Infrared photoresponse of GeSiSn p-i-n photodiodes based on quantum dots, quantum wells, pseudomorphic and relaxed layers.

Structural and photoelectric properties of p-i-n photodiodes based on GeSiSn/Si multiple quantum dots both on Si and silicon-on-insulator (SOI) substrates were investigated. Elastic strained state of grown films was demonstrated by x-ray diffractometry. Annealing of p-i-n structures before the mesa fabrication can improve the ideality factor of current-voltage characteristics.

Infrared photoresponse of GeSiSn p-i-n photodiodes based on quantum dots, quantum wells, pseudomorphic and relaxed layers.

Structural and photoelectric properties of p-i-n photodiodes based on GeSiSn/Si multiple quantum dots both on Si and silicon-on-insulator (SOI) substrates were investigated. Elastic strained state of grown films was demonstrated by x-ray diffractometry. Annealing of p-i-n structures before the mesa fabrication can improve the ideality factor of current-voltage characteristics.

Comprehensive Review on the Impact of Chemical Composition, Plasma Treatment, and Vacuum Ultraviolet (VUV) Irradiation on the Electrical Properties of Organosilicate Films.

Organosilicate glass (OSG) films are a critical component in modern electronic devices, with their electrical properties playing a crucial role in device performance. This comprehensive review systematically examines the influence of chemical composition, vacuum ultraviolet (VUV) irradiation, and plasma treatment on the electrical properties of these films. Through an extensive survey of literature and experimental findings, we elucidate the intricate interplay between these factors and the resulting alterations in electrical conductivity, dielectric constant, and breakdown strength of OSG films.

Engineering of graphene-based composites with hexagonal boron nitride and PEDOT:PSS for sensing applications.

A unique nanomaterial has been developed for sweat analysis, including glucose level monitoring. Simple resusable low-cost sensors from composite materials based on graphene, hexagonal boron nitride, and conductive PEDOT:PSS (poly(3,4-ethylenedioxythiophene)polystyrene sulfonate) polymer have been developed and fabricated 2D printing on flexible substrates. The sensors were tested as biosensors using different water-based solutions.

Graphene-based multifunctional humidity sensors with an ultrahigh current response.

Prospective composites, based on graphene (G) and hexagonal boron nitride (h-BN) nanoparticles, synthesized using a plasma jet and conducting polymer PEDOT:PSS, were used to create and study a set of sensors in the current study. The composites used were G:PEDOT:PSS (GPP) and G:h-BN:PEDOT:PSS (GBNPP). The PEDOT:PSS content in the composites was 10 wt%, and the ratio of G : h-BN was 1 : 1 in GBNPP.

Vapor-Phase-Deposited Ag/Ir and Ag/Au Film Heterostructures for Implant Materials: Cytotoxic, Antibacterial and Histological Studies.

Using gas-phase deposition (Physical Vapor Deposition (PVD) and Metal Organic Chemical Vapor Deposition (MOCVD)) methods, modern implant samples (Ti alloy and CFR-PEEK polymer, 30% carbon fiber) were functionalized with film heterostructures consisting of an iridium or gold sublayer, on the surface of which an antibacterial component (silver) was deposited: Ag/Ir(Au)/Ti(CFR-PEEK). The biocidal effect of the heterostructures was investigated, the effect of the surface relief of the carrier and the metal sublayer on antibacterial activity was established, and the dynamics of silver dissolution was evaluated. It has been shown that the activity of Ag/Ir heterostructures was due to high Ag release rates, which led to rapid (2-4 h) inhibition of growth.

Ultrafast electron dynamics in a topological surface state observed in two-dimensional momentum space.

We study ultrafast population dynamics in the topological surface state of Sb[Formula: see text]Te[Formula: see text] in two-dimensional momentum space with time- and angle-resolved two-photon photoemission spectroscopy. Linearly polarized mid-infrared pump pulses are used to permit a direct optical excitation across the Dirac point. We show that this resonant excitation is strongly enhanced within the Dirac cone along three of the six [Formula: see text]-[Formula: see text] directions and results in a macroscopic photocurrent when the plane of incidence is aligned along a [Formula: see text]-[Formula: see text] direction.

