studied for the first time. In the framework of the fully quantum-mechanical close-coupling approach both the differential cross sections for the $nl \to n'l'$ transitions and $l$-averaged differential cross sections have been calculated for exotic atom in the initial states with the principle quantum number $n=2 - 6$ at relative motion energies $E_{\rm {cm}}=0.01 - 15$ eV and at scattering angles $\theta_{\rm {cm}}=0 - 180^{\circ}$. The vacuum polarization shifts of the $ns$-states are taken into account. The calculated in the same approach differential cross sections of the elastic and Stark scattering are also presented. The main features of the calculated differential cross sections are discussed and a strong anisotropy of cross sections for the Coulomb deexcitation is predicted.

Annealing of Cz-Si at enhanced pressures gives rise to the creation of oxygen precipitates with smaller sizes and higher concentrations in comparison to the case of annealing at atmospheric pressure. This effect is more pronounced for pressures above 0.1GPa. The pressure (about 1.0GPa) treatment at temperatures below 900°C leads to the stabilization of the OP precursors (of the local oxygen reach areas) and after prolonged annealing to their coexistence with OP. The last effect is most likely connected with a decrease in the OP size with pressure to some critical value which is lower than that needed for OP existence.

Abstract We have investigated the ultimate resolution of e-beam lithography with PMMA resist (MW=1 000 000 and 2 000 000) in-situ during single-electron transistor (SET) formation by means of using an e-beam diameter 5 nm and electron energy 22 keV. The pattern generator and software was from RAITH (PROXY). Writing structures had a minimim size of 40 nm. It was found that if PMMA is at MW=2 000 000, the silicon nanobridges with 15 nm width are available. We have made Ohmic contacts to SOI by Ti/Au evaporation. The resistivity of nanobridges did not change after wet etching in HF. The transistor-like effect was found on pure silicon nanobridges at room temperature in split in-plane gate geometry (IPGFET). The conductance of heavy boron-doped silicon nanobridges at T=4.2 K was investigated. Zero conductivity was found at drain voltage less than 50 mV.

Impact of keV-energy size-selected Arn (n = 16, 27, 41) cluster ions on diamond and graphite is studied both experimentally and by molecular dynamics simulations. For the case of diamond, relatively high cluster kinetic energies (above certain threshold) are required to produce severe radiation damage and originate crater formation on the surface. This is related to very strong chemical bonds and both the melting (or sublimation) point and thermal conductivity of diamond being the highest among the solids. For the case of graphite, which is layered material with weak van der Waals bonds between the graphene planes, significant radiation damage is already introduced by impact of clusters with low kinetic energies (a few tens of eV/atom). However, collisions of the argon clusters cause very elastic response of the graphene planes that leads to efficient closure of the craters which could be formed at the initial stage of impact.

Implantation of hydrogen ions into synthetic single–crystal diamonds followed by subsequent high–temperature annealing and anodic etching of implanted crystals was used to obtain structurally perfect 30–nm thick diamond membranes with optically active NV− centres (area up to several tens mm²) appropriate for use in integral magnetometers and quantum–informatics optoelectronic circuits.

The quantum-mechanical calculations of the differential and integrated cross sections of the elastic scattering, Stark transitions, and Coulomb deexcitation at collisions of excited ${\ensuremath{\mu}}^{\ensuremath{-}}p$ and ${\ensuremath{\mu}}^{\ensuremath{-}}d$ atoms with hydrogen isotope atoms in the ground state are performed. The scattering processes are treated in a unified manner in the framework of the close-coupling approach. The basis used includes both open and closed channels corresponding to all exotic-atom states with principal quantum numbers from $n=1$ up to ${n}_{\mathrm{max}}=20$. The energy shifts of $ns$ states due to electron vacuum polarization and finite nuclear size are taken into account. The kinetics of the atomic cascade of ${\ensuremath{\mu}}^{\ensuremath{-}}p$ and ${\ensuremath{\mu}}^{\ensuremath{-}}d$ atoms are studied in a wide range of relative target densities ($\ensuremath{\varphi}={10}^{\ensuremath{-}8}--1$) within the improved version of the extended cascade model, in which the results of the numerical quantum-mechanical calculations of the cross sections for quantum numbers and kinetic energies of muonic atoms that are of interest for the detailed cascade calculations, are used as input data. Initial $(n,\phantom{\rule{0.16em}{0ex}}l,\phantom{\rule{0.16em}{0ex}}E)$ distributions of muonic atoms at the instant of their formation and the target motion are taken into account explicitly in present cascade calculations. The comparison of the calculated cross sections, the kinetic-energy distributions of muonic atoms at the instant of their $np\ensuremath{\rightarrow}1s$ radiative transitions, as well as the absolute and relative x-ray yields for both muonic hydrogen and muonic deuterium reveals the isotopic effects, which, in principal, may be observed experimentally. The present results are mainly in very good agreement with experimental data available in the literature.

