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Boron penetration through 5 nm to 8 nm gate dielectrics grown in O2 or N2O via RTO increases exponentially with decreasing oxide thickness. A physical model describes the thickness dependence observed for boron penetration. The model enables prediction of the minimum oxide thickness required to inhibit boron penetration. The significance of boron-induced threshold voltage variation in ULSI technologies is studied.

Focuses on a study which measured the root-mean-square width of the buried crystalline/amorphous silicon(001)/silicon oxide[sub2] interface. Properties of metal-oxide semiconductor devices; Reverse correlation of interface width and oxide thickness; Difference between the rate of smoothing for wet and dry oxides.

We investigate the spectral characteristics of the Be/X-ray binary system, EXO 051910+3737.7, in which Be/X-ray systems are the largest sub-class of high-mass X-ray binaries. Spectroscopic observations are taken by the Thai National Telescope (TNT) with a Medium-RESolution spectrograph (MRES) instrument for seven nights spanning from 2020 to 2021. Our primary focus is directed towards the analysis of two Balmer lines, namely Hα and Hβ, given that Be stars typically exhibit emission features in at least one of these hydrogen Balmer lines during certain phases. Our observations reveal split Balmer emission lines throughout the entire duration of our monitoring. Double Gaussian profiles were employed for line fitting to characterize these lines. The presence of double peaks in the Balmer lines indicates the presence of asymmetries within the circumstellar disc. We then analyze V/R variations and the changes in Hβ spectra. Our analysis of V/R variation which Violet (V) and Red (R) peak intensity components, revealed rapid fluctuations occurring within a single day, although determining the precise periodicity was constrained by instrumental limitations and the duration of observability. Furthermore, employing observed the wavelength differences (Δλ) in conjunction with typical Be star parameters allowed us to estimate the radius (rβ) of the Hβ emitting envelope. The average value was calculated to be 2.585r*, with a standard deviation of 0.050r*. [ABSTRACT FROM AUTHOR]

We have investigated the crystallization of amorphous oxides that are considered likely candidates to replace amorphous SiO[sub 2] as the gate dielectric in advanced field-effect transistors. To avoid crystallization, the mole fraction of main-group oxide in the Zr–Si–O, Zr–Al–O, and Hf–Si–O systems must be greater than 83%, 65%, and 78%, respectively, leading to a maximum useful dielectric constant of only 6.9, 12.7, and 6.6, respectively. We conclude that the silicate systems are not likely to be useful as replacements for SiO[sub 2], while aluminates are more promising. © 2003 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Electrical and structural characteristics of thin thermally oxidized yttrium layers on Si and on Si covered with 40 Å of SiO2 have been investigated. The factor of ∼ four advantage in the dielectric constant of Y2O3 over SiO2, coupled with extremely low leakage current density of better than 10-10 A/cm2 in a field of 1.9 MV/cm, sufficiently high breakdown strength, and well-behaved capacitance-voltage characteristics makes Y2O3 a viable candidate for Si very large scale integration applications, at least in passive devices. High-resolution transmission electron microscopy reveals the structure of the composite dielectric and provides good agreement between calculated and experimental capacitance. [ABSTRACT FROM AUTHOR]

Examines the growth temperature dependence of silicon/silica interface. Use of rapid thermal oxidation; Effects of temperature on interfacial roughness; Preference of growing thin oxide films at high temperatures.

