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The cross-sections of deuteron-induced nuclear reactions suitable for ion beam analysis, measured in different laboratories, are often significantly different. In the present work, differential cross-sections of 27 Al(d,p) and 27 Al(d,α) reactions were measured, and the cross sections benchmarked with thick target spectra obtained from pure aluminium for the first time in two independent laboratories. The 27 Al(d,p) and (d,alpha) differential cross-sections were measured between 1.4 and 2 MeV at scattering angles of 165°, 150°, and 135° in the VDGT laboratory in Tehran (Iran), and the same measurements for detector angle of 150° were repeated from scratch, including target making, with independent equipment on the SAFIR platform at INSP in Paris (France). The results of these two measurements at 150° are in good agreement, and for the first time a fitted function is proposed to describe the Al-cross sections for which no suitable theoretical expression exists. The obtained differential cross-sections were validated through benchmarking, by fitting with SIMNRA deuteron-induced particle spectra obtained from a high purity bulk Al target at both labs for deuteron incident energies between 1.6 and 2 MeV. The thick target spectra are well-reproduced. The evaluated and benchmarked cross sections have been uploaded to the ion beam analysis nuclear data library database (www-nds.iaea.org/ibandl/).

International audience; Ta3N5 belongs to the group of transition metal nitrides with the cation in a high oxidation state. These are typically challenging to synthesize owing to the low reactivity of nitrogen. This applies similarly to Ta3N5 that crystallizes only in the presence of oxygen during synthesis. Typical preparation methods are ammonolysis of oxidized Ta or magnetron sputtering of a Ta target in an atmosphere of Ar, N2 and O2. However, the material typically obtained by either synthesis method is of varying degrees of crystallinity and the key parameter affecting the crystallinity remains elusive. In this study, we examine the role of oxygen for the crystallinity of Ta3N5 samples by studying. Thin film samples prepared by magnetron sputtering reveal that oxygen is indeed the central driver for Ta3N5 crystallinity. While little oxygen in the films yields the metallic δ-TaN phase, excess oxygen results in low crystallinity Ta3N5 or Ta-O-N films. Ta3N5 samples with a high degree of crystallinity are obtained by limiting the oxygen supply to the sample during the deposition. A comparison with other studies suggests a fundamental oxygen incorporation limit above which the crystallinity of Ta3N5 is compromised. The most crystalline sample from this study contains 4.4 at.% of oxygen. It is grown onto a Si(100) substrate, covered with a 30 nm-thick metallic diffusion layer. For this sample, we observe Ta3N5 grains between 80 and 120 nm in size.

A study was carried out for the measurement of ultrathin SiO on (100) and (111) orientation silicon wafer in the thickness range 1.5-8 nm. XPS, medium-energy ion scattering spectrometry (MEIS), nuclear reaction analysis (NRA), RBS, elastic backscattering spectrometry (EBS), SIMS, ellipsometry, gazing-incidence x-ray reflectometry (GIXRR), neutron reflectometry and transmission electron microscopy (TEM) were used for the measurements. Water and carbonaceous contamination about 1 nm were observed by ellipsometry and adsorbed oxygen mainly from water at thickness of 0.5 nm were seen by MEIS, NRA, RBS and GIXRR. The different uncertainty of the techniques for the scaling constant were also discussed.

China is becoming the largest construction site in the world. Along with the appearance of a large number of fiercely competitive construction companies and the introduction of new construction techniques and materials, personal injury and fatal accidents in construction sites have continued to occur. However, the law regarding construction safety is also changing and improving. This paper on the construction safety legislative framework was prepared with the support of the Ministry of Construction and the State Administration of Working Safety in China. It is based on a comprehensive literature review and in-depth interviews with legislators, government officials and other participants in the construction process. A clear picture of the current situation relating to construction safety legislation in China is presented. After a brief review of the history of construction safety, the newly formed legal framework is described. Several major challenges have been identified and discussed, for example insufficient regulations and codes, poor coordination within and between the ministries and commissions, pervasive corruption. Suggestions are made for the promotion of construction safety in China, including the improvement of the legislative system based on the three principal laws, and the requirement that owners should bear legal responsibilities.

