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Aluminum nitride (AlN) is a wide bandgap material used in acoustic devices, piezo- micro-electromechanical system and is promising for other electronic applications. However, for most applications, the AlN crystalline quality obtained by PVD or MOCVD is insufficient, and suitable growth substrates providing an adapted lattice match and coefficient of thermal expansion are limited. Alternatively, monocrystalline AlN wafers are not yet available in 200/300 mm sizes and suffer from high costs and quality issues. Here, we propose a novel approach involving a two-dimensional transition metal dichalcogenide (TMD) material as a seed layer, which displays an excellent lattice matching with AlN (>98%) allowing a strong enhancement in the c axis texture of sputtered AlN layers on Si(100)/SiO2 thermal oxide (500 nm) substrates. We have successfully demonstrated an eightfold improvement of the AlN (002) rocking curve compared to reference samples grown on thermal SiO2, thus providing a relevant and cost-effective process for the large-scale deployment of high-quality III-N materials on silicon-based substrates. [ABSTRACT FROM AUTHOR]

De nos jours la lutte contre les punaises rouges, ravageurs du cotonnier, se resume en l'utilisation d'insecticides chimiques de synthese. Nombre de ces produits utilises sont persistants et leur grande toxicite sur la sante humaine et environnementale est preoccupante. Dans la recherche d'alternatives aux insecticides chimiques de synthese, ce present travail de recherche vise a evaluer le potentiel insecticide des emulsions aqueuses a base de l'huile essentielle de Cymbopogon schoenanthus (L.) contre Dysdercus voelkeri, un des redoutables ravageurs du cotonnier au Togo. Des emulsions aqueuses a differentes concentrations ont ete utilisees dans les traitements phytosanitaires sur culture cotonniere en comparaison avec des insecticides binaires vulgarises (lambdacyhalothrine/profenofos 15/300 [gha.sup.-1] et cypermethrine/acetamipride 36/8 [gha.sup.-1]). Les denombrements de D. voelkeri sur les plantes cibles de chaque parcelle elementaire ont montre que la dose la plus forte de l'emulsion (6%) et le temoin positif (insecticide vulgarise) ont ete plus efficaces avec des densites de populations faibles de punaises respectivement de 7,14 [+ or -] 1,46 et 4,86 [+ or -] 1,84 punaises/plant. Contrairement les autres doses (4 et 2%) d'emulsions a base de l'huile essentielle de C. schoenanthus ont eu dans leurs parcelles respectivement 39,57[+ or -]5,81 et 45,28[+ or -]3,92 punaises/plant et le temoin (55,71 [+ or -] 5,23 punaises/plant). L'analyse sanitaire des jeunes capsules tombees sous les cotonniers a revele que la dose la plus forte de l'emulsion (6%) et le temoin positif ont reduit respectivement les piqures des punaises de 71,40 et 72,33% par rapport au temoin. Les taux de reduction des piqures dans les parcelles a traitements de 4 et 2% de l'emulsion ont ete faibles avec des taux respectifs de 55,32% et 22,83%. Ces resultats revelent clairement que l'emulsion aqueuse formulee et testee dans l'etude peut reduire significativement les attaques de ces ravageurs. Cette etude montre la possibilite de l'utilisation de l'huile essentielle de C. schoenanthus comme matiere premiere dans la formulation de biopesticide comme alternative aux insecticides chimiques de synthese dans la lutte contre les punaises rouges du cotonnier au Togo. Mots cles: Cymbopogon schoenanthus, insecticide, emulsion aqueuse, Dysdercus voelkeri, cotonnier, capsules Currently, the fight against red bugs, a pest of the cotton plant, is limited to the use of synthetic chemical insecticides. Many of the products used are persistent and their high toxicity to human health and the environment is of concern. In the search for alternatives to synthetic chemical insecticides, the aim of this research work was to evaluate the insecticidal potential of aqueous emulsions based on the essential oil of Cymbopogon schoenanthus (L.) against Dysdercus voelkeri, one of the redoubtable pests of cotton plant in Togo. Aqueous emulsions at different concentrations were used in phytosanitary treatments on cotton crop compared to vulgarized binary insecticides (lambdacyhalothrin/profenofos 15/300 [gha.sup.-1] and cypermethrin/acetamiprid 36/8 [gha.sup.-1]). D. voelkeri counts on target plants of each elementary plot revealed that the highest dose of the emulsion (6%) of C. schoenanthus essential oil and the control (vulgarized insecticide) were more effective with low bug population densities of 7.14 [+ or -] 1.46 and 4.86 [+ or -] 1.84 bugs/plant, respectively. On the contrary, the other doses (4 and 2%) of emulsions based on C. schoenanthus essential oil had in their plots respectively 39.57 [+ or -] 5.81 and 45.28 [+ or -] 3.92 bugs/plant and the control (55.71 [+ or -] 5.23 bugs/plant). Health analysis of the young cotton bolls that fell under the cotton plants revealed that the highest dose of the emulsion (6%) and the control reduced stings by 71.40 and 72.33 % respectively, compared to the control. Stings reduction rates in plots with treatments of 4 and 2% of the emulsion were low with rates of 55.32 and 22.83 %, respectively. These results clearly show that the aqueous emulsion formulated and tested in the study can significantly reduce attacks of these pests. This study shows the possibility of using the essential oil of C. schoenanthus as a raw material in the formulation of biopesticide as an alternative to synthetic chemical insecticides in the control of cotton plant red bugs in Togo. Key words: Cymbopogon schoenanthus, insecticide, aqueous emulsion, Dysdercus voelkeri, cotton plant, bolls, INTRODUCTION Le coton-graine constitue dans la sous-region ouest africaine l'un des principaux produits de rente et occupe une place centrale dans l'economie de l'ensemble des pays producteurs. La production totale [...]

