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High-throughput and combinatorial materials science methods were used to investigate the dependence of the work function in the Ni–Si system on the B content (0–30 at. %). Alloying of NiSi is used to adapt its properties to suit the needs as a gate electrode material. Thin-film materials libraries were fabricated and investigated with respect to their structural and electrical properties. Further the work function values of selected samples in the region of interest were analyzed. The results show that the work function can be adjusted between 4.86 eV (B = 4.2 at. %) and 5.16 eV (B = 29.2 at. %) for (NiSi)Bx.

International audience; Transition metal nitrides (TMN) form a class of materials with unique physical and chemical properties. Among them, molybdenum nitrides are mainly used as high-performance magnets or catalysts for a wide range of reactions. This work aims at developing innovative syntheses to prepare nanostructured TMN from metallic clusters for heterogeneous catalysis. The use of a nanoscale precursor such as (TBA)(2) Mo6Br14 (TBA = tetrabutylammonium = (C4H9)(4)N+) enables us to reach different molybdenum nitride compositions (Mo2N, Mo5N6) by thermal reaction under ammonia at relatively low temperatures. Such a novel synthetic approach highlights the prime importance of the starting material to stabilize specific stoichiometries. The impact of this new synthetic route is characterized by several techniques including electron probe microanalysis and high-resolution transmission microscopy. Moreover,catalytic properties of these potential cost-effective catalysts are investigated for the Water-Gas Shift Reaction.

With the aim of producing functional materials based on earth-abundant elements, we examined the synthesis of the ternary type-I clathrates A8AlxSi46−x (A = Na and K). The type-I Si clathrate K7.9(1)Al7.1(1)Si38.9(4), having a lattice parameter of 10.434(1) A, was successfully synthesized via the direct reaction of K, Al, and Si by optimization of both the synthesis temperature and the molar ratios among the raw ingredients. K8Al7Si39 exhibited metallic conduction: its electrical resistivity increased with increasing temperature. The high pressure synthesis of Na8AlxSi46−x was also examined, using a belt-type apparatus and employing a mixture of NaSi, Al, and Si as the reagents. In this manner, the type-I Si clathrate Na8.7(9)Al0.5(1)Si45(2), having a lattice parameter of 10.211(1) A, was synthesized at 5.5 GPa and 1570 K.

A pilot study for a quantitative surface analysis of multi-element alloy films has been performed by the Surface Analysis Working Group (SAWG) of the Consultative Committee for Amount of Substance (CCQM). The aim of this pilot study is to evaluate a protocol for a key comparison to demonstrate the equivalence of measures by National Metrology Institutes (NMIs) and Designated Institutes (DI) for the mole fractions of multi-element alloy films. A Cu(In,Ga)Se2 (CIGS) film with non-uniform depth distribution was chosen as a representative multi-element alloy film. The mole fractions of the reference and the test CIGS films were certified by isotope dilution—inductively coupled plasma/mass spectrometry. A total number counting (TNC) method was used as a method to determine the signal intensities of the constituent elements acquired in SIMS, XPS and AES depth profiling. TNC method is comparable with the certification process because the certified mole fractions are the average values of the films.The mole fractions of the CIGS films were measured by Secondary Ion Mass Spectrometry (SIMS), Auger Electron Spectroscopy (AES), X-ray Photoelectron Spectroscopy (XPS), X-Ray Fluorescence (XRF) Analysis and Electron Probe Micro Analysis (EPMA) with Energy Dispersive X-ray Spectrometry (EDX). Fifteen laboratories from eight NMIs, one DI, and six non-NMIs participated in this pilot study.The average mole fractions of the reported data showed relative standard deviations from 5.5 % to 6.8 % and average relative expanded uncertainties in the range from 4.52 % to 4.86 % for the four test CIGS specimens. These values are smaller than those in the key comparison CCQM-K67 for the measurement of mole fractions of Fe-Ni alloy films. As one result it can be stated that SIMS, XPS and AES protocols relying on the quantification of CIGS films using the TNC method are mature to be used in a CCQM key comparison. Main text. To reach the main text of this paper, click on Final Report. The final report has been peer-reviewed and approved for publication by CCQM.

The radiative Auger satellite peaks of Al Kα for aluminum metal and aluminum oxide were measured over a small area using an electron probe microanalyzer (EPMA). The oscillation was found to be similar to the extended X-ray absorption fine structure (EXAFS) in the EPMA spectra, oscillation which was recently discovered by Hayashi et al. (1997) in the X-ray fluorescence (XRF) spectra. The measured EXAFS spectra with EPMA are in good agreement with those by Hayashi et al., but here the oscillation structure could be obtained in a few minutes over a small area by using EPMA.

Superconducting properties of the polycrystalline Zr2Ru3Si4 were investigated by the electrical resistivity, magnetization and specific heat. By these measurements, bulk superconductivity with transition temperature Tc = 5.5 K was confirmed. Moreover, Zr2Ru3Si4 was found to be a type-II and intermediate-coupling superconductor. Interestingly, the electronic specific heat shows a deviation from a one-gap s-wave model and Hc2(T) shows unusual positive curvature in the vicinity of Tc. The first principle's calculation shows the existence of plural anisotropic Fermi surfaces. These results suggest that Zr2Ru3Si4 is not an isotropic single-gap superconductor, but possibly a multi-gap or an anisotropic gap superconductor., Comment: 13 pages, 6 figures

Measurements of electrical resistivity ρ, magnetization M and specific heat C have revealed that SrPt2Sb2 is a type-II superconducting material with a superconducting critical temperature (Tc) of 2.1 K. The electronic specific heat coefficient γ and the ratio ΔC(Tc)/γTc are 9.2(1) mJ mol−1 K−2 and 1.29, respectively. The temperature dependence of ρ exhibits anomalies around 270 K. Synchrotron x-ray diffraction patterns at 295 and 134 K clearly indicate that SrPt2Sb2 undergoes a structural phase transition in the temperature range from 134 to 295 K, suggesting that the anomalies observed in ρ around 270 K are related to a structural phase transition.