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We report the investigation of the adsorption behavior of sulfur-containing (CH3)2S molecule on Ag(1 1 1) surface. Submonolayer and multilayer adsorption phases under UHV and liquid N2 temperature conditions were studied by means of polarization dependent Sulfur-K near-edge X-ray absorption fine structure (NEXAFS) and X-ray photoelectron spectroscopy (XPS) techniques. The (CH3)2S molecule for submonolayer phase adsorbs molecularly on Ag(1 1 1) surface at 86 K. The sulfur and two methyl groups of the (CH3)2S molecule have some interaction with surface Ag atoms. The orientation angle of two S–C bonds is estimated to be 23 ± 5° from the surface. [Copyright &y& Elsevier]

Abstract: Carbon-based materials, such as carbon nanotubes and graphene nanoribbons, have been studied as interconnect materials because of their lower resistivity, higher thermal conductivity, and intrinsically higher current carrying capacity compared to Cu. We have succeeded in growing networked-nanographite (NNG) films on dielectric layers without any metal catalysts, and fabricated NNG wires as the first step toward multi-layer graphene interconnects. In this study, we investigated the electrical properties and reliability, such as current tolerance and thermal stability, of these NNG wires. In addition, we investigated the mechanism of resistivity decreases in NNG. Our results show that the NNG wires can sustain a higher current density than Cu wires. However, their resistivity gradually decreases due to thermal stress. Raman and X-ray photoelectron spectroscopy revealed that the decrease in resistivity can be attributed to an increase in sp2 bonding corresponding to the formation of a graphene sheet. It is important to clarify the mechanism of the decrease in resistivity, not only to improve thermal stability but also to obtain lower resistivity in carbon interconnects. [Copyright &y& Elsevier]

Abstract: The Lα and Lβ X-ray emission spectra in the elements between Pd (Z=46) and Sb (Z=51) were measured using a high-resolution double-crystal vacuum spectrometer. The relative intensities of satellite structures, which originate in L 1 L 3 M 4,5 Coster–Kronig transitions, were estimated to that of each diagram line, and compared with calculated values. According to the work of Chen et al. [1977a. Theoretical L-shell Coster–Kronig energies 11⩽Z⩽103. At. Data Nucl. Data Tables 19, 97–151], Salgueiro et al. [1987. J. Phys. (Paris) 48 Colloq. C9, 609] and Vlaicu et al. [1998. Investigation of the 74W L emission spectra and satellites. Phys. Rev. A 58, 3544] L 1 L 3 M 4 Coster–Kronig transition is forbidden for 50⩽Z⩽77, and L 1 L 3 M 5 Coster–Kronig transition is forbidden for 50⩽Z⩽73. The results suggest that L 1 L 3 M 4,5 Coster–Kronig transitions may be allowed even for Sn (Z=50) and Sb (Z=51). [Copyright &y& Elsevier]

Abstract: The temperature-induced mixed valence transition in EuNi2(Si0.20Ge0.80)2 has been investigated by hard X-ray (5940eV) photoemission spectroscopy (HX-PES) for fractured surfaces, with a probing depth larger than 5nm. The Eu 3d core-level states are studied below and above the critical valence transition temperature, T v =80K. The HX-PES spectra at 40 and 120K show the mixed valence transition, with clear changes in the divalent and trivalent Eu 3d chemically shifted features. The Eu 3d HX-PES spectra indicate a mean valence of 2.70±0.03 at 40K which changes to 2.40±0.03 at 120K, in good accordance with the results of bulk EuIII-edge X-ray absorption spectroscopy measurements. [Copyright &y& Elsevier]