Two-dimensional (2D) metal nitrides are new emerging materials with potential applications in electronics, energy storage, or conversion efficiency. In this paper, we report the synthesis of molybdenum nitride by nitriding molybdenum disulfide (MoS2) via a 700 °C ammonia (NH3) reactive heat treatment. A well-controlled uniform MoS2 thin film was prepared by atomic layer deposition (ALD). The progressive MoS2 nitriding reaction has been demonstrated and monitored by in situ reflectance measurements. These results have been confirmed by Raman and x-ray photoelectron spectrometry. This method paves the way to a new potential route to the synthesis of Mo nitride obtained from a well-controlled uniform 2D-MoS2 thin film deposited by ALD. [ABSTRACT FROM AUTHOR]

The purpose of this pilot study was to investigate the effects of the transfusion of one erythrocyte concentrate on the number of circulating red blood cell extracellular vesicles (RBC‐EVs) and their clearance time. Six, healthy volunteers donated their blood and were transfused with their RBC concentrate after 35–36 days of storage. One K2EDTA and one serum sample were collected before donation, at four timepoints after donation and at another six timepoints after transfusion. RBC‐EVs were analyzed on a Cytek Aurora flow cytometer. A highly significant increase (p < 0.001) of RBC‐EVs from an average of 60.1 ± 19.8 (103/μL) at baseline to 179.3 ± 84.7 (103/μL) in the first 1–3 h after transfusion could be observed. Individual differences in the response to transfusion became apparent with one volunteer showing no increase and another an increased concentration at one timepoint after donation due to an influenza infection. We concluded that in an individualized passport approach, increased RBC‐EVs might be considered as additional evidence when interpreting suspicious Athletes Biological Passport (ABPs) but for this additional research related to sample collection and transport processes as well as method development and harmonization would be necessary. [ABSTRACT FROM AUTHOR]

An electrical analysis of mechanical stress induced by shallow trench isolation (STI) on MOSFETs of advanced 0.13 [mu]m bulk and silicon-on-insulator (SOI) technologies is presented. It is shown that the observed higher pMOS drain current shift is related to the process, and may be explained by doping amorphization and recrystallization effects, and not by a piezoresistive coefficient difference as usually assumed.

