The electronic structure of Ni2P (10−10) has been investigated by photoemission spectroscopy (PES) utilizing synchrotron radiation. The surface which was cleaned by Ar+ ion sputtering (3 kV, 15 min) and annealing (400oC) gave a c (2×4) low-energy electron diffraction pattern. In the PES spectra measured for this surface, a Ni 3d-P 3p hybrid band (main band) and a satellite were observed at 0—4 eV and at 8 eV, respectively. Resonant PES (RPES) study showed that the satellite is associated with the photoemission process leading to a two-hole bound final state. The angle-resolved PES measurements showed that there were at least two surface states ; one was observed at about 0.4 eV around the Γ− point and the other was observed at about 0.6 eV along the boundary of the surface Brillouin zone along the  direction. The results of RPES measurements suggested that the latter state should have little contribution of the Ni 3d component.
We have developed a confocal 3D-XRF spectrometer in combination with polycapillary X-ray lenses and a laboratory X-ray source. The depth resolutions of the 3D-XRF configuration estimated by scanning of Au and Cr thin foils were approximately 50 μm for AuLα, and 100 μm for CrKα, respectively. The capacity of the depth-sensitive analysis of the confocal setup was investigated by scanning a thick plastic reference sample concluding trace metals of Ti, Cr, Co and Pb. The depth sensitivity in deeper region was significantly decreased than that in the surface region because of the absorption of X-ray irradiation and X-ray fluorescence in the material. The calculated LLD values of Cr at each depth were 9.4 mg/kg at 300 μm, 23 mg/kg at 500 μm, 38 mg/kg at 700 μm, 77 g/kg at 900 μm, and 110 mg/kg at 1100 μm, respectively. 3D elemental analysis with the confocal XRF setup was demonstrated for an electrical Cu cable covered with PVC. The 3D elemental images agreed well with the actual distributions of the sample. The confocal 3D-XRF has a great advantage for 3D elemental analysis as well as nondestructive depth analysis at ambient pressure.
CO and NO adsorption effects on the magnetism of 2 and 4 ML Fe thin films on Cu(001) were studied. The changes of magnetic structures were discussed in a relationship to crystalline structures of the films. The magnetic structure of the Fe(2 ML)/Cu(001) film was not affected by CO adsorption, but CO adsorption on Fe(4 ML)/Cu(001) caused a spin reorientation transition to in plane. Moreover, the magnetization was apparently reduced to the half of the initial value. The reason of the apparent reduction of the magnetization was studied by means of a depth resolved XMCD technique. The surface two layers of the film lose the magnetization, and only the bottom two layers keep the magnetization. These films were examined by EXAFS measurements to reveal a structural difference between the magnetically live layers and magnetically dead layers. Also, a NO adsorbed Fe 4 ML film has the in-plane easy axes of magnetization, and the magnetization of the topmost layer aligns in the opposite direction to the other layers. The antiferromagnetism in the surface layers has been caused by NO adsorption on the Fe/Cu(001) film.
The structure of Nb-doped anatase TiO2 (TNO) was calculated using density functional theory (DFT) -based first-principle method. In order to clarify the role of oxygen vacancies, periodic unit cells with several combinations of dopant atoms and oxygen vacancies were investigated. The same calculation scheme was adapted to W-doped anatase TiO2 (TWO), and Nb-doped rutile TiO2 for a comparison. The results showed that the possibility of three-body complex in TNO is rather small, compared to the case of TWO and Nb-doped rutile TiO2. In the latter cases, a strong energy stabilization was observed in a linear W-VO-W and a bent VO-Nb-VO structure, respectively. Feasibility of sufficient sampling of the two-body and three-body interactions was pointed out, and a computational strategy for the assessment of thermodynamical stabilities of the three-body complexes and the chemical potential of oxygen atoms were discussed.
Graphene can be formed on Si substrates by annealing a 3C-SiC thin film on Si substrate in UHV at the temperature of 1250oC or higher. In this graphene-on-silicon (GOS) method, graphene grows on three major low-index planes of Si(111), (110), and (100). By using SEM, AFM, EBSD, and TEM, we have investigated changes in the quality of SiC films during graphitization, and have confirmed impacts of the crystallographic orientation on the changes;the SiC thin film on the Si(100) substrate is of highest quality after graphitization. The number of graphene layers also depends on the orientation, which varies in the order of Si(110) > (100) > (111). In contrast, the quality of graphene, as judged by Raman-scattering spectroscopy, is not so much affected by the orientation, i.e. by the quality of the SiC thin film in its macroscopic level.
Several types of metal-polymer hybrid films were prepared by electroless plating of self-organized honeycomb-patterned polymer films. The polystyrene honeycomb film was fabricated by a template method of hexagonally ordered condensed water droplets, and composed of a micrometric porous array and nanometric pillar structures that hold top and bottom porous layers together. Chemical adhesion of palladium catalysts for nickel electroless plating was controlled by difference of wettability of the honeycomb structures. After electroless plating and peeling off the top layer of the honeycomb film, various kinds of the metal-polymer hybrid films such as metal-coated honeycomb-patterned polymer films, metal-coated pillar-structured polymer films, ring-like-structured metal in the honeycomb-patterned polymer film, ball-like-structured metal array in the honeycomb-patterned polymer film, and dome-like-structured metal in the pillar-structured polymer film were obtained.