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Teraoka, Yuden; Tode, Mayumi*; Harries, J.; Yoshigoe, Akitaka
Denki Gakkai Rombunshi, C, 134(4), p.473 - 478, 2014/04
Hashinokuchi, Michihiro*; Tode, Mayumi*; Yoshigoe, Akitaka; Teraoka, Yuden; Okada, Michio*
Applied Surface Science, 276, p.276 - 283, 2013/07
Times Cited Count:4 Percentile:19.06(Chemistry, Physical)Yokota, Kumiko*; Tagawa, Masahito*; Matsumoto, Koji*; Furuyama, Yuichi*; Kitamura, Akira*; Kanda, Kazuhiro*; Tode, Mayumi; Yoshigoe, Akitaka; Teraoka, Yuden
Protection of Materials and Structures from the Space Environment; Astrophysics and Space Science Proceedings, Vol.32, p.531 - 539, 2012/08
Harries, J.; Teraoka, Yuden; Tode, Mayumi; Yoshigoe, Akitaka
Applied Physics Express, 5(3), p.031802_1 - 031802_3, 2012/03
Times Cited Count:0 Percentile:0.00(Physics, Applied)Kanda, Kazuhiro*; Yokota, Kumiko*; Tagawa, Masahito*; Tode, Mayumi; Teraoka, Yuden; Matsui, Shinji*
Japanese Journal of Applied Physics, 50(5), p.055801_1 - 055801_3, 2011/05
Recently, the irradiation of soft X-ray synchrotron radiation (SR) to highly-hydrogenated diamond-like-carbon (H-DLC) films in vacuum results in the desorption of hydrogen and the increase of film density, hardness and refractive index. In this study, we investigated SR irradiation effects on the H-DLC with different hydrogen contents. The H-DLC thin films were deposited on an Si wafer with 200 nm thickness by an amplitude-modulated radio frequency plasma chemical vapor deposition method. The SR irradiation was carried out at NewSUBARU BL6. The SR has a continuous spectrum from IR to soft X-ray, which is lower than 1 keV. The hydrogen content dependence on SR dose was estimated using elastic recoil detection analysis (ERDA) and Rutherford backscattering (RBS) techniques. The hydrogen content was kept constant in the low-hydrogenated DLC film, while that in the high-hydrogenated DLC film decreased exponentially with soft X-ray dose.
Kanda, Kazuhiro*; Yokota, Kumiko*; Tagawa, Masahito*; Tode, Mayumi; Teraoka, Yuden; Matsui, Shinji*
Japanese Journal of Applied Physics, 50(5), p.055801_1 - 055801_3, 2011/05
Times Cited Count:13 Percentile:47.65(Physics, Applied)Tode, Mayumi; Harries, J.; Teraoka, Yuden; Yoshigoe, Akitaka
Denki Gakkai Rombunshi, C, 130(10), p.1819 - 1820, 2010/10
In order to study the thermal degradation process of the hydrogen storage materials surface layer and the thermal desorption of hydrogen property, we have used high-resolution synchrotron radiation X-ray photoelectron spectroscopy. The experiments were performed at the JAEA soft X-ray beamline BL23SU at SPring-8, using the "SUREAC2000" surface reaction analysis apparatus. Spectra were recorded for two samples (VCr
Ti
) covered with native oxide layers, one of which was implanted with deuterium ions. For the un-implanted sample, the oxide layer changes dramatically between 373 K and 473 K, for the deuterium-implanted sample, the change occurs between 473 K and 573 K. The implantation of deuterium leads to a stabilization (of approximately 100 K) of the surface oxide layer.
Hashinokuchi, Michihiro*; Sumimoto, Yuichi*; Tode, Mayumi; Harries, J.; Okada, Michio*; Teraoka, Yuden; Kasai, Toshio*
Denki Gakkai Rombunshi, C, 130(10), p.1723 - 1729, 2010/10
The oxidation processes on a TiAl surface induced by a hyperthermal O molecular beam (HOMB) with a translational energy of 2.2 eV was studied by X-ray photoemission spectroscopy in conjunction with synchrotron radiation. At a surface temperature of 300 K, the simultaneous growth of Al and Ti oxides accompanied with the segregation of Al
O
near the surface was observed. The efficiency of oxidation for the HOMB incidence was smaller than that for O
backfilling (25 meV). Furthermore, the chemical compositions of oxide species (Al
O
, Ti
O
, TiO
) on the TiAl surface were independent of the translational energy of incident O
molecule. The present results suggest that the oxidation on TiAl surface proceeds via precursor molecular states.
