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[en] It is proposed that the Poole–Frenkel effect be applied to predict radiation-induced charge accumulation in thermal silicon dioxide. Various conduction mechanisms of thermal silicon dioxide are considered, the conditions of the appearance of the Poole–Frenkel effect in it are determined, and the characteristics of donor centers participating in Poole–Frenkel electrical conductivity are calculated. A donor center level at an energy of 2.34 eV below the conduction-band bottom is determined and the concentration of ionized donor centers of 1.0 × 109 cm–3 at 400 K and a field strength of 10 MV/cm is found. It is concluded that the Poole–Frenkel effect can be applied not for prediction of the absolute value of the radiation-induced charge but for comparison of the samples in terms of the ability to accumulate it.
[en] Avalanche photodiodes used in photosensitive devices with internal gain suffer some limitations due to their doping profiles and the reproducibility of their internal gain. Experiments were made on devices using very thin layers of SiO2. The basic structure being a MOS capacitance, it was shown that such a structure provides an internal gain when minority carriers are injected within the deep depletion layer just beneath the thin oxide in the silicon. Experimal results obtained on devices built using either aluminum and chromium electrodes are presented
[fr]Les photodiodes a avalanche utilisees dans les dispositifs photosensibles a gain interne souffrent de certaines limitations dues a leurs profils de dopage et a la reproductibilite de leur gain interne. Les experiences ont ete realisees sur des dispositifs utilisant de tres fines couches de SiO2. La structure de base etant une structure MOS, on a montre que le gain interne est obtenu quand les porteurs minoritaires sont injectes dans la couche profonde appauvrie au-dessous de la couche mince d'oxyde dans le silicium. On presente les resultats obtenus pour des dispositifs construits soit avec electrodes de chrome, soit avec electrodes d'aluminium
[en] We compiled a catalogue of 191 stellar objects showing SiO maser or thermal emission in at least one transition. These are 128 M-Supergiants and Mira variables, 29 IRC- and AFGL-sources, 32 OH/IR stars, the star-forming region Orion KL, and the symbiotic star H1-36. For each transition individual references are given. Special observational set-ups as polarization or VLBI measurements or monitor programs are noted
[en] The transport phenomenon involving a thorough mixture of a base fluid and any two different types of nanoparticles (i.e. hybrid nanofluid) has attracted the attention of scientists to deliberate on the significance and performance of such fluid using two different types of thermo-physical models (i.e. type I and type II). This study examines the dynamics of hybrid nanofluids using type I and type II hybrid models with major emphasis on the difference. Also, this report unravels the significance of suction and dual stretching on the boundary layer flow of hybrid nanofluids. The governing equation that model the dynamics was modeled, non-dimenzionalized, parameterized, and solved numerically. It is concluded that both type I and type II models of viscosity should not be used for volume fraction ϕ 1 + ϕ 2 > 0.02 as both models are found to be the same, accurate but limited. The stretching ratio has dual effects on the velocity in both horizontal directions and temperature distribution decreases with stretching rate. Local skin friction coefficients and temperature distribution are decreasing properties of suction. In the case of various water-based conveying various nanoparticles (seven different hybrid nanofluids), optimal Nusselt number is ascertained at a larger value of stretching ratio and suction in the dynamics of water conveying (less dense nanoparticles) multiple wall CNT and silicon dioxide. (paper)
[en] The IRAS source, 19312+1950, exhibits SiO maser emission, which is predominantly detected in evolved stars enshrouded by a cold molecular envelope. In fact, the majority of the observational properties of IRAS 19312+1950 are consistent with the nature of an asymptotic giant branch (AGB) star or post-AGB star. Interestingly, however, some of the observational properties cannot be readily explained within the standard scheme of stellar evolution, and those are rather reminiscent of young stellar objects. In the present research, we considered the evolutionary status of IRAS 19312+1950 as revealed by the very long baseline interferometry and MERLIN observations in SiO, H2O, and OH maser lines. The double-peaked profile of the 22 GHz H2O maser line is clearly detected, with the emission regions of its redshifted and blueshifted components separately located, leaving a space of about 10.9 mas between them. The kinematic properties of the H2O maser emission region appear to be more consistent with a bipolar flow rather than other interpretations such as the Keplerian rotation of a disk. The redshifted component of the SiO maser emission, which exhibits a double-peak profile in previous single-dish observations, is clearly detected in the present interferometry, while the 1612 MHz OH maser line exhibits a complicated line profile consisting of a single strong peak and many weak, high-velocity spikes. The structure of the OH maser emission region is partially resolved, and the kinematic properties of the OH maser emission region are observations reminiscent of a spherically expanding shell, even though the evidence is scant. Collectively, the maser observations described here provide additional support for the evolved star hypothesis for IRAS 19312+1950.
[en] Two methods are proposed to fabricate stacked ruthenium (Ru) nanocrystals (NCs): rapid thermal annealing (RTA) for the whole gate stacks, and RTA before each SiO2 layer deposition. The size and aerial density of Ru NCs are 2-4 nm and 3 x 1012 cm-2 for the former method, compared to 3-7 nm and 2 x1012 cm-2 for the latter. Because of the higher surface trap density and more uniform electron tunneling path between upper and lower Ru NCs, a 5.2 V memory window and 1 V after a period of 10 years are observed in metal oxide semiconductor (MOS) capacitors fabricated by the former method, which are much better than 4.6 V and no window remaining after one year observed in the latter. The former method is compatible with conventional CMOS technology.
[en] This paper introduces major characteristics of the single event latchup (SEL) in CMOS devices. We accomplish SEL tests for CPU and SRAM devices through the simulation by a pulse laser. The laser simulation results give the energy threshold for samples to undergo SEL. SEL current pulses are measured for CMOS devices in the latchup state, the sensitive areas in the devices are acquired, the major traits, causing large scale circuits to undergo SEL, are summarized, and the test equivalence between a pulse laser and ions is also analyzed.
[en] We review the construction of supersymmetric extension of the n-particle Euler–Calogero–Moser model within the Hamiltonian approach . The main feature of the proposed supersymmetrization method is that it is automatically adapted for a model with an arbitrary even number of supersymmetries. It is shown that the number of fermions that must be used in this construction is . We demonstrate that the resulting supersymmetric system is dynamically invariant with respect to the superconformal group and give the explicit realization of its generators in terms of the conserved currents. For the simplest case of the supersymmetric n-particle Euler–Calogero–Moser model we provide its description in superspace by using the corresponding constrained superfields. (paper)