The application of micro-Raman spectroscopy was used for characterization of structural features of the high-k stack (h-k) layer of “silicon-on-insulator” (SOI) nanowire (NW) chip (h-k-SOI-NW chip), including Al2O3 and HfO2 in various combinations after heat treatment from 425 to 1000 °C. After that, the NW structures h-k-SOI-NW chip was created using gas plasma etching optical lithography. The stability of the signals from the monocrine phase of HfO2 was shown. Significant differences were found in the elastic stresses of the silicon layers for very thick (>200 nm) Al2O3 layers. In the UV spectra of SOI layers of a silicon substrate with HfO2, shoulders in the Raman spectrum were observed at 480–490 cm−1 of single-phonon scattering. The h-k-SOI-NW chip created in this way has been used for the detection of DNA-oligonucleotide sequences (oDNA), that became a synthetic analog of circular RNA–circ-SHKBP1 associated with the development of glioma at a concentration of 1.1 × 10−16 M. The possibility of using such h-k-SOI NW chips for the detection of circ-SHKBP1 in blood plasma of patients diagnosed with neoplasm of uncertain nature of the brain and central nervous system was shown.

A nanoribbon biosensor (NRBS) was developed to register synthetic DNAs that simulate and are analogous to miRNA-17-3p associated with colorectal cancer. Using this nanoribbon biosensor, the ability to detect miRNA-17-3p in the blood plasma of a patient diagnosed with colorectal cancer has been demonstrated. The sensing element of the NRBS was a nanochip based on a silicon-on-insulator (SOI) nanostructure. The nanochip included an array of 10 nanoribbons and was designed with the implementation of top-down technology. For biospecific recognition of miRNA-17-3p, the nanochip was modified with DNA probes specific for miRNA-17-3p. The performance of the nanochip was preliminarily tested on model DNA oligonucleotides, which are synthetic analogues of miRNA-17-3p, and a detection limit of ~10-17 M was achieved. The results of this work can be used in the development of serological diagnostic systems for early detection of colorectal cancer.

The induced absorption or annihilation of ${\ensuremath{\pi}}^{\ensuremath{-}}$, ${K}^{\ensuremath{-}}$, and $\overline{p}$ in collisions of hadronic hydrogen atoms in excited states with ordinary hydrogen in the ground state is treated in a unified manner with the elastic scattering, Stark transition, and Coulomb de-excitation in the framework of the close-coupling approach. The close-coupling approach is generalized to include both open andclosed channels corresponding to stable and unstable states of the hadronic atom. Calculations are performed using the basis sets including all states of hadronic atoms with a principal quantum number from $n=1$ up to ${n}_{\mathrm{max}}=8$. The general features of induced-absorption cross sections are studied in a wide range of complex energy-shift values. The cross sections of all processes are calculated for ${\ensuremath{\pi}}^{\ensuremath{-}}p$, ${K}^{\ensuremath{-}}p$, and $\overline{p}p$ atoms with principal quantum numbers $n=2$--8 and kinetic energies from 0.001 up to 100 eV. The validity of the previous quantum-mechanical and semiclassical models is critically discussed.

The Kβ transition in muonic hydrogen was measured with a high-resolution crystal spectrometer. The spectrum is shown to be sensitive to the ground-state hyperfine splitting, the corresponding triplet-to-singlet ratio, and the kinetic energy distribution in the 3p state. The hyperfine splitting and triplet-to-singlet ratio are found to be consistent with the values expected from theoretical and experimental investigations and, therefore, were fixed accordingly in order to reduce the uncertainties in the further reconstruction of the kinetic energy distribution. The presence of high-energetic components was established and quantified in both a phenomenological, i.e. cascade-model-free fit, and in a direct deconvolution of the Doppler broadening based on the Bayesian method.