Researchers have developed a one-step plug-and-probe technique using van der Waals assimilated high-k dielectrics and contacts to fabricate top-gated transistors for delicate electronic materials. This technique allows for the integration of materials such as two-dimensional semiconductors and lead halide perovskites, which are important for compact silicon-based electronics but are incompatible with traditional fabrication methods. The plug-and-probe approach enables the creation of atomically clean dielectric interfaces and exhibits excellent gate configuration and low gate leakage. It has the potential for scalable fabrication and can be applied to a variety of materials, including large-area chemical vapor deposition-grown transition metal dichalcogenides and lead halide perovskite thin films. [Extracted from the article]

The scenario involving the alarming growth of bacterial resistance has never been more worrying. Increasingly selective and sophisticated bacterial strains resistant to traditional antibiotics are a threat to the health system worldwide. Therefore, antimicrobial peptides (AMPs) represent a promising path in the fight against multidrug‐resistant pathogens. Here, using an in silico methodology, employing robust software, the present study aims to analyze the chymo32 peptide, obtained by enzymatic fragmentation of the escapin protein to test its possible antibacterial effects, correlating them with their physical–chemical nature. In this study, we used in silico predictions such as structural prediction, physicochemical properties, hemolytic activity, and prediction of activity for immunomodulation. Among the 378 peptide fragments obtained from the original protein, chymo32 was the only peptide selected in the field of screenings involving sequence length, cationicity, hydrophobicity, and prediction of antibacterial activity. The physical–chemical properties of chymo32 are promising, as well as its prediction as AMP. The immunomodulation predictions showed no immunogenic potential, which indicates greater safety in the posterior steps in vitro, also highlighting the absence of hemolytic activity, one of the main problems associated with AMPs in the therapeutic clinic. [ABSTRACT FROM AUTHOR]

Identification technology based on biometrics is a branch of research that employs the unique individual traits of humans to authenticate identity, which is the most secure method of identification based on its exceptional high dependability and stability of human biometrics. Common biometric identifiers include fingerprints, irises, and facial sounds, among others. In the realm of biometric recognition, fingerprint recognition has gained success with its convenient operation and fast identif ication speed. Different fingerprint collecting techniques, which supply fingerprint information for fingerprint identification systems, have attracted a significant deal of interest in authentication technology regarding fingerprint identification systems. This work presents several fingerprint acquisition techniques, such as optical capacitive and ultrasonic, and analyzes acquisition types and structures. In addition, the pros and drawbacks of various sensor types, as well as the limits and benefits of optical, capacitive, and ultrasonic kinds, are discussed. It is the necessary stage for the application of the Internet of Things (IoT). [ABSTRACT FROM AUTHOR]

Conjugated oligoelectrolytes (COEs) are an emerging class of amphiphilic antimicrobial compounds with a modular molecular framework suitable for simple chemical derivatization. Here, a series of COE derivatives with a stilbene‐conjugated segment and triphenylphosphonium (TPP) pendant groups was designed and synthesized to understand how lipophilic cationic groups impact antimicrobial activity. In vitro evaluations against ESKAPE pathogens showed broad‐spectrum activity towards multi‐drug resistant (MDR) bacteria and mycobacteria, with TPP groups enhancing antimicrobial activity towards clinically relevant Gram‐negative strains compared to their ammonium analogues. We studied the interactions of DM6P, the most active TPP‐COE compound, with various membrane assays. Treatment of bacterial cells with DM6P showed enhanced permeability of cell membranes without inducing the development of significant bacterial resistance. Moreover, DM6P eliminated 99.99 % of methicillin‐resistant Staphyloccocus aureus (MRSA) in an in vivo wound model. These results represent a promising chemical strategy for increasing the activity spectrum of membrane‐active COE antibiotics to tackle challenging drug‐resistant targets. [ABSTRACT FROM AUTHOR]