Kanda, Kazuhiro*; Tagawa, Masahito*; Yokota, Kumiko*; Tode, Mayumi; Teraoka, Yuden; Matsui, Shinji*
no journal, ,
In this study, hydrogen desorption processes from highly-hydrogenated DLC films have been investigated by thermal desorption mass stectrometry (TDS) and elastic recoil detection analysis (ERDA). The soft X-ray irradiation was performed at BL-6 in NewSUBARU. The white light is containing infra red to 1000 eV X-ray. The TDS measurements were performed using the thermal desorption measurement system at BL23SU in SPring-8. Although a large peak was observed at around 470 K in the non-X-ray-irradiated DLC film, the peak almost disappeared after irradiation of 300 mAhr synchrotron radiation. ERDA measurements resulted in no change of hydrogen content for lowly-hydrogenated DLC film instead of large decrease of hydrogen for highly-hydrogenated DLC film depending on soft X-ray dose. Hydrogen molecules, which are seen in a TDS spectrum as a low temperature peak, desorb by soft X-ray irradiation so that density and reflective index are changed.
Hashinokuchi, Michihiro*; Sumimoto, Yuichi; Tode, Mayumi; Okada, Michio*; Harries, J.; Yoshigoe, Akitaka; Teraoka, Yuden; Kasai, Toshio*
no journal, ,
We have studied chemical reactions of TiAl surface with oxygen molecules by using synchrotron radiation photoelectron spectroscopy to clarify the generation process of Al oxides. The experiment was conducted with the surface chemistry experimental station (SUREAC2000) at the soft X-ray beamline (BL23SU) of Japan Atomic Energy Agency in the SPring-8 facilities. The surface (50at.%) was cleaned by Ar ion sputtering and annealing. Comparing the Al-2p and Ti-2p XPS spectra of the clean surface with those of the surface exposed to the oxygen of 350L at 673K, it has been found that the peak position and profile were changed. It shows that both Ti and Al atoms were oxidized. Moreover, the Ti oxides was decreased by heating up to 1123K.
Tode, Mayumi; Harries, J.; Teraoka, Yuden; Yoshigoe, Akitaka
no journal, ,
In order to study the relationships between the thermal desorption of hydrogen and the surface properties we have used high-resolution synchrotron radiation X-ray photoelectron spectroscopy to study the thermal degeneration processes of the surface layers. The experiments were performed at the JAEA soft X-ray beamline BL23SU at SPring-8, using the "SUREAC2000" surface reaction analysis apparatus. Spectra were recorded for two samples (VCr
Ti
) covered with native oxide layers, one of which was implanted with deuterium ions. For the un-implanted sample, the oxide layer changes dramatically between 373 K and 473 K, for the deuterium-implanted sample, the change occurs between 473 K and 573 K. The implantation of deuterium leads to a stabilization (of approximately 100 K) of the surface oxide layer.
Harries, J.; Tode, Mayumi; Sumimoto, Yuichi; Inoue, Keisuke; Yoshigoe, Akitaka; Teraoka, Yuden
no journal, ,
Photoelectron spectroscopy is predominantly a surface-sensitive technique, but by recording spectra at a range of angles information on the depth-dependent distribution of elements in specific chemical states can also be obtained. Compared to other techniques such as Rutherford back-scattering, the technique has the advantage of chemical-state specificity, but the drawback that it requires very careful data analysis to produce reliable and quantitative results. Here we report progress in obtaining chemical-state depth profiles from photoelectron spectra recorded using the SUREAC2000 apparatus at SPring-8's BL23SU. Results will be presented for ARXPS data recorded for N and O layers on Al(111), and also a VCrTi sample, both in its as-received state and following deuterium ion dosing.