We show that for impacting argon clusters, both mean projected ranges of the constituents and depths of radiation damage in diamond scale linearly with momentum. The same dependence was earlier found for keV-energy cluster implantation in graphite, thus suggesting the universality of this scaling law. For diamond, a good agreement for the value of displacement energy for the case of cluster impact is found by comparing the calculated target sputtering and experimentally measured depth of radiation damage.

Pion-nucleon scattering lengths are directly related to the ground-state level shift and broadening in pionic hydrogen as well as to the pionic deuterium level shift. The level broadening in deuterium measures the strength of pion threshold-production in proton-proton reactions. However, collisional processes during the atomic de-excitation cascade considerably complicate the analysis of X-ray line shapes in order to extract the hadronic broadening. Therefore, additionally the purely electromagnetic twin system muonic hydrogen was studied. Results of these experiments performed at PSI by using a high-resolution crystal spectrometer are discussed in the context with a new analysis approach for the hadronic broadening.

In this paper we consider an approach to solve the farthest substring problem. This approach is based on an explicit reduction from the problem to the satisfiability problem.

In this paper we consider an approach to solve the minimum test collection problem. This approach is based on an explicit reduction from the problem to the satisfiability problem.

PEALD-grown hafnia and alumina buried oxide (BOX) stacks in silicon-on-insulator (SOI) structures were produced and characterized by XTEM and pseudo-MOSFET techniques. The ferroelectric phases of hafnia were observed by XTEM and SAED. It was shown that the minimal interface states density (IFS) < 1012 cm−2 and the maximal one with a memory window MW ~1 V could be obtained by the right choice of high-k dielectric layer sequence in BOX stack and thermal processing.

Gas-phase etching and optical lithography were employed for the fabrication of a silicon nanoribbon chip (Si-NR chip). The quality of the so-fabricated silicon nanoribbons (Si-NRs) was monitored by optical Raman scattering spectroscopy. It was demonstrated that the structures of the Si-NRs were virtually defect-free, meaning they could be used for highly sensitive detection of biological macromolecules. The Si-NR chips were then used for the highly sensitive nanoelectronics detection of DNA oligonucleotides (oDNAs), which represent synthetic analogs of 106a-5p microRNA (miR-106a-5p), associated with the development of autism spectrum disorders in children. The specificity of the analysis was attained by the sensitization of the Si-NR chip sur-face by covalent immobilization of oDNA probes, whose nucleotide sequence was complementary to the known sequence of miR-106a-5p. The use of the Si-NR chip was demonstrated to al-low for the rapid label-free real-time detection of oDNA at ultra-low (~10−17 M) concentrations.

Application of micro-Raman spectroscopy for the monitoring of quality of nanowire sensor chips fabrication has been demonstrated. Nanowire chips have been fabricated on the basis of «silicon-on-insulator» (SOI) structures (SOI-NW chips). The fabrication of SOI-NW chips was performed by optical litography with gas-phase etching. The so-fabricated SOI-NW chips are intended for highly sensitive detection of brain cancer biomarkers in humans. In our present study, two series of experiments have been conducted. In the first experimental series, detection of a synthetic DNA oligonucleotide (oDNA) analogue of brain cancer-associated microRNA miRNA-363 in purified buffer solution has been performed in order to demonstrate the high detection sensitivity. The second experimental series has been performed in order to reveal miRNA-363 itself in real human plasma samples. To provide detection biospecificity, the SOI-NW chip surface was modified by covalent immobilization of probe oligonucleotides (oDNA probes) complementary to the target biomolecules. Using the SOI-NW sensor chips proposed herein, the concentration detection limit of the target biomolecules at the level of 3.3 × 10−17 M has been demonstrated. Thus, the approach employing the SOI-NW chips proposed herein represents an attractive tool in biomedical practice, aimed at the early revelation of oncological diseases in humans.