The oxygen exchange reactions can give valuable information concerning the oxidation mechanisms since they can be intermediate reactions. During dry thermal oxidation of silicon there are at least two different oxygen exchange reactions: oxygen exchange between oxygen molecules (O2 ↔ O2, catalyzed by the SiO2) and oxygen exchange between oxygen from the gas phase and the oxygen in SiO2 (O2 ↔ SiO2). The O2 ↔ SiO2 exchange takes place at the surface and more surprisingly also at the SiO2/Si interface. It has been shown that the oxygen exchange rate at the Si/SiO2 interface is at least 25% of the oxygen uptake rate, requiring a movement of oxygen both from the surface to the interface and from the interface to the surface. In this study, we evaluate the oxygen exchange for different pressures and temperatures. The amount exchanged depends marginally on these parameters and can probably be taken as a measure of the thickness of the reacting layer. The chemistry of this reacting layer plays a pronounced role ...

The modification by postoxidation NO treatments of the Si/SiO2 interface in thermally grown Si(100)/SiO2 layers has been studied by nuclear reaction analysis and electron paramagnetic resonance spectroscopy. Our results demonstrate a selective incorporation of NO molecules at the Si/SiO2 interface and a drastic reduction in the interface defect density. In this new configuration, the Pb center density, which is typically 2×1012 cm−2 in the as oxidized samples, is reduced to below 1011 cm−2 without any hydrogen passivation. The thermal treatment in NO atmospheres opens the perspective for the formation of hydrogen free low defect Si(100)/SiOxNy interfaces conserving the qualities of the SiO2 dielectric.

At the present time there is more construction being carried out in China than in any other single country in the world. With a population in excess of one billion and a rapidly expanding economy, China represents a huge, but difficult, potential market for civil engineering consultants and contractors. One of the major constraints to active involvement in China is a general lack of awareness of the country and the opportunities there. The aim of this paper is to illustrate the extent of current and planned construction projects in China and to describe the structure and development of the Chinese construction industry. (A)

The growth mechanisms of amorphous carbon (a-C:H) thin films obtained by the decomposition of methane gas in a multipolar plasma set up were studied using 13C as a tracer. Hydrogenated carbon films first grown in a methane plasma with natural isotopic composition (12C) were further grown in highly enriched 13C methane discharge (experiments were also carried out with the reverse order). 13C profiles were obtained by resonant nuclear reaction depth profiling using the narrow (FWHM

International audience; Ion beam analysis (IBA) methods always rely on available differential cross-section data to obtain quantitative results about composition and structure of the near-surface layer of a sample. In order to meet the nuclear data needs of the IBA community, the Coordinated Research Project (CRP) ``Development of a Reference Database for Ion Beam Analysis'' was initiated by the IAEA in 2005 and will be concluded in 2010. A summary of the results of this IAEA Coordinated Research Project activity is presented, problems still existing in the field are discussed, and ways to further develop nuclear data for IBA are indicated.

1st International Conference of the Asian-Union-of-Magnetics-Societies (AUMS), Korean Magnet Soc, Jeju Isl, SOUTH KOREA, DEC 05-08, 2010; International audience; The magnetic properties of low temperature MBE grown Ga0.90Mn0.10As1 - yPy films with 00.15 it changes to impurity band conduction (IBC). In the IBC regime the main magnetic properties are profoundly modified: the saturation magnetization decreases from typically 50 emu/cm(3) to 35 emu/cm(3), the critical temperature drops sharply from 130 K to 45 K and the uniaxial magnetic anisotropy spectroscopy is strongly reduced. (C) 2011 Elsevier B.V. All rights reserved.

The oxygen plasma treatment of chemical-vapour-deposited Si 3 N 4 thin films at floating potential and low T (less than 600 °C) leads to the growth of a silicon oxide surface layer and to a decrease of the nitrogen content of the samples. Nuclear reaction analysis was used to study the composition of the films, the oxide growth kinetics and the loss of nitrogen atoms. After an initial transient oxidation regime, parabolic growth laws were found, indicating that the rate-limiting step in the oxide formation is a diffusion process and not a surface reaction. In the low temperature regime the oxide growth rate and the activation energy were found to be similar to those obtained during the plasma oxidation of bare silicon substrates. 18 O-enriched plasmas were used to study the nitride transformation, and the 18 O depth distribution was determined by resonance depth profiling. The 18 O atoms were found at the surface of the sample, forming a pure SiO 2 layer on the underlying Si 3 N 4 . The absence of a large mixing at the oxide-nitride interface indicates that the oxide growth occurs by a layer-by-layer oxidation process and not by the formation of an oxynitride compound of varying composition with depth.