The sensitivity of SOI technologies to transient irradiations (both dose rate and heavy ions) is analyzed as a function of the technology architecture with experiments and simulations. Two main parameters are considered. First, the thickness of the silicon film, which determines the fully or partially depleted state of SOI devices. This parameter strongly influences the parasitic bipolar, which amplifies the radiation-generated charge. In particular, fully depleted devices show a low bipolar gain due to a high-impact ionization. Secondly, the doping profile in the drain region, which varies with process optimization. The trend is to use shallow junctions to reduce short-channel effects in partially depleted devices. Shallow-drain junctions in partially depleted devices contribute to increases in drain-region sensitivity. As a result, fully depleted architectures are more adapted to reduce the radiation sensitivity of future SOI technologies, because it both reduces the bipolar amplification and the sensitivity of the drain region. Index Terms--Critical charge, cross section, current gain, device simulation, doping profile, dose rate, fully depleted, heavy ion, impact ionization, lightly doped drain, linear energy transfer, MOS transistor, parasitic bipolar transistor, partially depleted, radiation, shallow junction, SOI, SRAM, transient response.

A new study investigates the effect of nonuniform interface trap distributions on capacitance-voltage characteristics of 6H-SiC metal-oxide-semiconductor capacitors.

Research was conducted to examine the impact of incomplete ionization of dopants on the capacitance-voltage characteristics in 6H-SiC metal-oxide semiconductor capacitors. The study was based on the one-dimensional numerical solving of Poisson's equation via the finite-difference method with a nonuniform mesh size. Results are in excellent agreement with the first analytical results obtained in the case of indium impurities in silicon.

A latch effect induced by total dose irradiation is observed in short channel SOI transistors. This effect appears on NMOS transistors with either a fully or a partially depleted structure. It is characterized by a hysteresis behavior of the Id-Vg characteristics at high drain bias for a given 'critical' dose. Above this dose, we still observe a limited leakage current at low drain bias (0.1 V), but a high conduction current at high drain bias (2 V) as the transistor should be in the off-state. The critical dose above which the latch appears strongly depends on gate length, transistor structure (fully or partially depleted), buried oxide thickness and supply voltage. Two-dimensional (2D) numerical simulations indicate that the parasitic conduction is due to the latch of the back gate transistor triggered by charge trapping in the buried oxide. To avoid the latch induced by the floating body effect, different techniques can be used: doping engineering, body contacts, etc. The study of the main parameters influencing the latch (gate length, supply voltage) shows that the scaling of technologies does not necessarily imply an increased latch sensitivity. Some technological parameters like the buried oxide hardness and thickness can be used to avoid latch, even at high cumulated dose, on highly integrated SOI technologies.

Silicon carbide bipolar diodes were fabricated by nitrogen implantation, annealed at 1100 degrees C, passivated with a deposited oxide and characterized. The quality of the junction was analyzed using capacitance and current voltage measurements. Three peaks were observed using admittance spectroscopy, with two corresponding to nitrogen and aluminium shallow levels. The third peak was studied in depth using deep level transient spectroscopy.

The characteristics of bipolar n+pp+ diodes manufactured through nitrogen implantation and passivated with a deposited oxide were investigated. Current-voltage measurements in a broad temperature range were examined. Also, the optical beam induced current method was employed to represent the depleted zone at the surface around a reverse-biased device. Findings indicated that the presence of interface states or oxide traps induced a decrease of the current by trapping the carriers. Moreover, the presence of mobile charges induced a small increase of the current.

A method combining charge pumping and current-voltage measurements is presented for determining the surface potential versus gate voltage relationship in irradiated MOS transistors. This technique uses parameter optimization and simple numerical equations. It can be applied even for a high interface state density and for a non-uniform distribution in the silicon bandgap. This makes the method attractive for all studies concerning interface trap characterization or accurate modeling of MOS transistors in subthreshold regime. In this study, this new approach is applied to n-channel transistors irradiated up to 10 Mrad (Si[O.sub.2]).

We present experimental measurements of charge collection spectroscopy from high energy ion strikes in submicron CMOS/SOI devices. Due to the specific structure of SOI technology, with symmetrical source and drain junctions, a direct equivalence between upset mechanism and charge collection is established. The bipolar mechanism, responsible for the amplification of the deposited charge is discussed based on 2D device simulations. based on the experimental data we determine qualitatively the influence of transistor geometry on the bipolar gain. Finally the limits of the usual SEU concepts (LET threshold and cross section) are discussed for scaled devices.