The formation of InSb nanocrystals at the bonding Si/SiO2 interface of silicon-on-insulator structure was obtained as a result of the In and Sb atom diffusion from the ion-implanted SiO2 and Si regions, respectively, toward the interface. After the annealing at 1000 °C, the Raman scattering peaks corresponding to the transverse and longitudinal optical phonon mode in the monocrystalline InSb matrix were obtained. As the annealing temperature grew to 1100 °C, the transverse optical phonon mode vanished and the longitudinal optical phonon mode dominated in the spectrum. This effect is explained by matching InSb and Si lattice constants under ion-beam synthesis conditions.

The effect of external stress exerted by enhanced (up to 1.5 GPa) hydrostatic pressure (HP) of argon ambient during annealing of oxygen-implanted silicon (oxygen dose ≤1×1017 cm−2) up to 1470 K on oxygen agglomeration has been investigated by secondary ion mass spectrometry, transmission electron microscopy, and X-ray and photoluminescence methods. HP treatment results in oxygen distribution shift and massive creation of oxygen precipitates, whereas creation of dislocations is strongly suppressed.

In this study, we compared the trap density distributions, Dit, in the band gap of silicon at the Si/thermal SiO2 interface and at the bonded interface of the silicon–on–insulator structure, deduced from deep level transient spectroscopy measurements. The trap energies for the bonded Si/SiO2 interface are localized in the range from Ec–0.17 to Ec–0.37 eV. The lack of the transient SiOx layer at the bonded interface is suggested to lead to a relatively narrow interval of trap energies.

The temperature dependence of the linear expansion coefficients of Cr18Ni10, Cr18Ni15 and Cr18Ni25 alloys has been studied in the temperature range 4.2 to 300 K. Using dilatometric curves the temperature range (195-60 K) of the martensitic transformation on cooling was determined for metastable Cr18Ni10 alloy single crystals. The linear expansion coefficients of the stable structure Cr18Ni25 and Cr18Ni15 and metastable Cr18Ni10 alloys were found to become negative around 25 K; this effect is assumed to be associated with the antiferromagnetic rearrangement in austenite

The evaluation of structural and electrical properties of the SOI wafers during the silicon layer thinning procedure is discussed in the present report. The SOI wafers were obtained using the technology, which involves bonding and hydrogen-induced transfer of silicon layer onto handle oxidized wafer. Interface between the top silicon layer and the buried oxide is the bonded one. Czochralski grown silicon (Cz-Si) or Float Zone grown silicon (Fz-Si) were used as initial material for SOI. The thickness of silicon layer was varied from 590 to 7 nm by using: (1) series of thermal oxidation at the 1000–1100 °C followed by etching of the sacrificial oxide; (2) chemical oxidation and etching in HNO3:HF = 100:1 solution. The SOI layers of different thickness were doped with boron or phosphorus up to concentration 1019 cm−3. Structural defects in SOI wafers were detected by means of optical and scanning electron microscope. The point-contact-transistor method with substrate as a gate was applied for testing of the SOI conductivity. It is shown that the modification of structural properties of SOI occurs during oxidation which appears in the HF defects formation. The main part of the HF defects is formed near the external SOI/SiO2 interface. Growing thermal oxide eliminates the part of generated HF defects. Average size of HF defects is 70–100 nm for Cz-SOI and less than 50 nm for Fz-SOI. HF defects presumably are the effective getters for implanted defects and/or impurity. The presence of HF defects with 104 cm−2 density can result in full loss of the conductivity in Si nanolayers after high-dose implantation and annealing.

The InSb nanocrystals embedded in buried SiO2 layers were obtained by the In+ and Sb+ ion implantation into the SiO2 layers thermally grown on Si wafers followed by the hydrogen transfer of a Si film and high-temperature annealing at 800–1100 °C. Transmission electron microscopy, Raman spectroscopy and photoluminescence were used to study the sample properties. The spherical-shaped InSb nanocrystals distributed close to the implanted atom profiles were obtained in buried SiO2. The InSb TO- and LO-like phonon modes at 187 cm−1 and 195 cm−1 were observed in the Raman spectra. The effect of both phonon quantum confinement and stresses on the phonon frequency shift was calculated. The TO-LO splitting obtained from the ion-beam synthesized InSb nanocrystals was 3 cm−1 less than that from the unstressed bulk monocrystalline InSb. The obtained effect is discussed in the frames of decreasing the transverse effective charge, as well as that of the surface phonon influence. The photoluminescence peak at 1524 nm (0.81 eV) was seen in the low-temperature PL spectra from the samples annealed at 900–1000 °C. Its energy position corresponds to the localized charge carrier energy in the InSb nanocrystals.