Bottom-Up Generated Height Gauges for Silicon-Based Nanometrology.

Steady progress in integrated circuit design has forced basic metrology to adopt silicon lattice parameter as a secondary realization of the SI meter that lacks convenient physical gauges for precise surface measurements at a nanoscale. To employ this fundamental shift in nanoscience and nanotechnology, we propose a set of self-organized silicon surface morphologies as a gauge for height measurements within the whole nanoscale (0.3-100 nm) range.

Radial artery pulse wave velocity: a new characterization technique and the instabilities associated with the respiratory phase and breath-holding.

. Pulse wave velocity (PWV) is a key diagnostic parameter of the cardiovascular system's state. However, approaches aimed at PWV characterization often suffer from inevitable drawbacks.

Optical properties of extreme tellurium nanowires formed in subnanometer-diameter channels.

Single tellurium (Te) chains attract much attention as extreme nanowires with unique electronic and spintronic properties. Here, we encapsulate Te from a melt into channels of zeolites AFI (∼0.73 nm-channel diameter) and mordenite (MOR, ∼0.

Ferroelectric Devices for Content-Addressable Memory.

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.

Integral Algorithms to Evaluate TiO and N-TiO Thin Films' Cytocompatibility.

Titanium oxide (TiO) and oxynitride (N-TiO) coatings can increase nitinol stents' cytocompatibility with endothelial cells. Methods of TiO and N-TiO sputtering and cytocompatibility assessments vary significantly among different research groups, making it difficult to compare results. The aim of this work was to develop an integral cytocompatibility index (ICI) and a decision tree algorithm (DTA) using the "EA.

Engineering of graphene flakes in the process of synthesis in DC plasma jets.

During the pyrolysis of hydrocarbons in helium plasma jets in a plasma-chemical reactor, graphene flakes of a different structure and resistance were obtained. The presence of hydrogen in these structures was established by physicochemical methods, and its content depends on the pressure in the plasma-chemical reactor and the composition of a plasma-forming system. In addition to hydrogen, a relatively low concentration of oxygen atoms is present in the graphene flakes.

Kinetics of Catalyst-Free and Position-Controlled Low-Pressure Chemical Vapor Deposition Growth of VO Nanowire Arrays on Nanoimprinted Si Substrates.

In the present article, the position-controlled and catalytic-free synthesis of vanadium dioxide (VO) nanowires (NWs) grown by the chemical vapor deposition (CVD) on nanoimprinted silicon substrates in the form of nanopillar arrays was analyzed. The NW growth on silicon nanopillars with different cross-sectional areas was studied, and it has been shown that the NWs' height decreases with an increase in their cross-sectional area. The X-ray diffraction technique, scanning electron microscopy, and X-ray photoelectron spectroscopy showed the high quality of the grown VO NWs.

Evolution of the Microstructure and Phase Composition of the Products Formed in the Reaction between Iridium and WB.

In the present study, we perform a systematic examination of the products formed by mixing and heating of tungsten boride and iridium powders at different ratios in a broad temperature range using qualitative and quantitative X-ray analysis and time-of-flight neutron diffraction (TOF-ND), in combination with scanning electron microscopy/energy-dispersive spectroscopy (SEM/EDS) performed at different accelerating voltages. The well-known and unknown ternary W-Ir-B phases were detected. The Vickers microhardness value for the new ternary WIrB boride was measured.

The Nature of Ferromagnetism in a System of Self-Ordered α-FeSi Nanorods on a Si(111)-4° Vicinal Surface: Experiment and Theory.