Visible-light-responsive graphite-embedded titanium dioxide nanofibers (G-TiO2 NFs), prepared by electrospinning and post-treatment with rhodizonic acid (RhA), show biocidal effects against E. coli and S. aureus when excited with visible light. The red absorption shift of surface-modified G-TiO2 NFs with RhA of about 1.1 eV is a consequence of interfacial charge transfer (ICT) complex formation facilitated by a condensation reaction between hydroxyl groups originating from the ligand and surface TiO2. The optical properties of the inorganic–organic hybrid are studied in-depth by density functional theory (DFT) calculations using a cluster model. The prepared samples are thoroughly characterized using X-ray diffraction (XRD) analysis, electron paramagnetic resonance spectroscopy (EPR), Fourier-transform infra-red (FTIR) spectroscopy, Raman spectroscopy, and X-ray photoelectron spectroscopy (XPS). Under visible light illumination, surface-modified G-TiO2 NFs display a near-to ideal biocidal effect against E. coli and S. aureus and no cytotoxicity was observed toward L929 fibroblast cells. Overall, the experimental results suggest that fabrics based on surface-modified G-TiO2 NFs with RhA can be potentially used to control the persistence and spread of bacterial infection. [ABSTRACT FROM AUTHOR]

For high electron mobility transistors (HEMTs) power transistors based on AlGaN/GaN heterojunction, p-GaN gate has been the gate topology commonly used to deplete the two dimensional electron gas (2-DEG) and achieve a normally-OFF behavior. But fully recessed MIS gate GaN power transistors or MOSc-HEMTs have gained interest as normally-OFF HEMTs thanks to the wider voltage swing and reduced gate leakage current when compared to p-GaN gate HEMTs. However the mandatory AlGaN barrier etching to deplete the 2-DEG combined with the nature of the dielectric/GaN interface generates etching-related defects, traps, and roughness. As a consequence, the threshold voltage (VTH) can be unstable, and the electron mobility is reduced, which presents a challenge for the integration of a fully recessed MIS gate. Recent developments have been studied to solve this challenge. In this paper, we discuss developments in gate recess with low impact etching and atomic layer etching (ALE) alongside surface treatments such as wet cleaning, thermal or plasma treatment, all in the scope of having a surface close to pristine. Finally, different interfacial layers, such as AlN, and alternative dielectrics investigated to optimize the dielectric/GaN interface are presented. [ABSTRACT FROM AUTHOR]

In previous studies we have described the therapeutic action of luminescent dinuclear ruthenium(II) complexes based on the tetrapyridylphenazine, tpphz, bridging ligand on pathogenic strains of Escherichia coli and Enterococcus faecalis. Herein, the antimicrobial activity of the complex against pernicious Gram‐negative ESKAPE pathogenic strains of Acinetobacter baumannii (AB12, AB16, AB184 and AB210) and Pseudomonas aeruginosa (PA2017, PA_ 007_ IMP and PA_ 004_ CRCN) are reported. Estimated minimum inhibitory concentrations and minimum bactericidal concentrations for the complexes revealed the complex shows potent activity against all A. baumannii strains, in both glucose defined minimal media and standard nutrient rich Mueller‐Hinton‐II. Although the activity was lower in P. aureginosa, a moderately high potency was observed and retained in carbapenem‐resistant strains. Optical microscopy showed that the compound is rapidly internalized by A. baumannii. As previous reports had revealed the complex exhibited no toxicity in Galleria Mellonella up to concentrations of 80 mg/kg, the ability to clear pathogenic infection within this model was explored. The pathogenic concentrations to the larvae for each bacterium were determined to be≥105 for AB184 and≥103 CFU/mL for PA2017. It was found a single dose of the compound totally cleared a pathogenic A. baumannii infection from all treated G. mellonella within 96 h. Uniquely, in these conditions thanks to the imaging properties of the complex the clearance of the bacteria within the hemolymph of G. mellonella could be directly visualized through both optical and transmission electron microscopy. [ABSTRACT FROM AUTHOR]