In this paper we consider an approach to solve the problem of Hamiltonian path with fixed number of color repetitions for arc-colored digraphs.Our approach is based on usage of local search algorithms to solve a logical model for the problem.

The nanowire (NW) detection is one of fast-acting and high-sensitive methods allowing to reveal potentially relevant protein molecules. A NW biosensor based on the silicon-on-insulator (SOI)-structures was used for biospecific label-free detection of NFAT 1 (D-NFAT 1) oncomarker in real time. For this purpose, SOI-nanowires (NWs) were modified with aptamers against NFAT 1 used as molecular probes. It was shown that using this biosensor it is possible to reach the sensitivity of ~10(-15) M. This sensitivity was comparable with that of the NW biosensor with immobilized antibodies used as macromolecular probes. The results demonstrate promising approaches used to form the sensor elements for high-sensitive disease diagnostics.Odnim iz bystrodeĭstvuiushchikh i vysokochuvstvitel'nykh metodov, pozvoliaiushchikh vyiavliat' potentsial'no vazhnye belkovye molekuly, iavliaetsia metod nanoprovolochnoĭ (NP) detektsii. Nanoprovolochnyĭ biosensor na osnove struktur kremniĭ na izoliatore (KNI), byl ispol'zovan dlia biospetsificheskoĭ detektsii NFAT 1 (D-NFAT 1)-onkomarkera v real'nom vremeni bez metok. Dlia étogo KNI-nanoprovoloki byli modifitsirovany aptamerami k NFAT 1, ispol'zuemymi v kachestve makromolekuliarnykh zondov. Pokazano, chto takoĭ biosensor pozvoliaet dostigat' chuvstvitel'nost' poriadka 10-15 M. Éta chuvstvitel'nost' sopostavima s chuvstvitel'nost'iu, poluchennoĭ na nanoprovolochnom biosensore s immobilizovannymi antitelami, ispol'zuemymi v kachestve makromolekuliarnykh zondov. Rezul'taty demonstriruiut perspektivnost' ispol'zovannykh v rabote podkhodov formirovaniia sensornykh élementov dlia vysokochuvstvitel'noĭ diagnostiki zabolevaniĭ.

A two-gate ferroelectric SOI transistor is proposed as the basic element for a content-addressable memory which will ensure the transition from simple crossbar matrices to deep and recurrent neural networks. The FeFET crossbar architecture and Hamming neural network modeling are described. Modeling the proposed Hamming associative memory implementation confirmed its performance.

The transformational recession in Russia was one of the deepest and longest in the postcommunist countries. Various explanations of the transformational recession are discussed, and an alternative explanation is suggested. The first reason for the output collapse is the adverse supply shock after deregulation of prices associated with greater distortions in the industrial structure and external trade patterns on the eve of the transition. The second factor is the adverse supply shock caused by the collapse of state and nonstate institutions in the late 1980s and early 1990s, resulting in chaotic transformation through crisis management. The third factor is poor economic policies, which included bad macroeconomic policy and import substitution industrial policy. Finally, the speed of reforms (economic liberalization) initially affected performance negatively because enterprises were forced to restructure faster than they possibly could (due to limited investment potential) but improved performance when the economy recovered.

Structural properties of silicon layers oversaturated with implanted hydrogen (up to 20%) are studied by means of IR Fourier spectroscopy, Raman spectroscopy, and high-resolution electron microscopy (HREM). The data obtained by the different methods are found to agree fairly well with one another. Silicon samples implanted up to fluxes (1–3)×1017 cm−2 reveal a layered structure. It is found that just after implantation a surface layer forms which manifests the properties of amorphous silicon. During subsequent heat treatments at 600–800 °C, amorphous layers with embedded silicon nanocrystals form, with a simultaneous decrease in the degree of polymerization of SiH bonds and hydrogen transition in a molecular form. Results of electrical studies of the hydrogenated silicon layers allow us to put forward a new production method for Si:H/c-Si heterostructures based on implanted H which is promising for photoelectrical converters. The new technology makes it possible to avoid the stage of deposition of amorphous silicon from ecologically harmful compounds. The density of states both in the amorphous silicon and at the Si:H/c-Si interface is of the order 5×1017 cm−3 and it is compared to CVD technology.

