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We have investigated the effect of the uniaxial strain on the binding energy of valence band top, Si 1s and Ge 2p core level by Hard X-ray Photoemission Spectroscopy (HXPES) with the high spatial resolution. By combining HXPES with the high spatial resolution using K-B mirrors and uniaxially strained SiGe samples fabricated by selective ion-implantation, we succeeded in observation of the effect of uniaxial strain on the valence band structure. We have found that the energy difference between Ge 2p and valence band top in the case of uniaxial strain is smaller than that in the case of biaxial strain.

Effect of substrate surface orientation on the properties of La2O3 MOS capacitors was investigated. The dielectric-thickness dependence on VFB indicated that the (110) sample contains smaller amount of fixed charge than the other samples of (100) and (111). The EOT after post-metallization annealing also varied with the orientation: larger value for (111) than the other. The x-ray photoemission spectroscopy revealed that the growth of SiO2-rich silicate phase of low permittivity depends on the orientation and can change EOT. The results suggest that the (110) is preferable for small EOT and adequate VFB value when the interface-state density is significantly reduced.

The electronic structures of Pt and Pt-Co nanoparticles with O2adsorption and O2/H2O co-adsorption were investigated by in situhard X-ray photoelectron spectroscopy (HAXPES) and in situhigh resolution fluorescence detection X-ray absorption spectroscopy (HERFD-XAS) to clarify the effects of water adsorption on fuel cell cathode catalysis surface. The experimental results suggest that under the pressure of 1 mbar, the adsorption of H2O hinders the successive O2adsorption on Pt surface, while under the pressure of 1 bar, the adsorption of H2O enhances the adsorption of O2on Pt surface. This water effect is found to be more significant on Pt surface than on Pt-Co surface. These results would be helpful to understand how the water affects the fuel cell performance and why Pt-Co nanoparticles show higher oxygen reduce reaction (ORR) activity than Pt nanoparticles.

Effect of substrate surface orientation on the properties of La2O3MOS capacitors was investigated. The dielectric-thickness dependence on VFBindicated that the (110) sample contains smaller amount of fixed charge than the other samples of (100) and (111). The EOT after post-metallization annealing also varied with the orientation: larger value for (111) than the other. The x-ray photoemission spectroscopy revealed that the growth of SiO2-rich silicate phase of low permittivity depends on the orientation and can change EOT. The results suggest that the (110) is preferable for small EOT and adequate VFBvalue when the interface-state density is significantly reduced.