A series of different high κ dielectrics such as HfO2, ZrO2, and Al2O3 thin films were studied as an alternative material for the possible replacement of traditional SiO2. These large areas, as well as conformal dielectrics thin films, were grown by the atomic layer deposition technique on a p-type silicon substrate at two different deposition temperatures (150 and 250 °C). Atomic force microscopic study reveals that the surface of the films is very smooth with a measured rms surface roughness value of less than 0.4 nm in some films. After the deposition of the high κ layer, a top metal electrode was deposited onto it to fabricate metal oxide semiconductor capacitor (MOSCAP) structures. The I–V curve reveals that the sample growth at high temperatures exhibits a high resistance value and lower leakage current densities. Frequency-dependent (100 kHz to 1 MHz) C–V characteristics of the MOSCAPs were studied steadily. Furthermore, we have prepared a metal oxide semiconductor field-effect transistor device with Al-doped ZnO as a channel material, and the electrical characteristic of the device was studied. The effect of growth temperature on the structure, surface morphology, crystallinity, capacitance, and dielectric properties of the high κ dielectrics was thoroughly analyzed through several measurement techniques, such as XRD, atomic force microscopy, semiconductor parameter analysis, and ultraviolet-visible spectroscopy. [ABSTRACT FROM AUTHOR]

A series of novel piperazine based cinnamic acid bearing coumarin derivatives were designed and synthesized by piperazine based cinnamic acids esterification with 4‐hydroxycoumarin and characterized by various spectral techniques like infrared, 1H nuclear magnetic resonance (NMR), 13C NMR, and mass. The novel bioactive compounds (7a‐7m) screen their potential against different bacterial and fungal strains. Compound 7g (minimum inhibitory concentration [MIC] = 12.5 µg/ml) exhibited potent antibacterial activity against Escherichia coli strain. Compounds 7d, 7f, 7g, 7k, 7l, and 7m showed potent antibacterial activity against all bacterial strains. Compounds 7a, 7g, 7h, 7k, 7l, and 7m exhibited potent antifungal activity against all fungal strains. Furthermore, a molecular docking study revealed that compounds 7d, 7f, 7g, and 7k could bind to the active site of E. coli DNA gyrase subunit B protein and form hydrogen bonding with crucial amino acid residues Arg136 in the active sites. Comprehensively, our study recommends that 7d, 7f, 7g, and 7k could be a promising lead for developing more efficient antimicrobial drug candidates and DNA gyrase inhibitors. [ABSTRACT FROM AUTHOR]

This article discusses the possibilities of two methods for monitoring Physical Vapor Deposition (PVD) process parameters: multi-grid probe, which makes it possible, in particular, to determine the energy distribution of ions of one- or two-component plasma and spectrum analyzer of the glow discharge plasma electromagnetic radiation signal based on the Prony–Fourier multichannel inductive spectral analysis sensor. The energy distribution curves of argon ions in the low-voltage operation mode of ion sources with closed electron current have been analyzed. With a decline in the discharge current, the average ion energy decreases, and the source efficiency (the ratio of the average ion energy W to the discharge voltage U) remains approximately at the same level of W/U ≈ 0.68, ..., 0.71 in the operating voltage range of the source. The spectrum analyzer system can obtain not only the spectra at the output of the sensor, but also the deconvolution of the spectrum of the electromagnetic radiation signal of the glow discharge plasma. The scheme of a spectrum analyzer is considered, which can be used both for monitoring and for controlling the processing process, including in automated PVD installations. [ABSTRACT FROM AUTHOR]

Single crystals of a new quaternary oxide, barium hexadecayttrium tetrasilicon tritriacontaoxide, BaY16Si4O33, were obtained from a melt-solidified sample prepared by heating a mixture of BaCO3, Y2O3, and SiO2 at 2073 K. X-ray crystal structure analysis revealed that Ba(SiO4)4 orthosilicate clusters in which a Ba atom is surrounded by four SiO4 tetrahedra were isolated in a framework composed of Y and O in the structure of BaY16Si4O33. The dielectric constant measured for polycrystalline ceramics of BaY16Si4O33 sintered at 1953 K was 13 (298 K, 1 MHz), and the thermal expansion coefficient was 8.70 × 10-6 K-1 (298-873 K), which are close to the values previously reported for Y2O3. [ABSTRACT FROM AUTHOR]