Characteristic features of the visible photoluminescence (PL) spectra were studied in silicon-on-insulator (SOI) wafers following high-dose (3×1017cm−2) ion implantation of hydrogen and annealing at high hydrostatic pressures. The PL behavior of the SOI material was compared with that of hydrogen-implanted bulk Si. Annealing at a pressure above 6kbars produced a wavelength-selective increase (∼37 times) in the intensity of the visible PL from the implanted SOI structures. The results are explained in terms of the effect of an optical resonant cavity formed between the air/SOI and the Si∕SiO2 interfaces as a result of the high-pressure annealing.

We study the linear polarization properties of the photoluminescence of the neutral and negatively charged nitrogen vacancies and neutral vacancies in diamond crystals as function of their symmetry and their response to strong external magnetic fields. The linear polarization degree, which exceeds 10% at room temperature, and rotation of the polarization plane of their zero-phonon lines significantly depend on the crystal rotation around specific axes demonstrating anisotropic angular evolutions. The sign of the polarization plane rotation is changed periodically through the crystal rotation, which indicates a switching between electron excited states of orthogonal linear polarizations. At external magnetic fields of up to 10 T, the angular dependences of the linear polarization degree experience a remarkable phase shift. Moreover, the rotation of the linear polarization plane increases linearly with rising magnetic field at 6 K and room temperature, for the negatively charged nitrogen vacancies, which is attributed to magneto-optical Faraday rotation.

The detection of CA 125 protein in buffer solution with a silicon-on-insulator (SOI)-based nanoribbon (NR) biosensor was experimentally demonstrated. In the biosensor, sensor chips, bearing an array of 12 nanoribbons (NRs) with n-type conductance, were employed. In the course of the analysis with the NR biosensor, the target protein was biospecifically captured onto the surface of the NRs, which was sensitized with covalently immobilized aptamers against CA 125. Atomic force microscopy (AFM) and mass spectrometry (MS) were employed in order to confirm the formation of the probe–target complexes on the NR surface. Via AFM and MS, the formation of aptamer–antigen complexes on the surface of SOI substrates with covalently immobilized aptamers against CA 125 was revealed, thus confirming the efficient immobilization of the aptamers onto the SOI surface. The biosensor signal, resulting from the biospecific interaction between CA 125 and the NR-immobilized aptamer probes, was shown to increase with an increase in the target protein concentration. The minimum detectable CA 125 concentration was as low as 1.5 × 10−17 M. Moreover, with the biosensor proposed herein, the detection of CA 125 in the plasma of ovarian cancer patients was demonstrated.

Thin nitrogen doped layers with ~1 ppm NV center ensembles were created by the hydrogen implantation of type Ib or hot nitrogen implantation in the high purity type IIa and IIb high pressure high temperature-grown (HPHT) diamond and followed HPHT treatment up to 1500 °C at 7 GPa. The dephasing time T2* = 0.4–0.9 μs was obtained even for the implanted nitrogen content of ~100 ppm. The data evidence the absence of other spin active defects besides the implanted nitrogen atoms in neutral states, determined this decoherence.

Silicon-on-insulator (SOI) structures were fabricated by bonding using a new variant of Smart-Cut technology. As-bonded SOI structures are annealed at high temperature (1100°C) for removal of hydrogen, radiation defects and stresses at the bonding interface. The transformation of structural parameters in as-bonded and annealed SOI structures was investigated by high-resolution X-ray diffraction. The large strain observed for as-bonded SOI structures is relaxed during annealing at high temperature and final SOI wafer has strain-free top silicon layer due to defect annealing and viscous flow of SiO2. FWHM value for SOI film is higher than that for typical silicon single crystal and is caused by mosaic-like structure only.