During dry thermal oxidation of silicon oxygen exchange reactions may occur between oxygen molecules (O2↔O2, catalyzed by the SiO2) or between oxygen from the gas phase and the oxygen in SiO2 (O2↔SiO2), both at the surface and at the Si–SiO2 interface. We found that the oxygen exchange rate at the Si–SiO2 interface is at least 25% of the oxygen uptake rate, requiring the movement of oxygen both from the surface to the interface, and from the interface to the surface. The oxygen exchange at the interface is further evidence in favor of the presence of a reactive interfacial layer between the growing oxide and the silicon substrate.

We have studied the excitation curve of the 27Al(p, γ)28Si narrow resonance (ΓR = 105 eV) at 992 keV in random and axial channelling geometry on a clean (110) Al single crystal under UHV conditions. The results are compared to semi-analytical calculations and to Monte Carlo simulations. The comparison for the aligned case provides the impact parameter dependence of the mean inelastic energy transfer. At low impact parameter (~ 0.15 A) with respect to the strings, these transfers are ~ 8 times higher than in random conditions. The mean energy transfer to inner-shell Al electrons is shown to be proportional to the corresponding electronic density sampled by the ions, in good agreement with theoretical impact parameter treatments of the energy loss.

1. 1. Staining techniques used to reveal check ring patterns in otoliths owed their effect to the dissolution of otolith material caused by the low pH of the stain. 2. 2. Stains with higher pH values did not etch otoliths, but showed variable staining intensities in different parts of the otolith as well as between parts of micro- and macroincrements. 3. 3. Acid dissolution of sections of otoliths left deposits of protein with patterns similar to observed micro- and macroincrements. 4. 4. Comparisons of the patterns of low and high pH staining effects suggested that two acid insoluble matrix proteins may be present, one with S-C-N groupings similar to keratin; and that a third acid soluble protein is associated with the dark band of the microincrement resulting in etched grooves at the point where the microincrements become more narrow.

Amorphous aluminum oxide (Al2O3) thin films codoped with Tm3+ and Er3+ have been prepared by pulsed laser deposition. A broad emission band with a full-width half maximum (FWHM) up to 230 nm was observed in Tm-Er codoped film. The spectrum shows two peaks located at 1540 nm corresponding to Er3+ emission and 1640 nm due to Tm3+ emission. The luminescence intensity dependence on the annealing temperature was investigated. It is shown that the annealing temperature and energy transfer between Tm3+ and Er3+ ions play an important role in the definition of the luminescent response.

The Rutherford backscattering spectroscopy (RBS) surface height of a pure bulk material can be used as an absolute standard value to calibrate the detector solid angle. This work presents the results of an international collaboration started at the beginning of 1998 to define the surface height of the RBS spectrum (H0) of Si, amorphized by ion implantation to avoid channeling. The analyses were performed with 1–3 MeV He beams and 170° scattering angle. The detector solid angle was estimated in the different laboratories either by geometrical measurement or by a calibrated standard. The agreement of the experimental H0 values is of the order ±2%, the claimed accuracy for RBS. The results are also consistent at 2% level with both the stopping power measurements of Konac et al. (1998), and the measurements of Lennard et al. (1999).

International audience; We report on our multi–pronged approach to understand the structural and electrical properties of an InAl(Ga)N(33nm barrier)/Al(Ga)N(1nm interlayer)/GaN(3μm)/ AlN(100nm)/Al2O3 high electron mobility transistor (HEMT) heterostructure grown by metal organic vapor phase epitaxy (MOVPE). In particular we reveal and discuss the role of unintentional Ga incorporation in the barrier and also in the interlayer. The observation of unintentional Ga incorporation by using energy dispersive X–ray spectroscopy analysis in a scanning transmission electron microscope is supported with results obtained for samples with a range of AlN interlayer thicknesses grown under both the showerhead as well as the horizontal type MOVPE reactors. Poisson–Schrödinger simulations show that for high Ga incorporation in the Al(Ga)N interlayer, an additional triangular well with very small depth may be exhibited in parallel to the main 2–DEG channel. The presence of this additional channel may cause parasitic conduction and severe issues in device characteristics and processing. Producing a HEMT structure with InAlGaN as the barrier and AlGaN as the interlayer with appropriate alloy composition may be a possible route to optimization, as it might be difficult to avoid Ga incorporation while continuously depositing the layers using the MOVPE growth method. Our present work shows the necessity of a multicharacterization approach to correlate structural and electrical properties to understand device structures and their performance.