In this study, the appearance of magnetic moments and ferromagnetism in nanostructures of non-magnetic materials based on silicon and transition metals (such as iron) was considered experimentally and theoretically. An analysis of the related literature shows that for a monolayer iron coating on a vicinal silicon surface with (111) orientation after solid-phase annealing at 450-550 °C, self-ordered two-dimensional islands of α-FeSi displaying superparamagnetic properties are formed. We studied the transition to ferromagnetic properties in a system of α-FeSi nanorods (NRs) in the temperature range of 2-300 K with an increase in the iron coverage to 5.

Ion Drift and Polarization in Thin SiO and HfO Layers Inserted in Silicon on Sapphire.

To reduce the built-in positive charge value at the silicon-on-sapphire (SOS) phase border obtained by bonding and a hydrogen transfer, thermal silicon oxide (SiO) layers with a thickness of 50-310 nm and HfO layers with a thickness of 20 nm were inserted between silicon and sapphire by plasma-enhanced atomic layer deposition (PEALD). After high-temperature annealing at 1100 °C, these layers led to a hysteresis in the drain current-gate voltage curves and a field-induced switching of threshold voltage in the SOS pseudo-MOSFET. For the inserted SiO with a thickness of 310 nm, the transfer transistor characteristics measured in the temperature ranging from 25 to 300 °C demonstrated a triple increase in the hysteresis window with the increasing temperature.

Biological Studies of New Implant Materials Based on Carbon and Polymer Carriers with Film Heterostructures Containing Noble Metals.

This paper presents pioneering results on the evaluation of noble metal film hetero-structures to improve some functional characteristics of carbon-based implant materials: carbon-composite material (CCM) and carbon-fiber-reinforced polyetheretherketone (CFR-PEEK). Metal-organic chemical vapor deposition (MOCVD) was successfully applied to the deposition of Ir, Pt, and PtIr films on these carriers. A noble metal layer as thin as 1 µm provided clear X-ray imaging of 1−2.

Graphene: Hexagonal Boron Nitride Composite Films with Low-Resistance for Flexible Electronics.

The structure and electric properties of hexagonal boron nitride (h-BN):graphene composite with additives of the conductive polymer PEDOT:PSS and ethylene glycol were examined. The graphene and h-BN flakes synthesized in plasma with nanometer sizes were used for experiments. It was found that the addition of more than 10 mass% of PEDOT:PSS to the graphene suspension or h-BN:graphene composite in combination with ethylene glycol leads to a strong decrease (4-5 orders of magnitude, in our case) in the resistance of the films created from these suspensions.

Interdisk spacing effect on resonant properties of Ge disk lattices on Si substrates.

The light reflection properties of Ge disk lattices on Si substrates are studied as a function of the disk height and the gap width between disks. The interdisk spacing effect is observed even at such large gap widths as 500 nm. The gap width decrease leads to the appearance of the reflection minimum in the short wavelength region relative to one originated from the magnetic and electric dipole resonances in individual Ge disks, thereby essentially widening the antireflection properties.

Suspended semiconductor nanostructures: physics and technology.

The current state of research on quantum and ballistic electron transport in semiconductor nanostructures with a two-dimensional electron gas separated from the substrate and nanoelectromechanical systems is reviewed. These nanostructures fabricated using the surface nanomachining technique have certain unexpected features in comparison to their non-suspended counterparts, such as additional mechanical degrees of freedom, enhanced electron-electron interaction and weak heat sink. Moreover, their mechanical functionality can be used as an additional tool for studying the electron transport, complementary to the ordinary electrical measurements.

Screen-Printed Structures from a Highly Conductive Mildly Oxidized Graphene Suspension for Flexible Electronics.

In this study, the screen-printed flexible humidity sensor and supercapacitor structures from a suspension of mildly oxidized graphene (MOG) was obtained. MOG suspension with a low atomic oxygen content (~20%) was synthesized by electrochemical exfoliation of natural graphite in an aqueous solution of ammonium sulfate. MOG films (average thickness 5 μm) with a surface resistance of 10-10 kΩ/sq were obtained by screen printing on a flexible substrate.