Harries, J.; Tode, Mayumi; Sumimoto, Yuichi; Inoue, Keisuke; Yoshigoe, Akitaka; Teraoka, Yuden
no journal, ,
Using the high energy resolution surface chemistry apparatus at SPring-8's BL23SU it is possible to record angular and chemical-state resolved X-ray photoelectron spectra. Chemical-state specific depth profile information can be obtained from these spectra using the maximum entropy method. Here we describe progress made in the combination of these two techniques, with the specific example of the depth-profiling of various nitridation states present in a Al(111) sample nitrided using a supersonic molecular beam.
Harries, J.; Tode, Mayumi; Inoue, Keisuke; Sumimoto, Yuichi; Yoshigoe, Akitaka; Teraoka, Yuden
no journal, ,
There are many available methods for determining the elemental distributions within a sample in the depth direction, but angle-resolved X-ray photoelectron spectroscopy offers the advantage of chemica-state specificity. At the surface chemistry station at BL23SU, SPring-8, we have recorded depth-profiles for thin films generated using supersonic molecular beams and ion beams. To extract the depth-direction information from the angular resolved spectra we use the maximum entropy method. We explain the techniques, and present the specific example of the natural oxide of VCrTi, a hydrogen storage material. Also, we investigate the thermal stability of the oxide by generating depth profiles during annealing of the sample.
Tagawa, Masahito*; Yokota, Kumiko*; Furuyama, Yuichi*; Tode, Mayumi; Yoshigoe, Akitaka; Teraoka, Yuden
no journal, ,
In order to make clear an effect of surface oxide layers for hydrogen desorption processes of hydrogen storage materials, ultra-thin metal oxide layers were formed on diamond-like-carbon (DLC) surfaces containing hydrogen and metals by irradiation of atomic oxygen beams. The thickness of SiO layer formed by the atomic oxygen beam irradiation was estimated to be about 4.5-6.5 nm on the basis of Si
/Si
photoemission peak area ratio. This value is larger than the diffusion depth of oxygen atoms in an Si crystal at a room temperature. Thermal desorption gas analyses revealed that a hydrogen desorption temperature did not change by the atomic oxygen beam irradiation. However, a hydrogen desorption temperature decreased in the atomic oxygen beam irradiation to a DLC containing Ti. The variation of hydrogen desorption temperature depends on a kind of metal oxide layer.
Tode, Mayumi; Harries, J.; Teraoka, Yuden; Yoshigoe, Akitaka
no journal, ,
In order to study the relationships between the thermal desorption of hydrogen and the surface layer, we have used high-resolution synchrotron radiation X-ray photoelectron spectroscopy to study the thermal degeneration processes of the surface layers. The experiments were performed at the JAEA soft X-ray beamline BL23SU at SPring-8, using the "SUREAC2000" surface reaction analysis apparatus. XPS spectra were recorded for room temperature TiFe and V25Cr40Ti35 following flash heating to 373-1073 K. In the un-deuterium implanted TiFe, the photoelectron spectra have changed when heating it at the temperature of 573 K. In the deuterium implanted TiFe, the photoelectron spectra have changed when heating it at the temperature of 473 K. When the deuterium ion was injected, the thermal degeneration temperature of a natural oxide layer was observed to shift to the low temperature side by 150 C.
Tode, Mayumi; Harries, J.; Teraoka, Yuden; Yoshigoe, Akitaka
no journal, ,
In order to study the relationships between the thermal desorption of hydrogen and the surface properties, we have used high-resolution synchrotron radiation X-ray photoelectron spectroscopy to study the thermal degeneration processes of the surface layers. An artificial oxide layer was formed on the surface of V, and thermal desorption spectrometry of deuterium was measured. All experiments have been conducted at the surface chemistry experimental station (SUREAC2000) at BL23SU, SPring-8. V-2p and O-1s peaks were observed by SR-XPS. An artificial oxide layer on V is degeneration between 300K and 373K. After the resolution of the oxide layer, deuterium is desorbed.
Tode, Mayumi; Harries, J.; Teraoka, Yuden; Yoshigoe, Akitaka
no journal, ,
In order to study the relationships between the thermal desorption of hydrogen and the surface properties, we have used high-resolution synchrotron radiation X-ray photoelectron spectroscopy to study the thermal degeneration processes of the surface layers. The experiments were performed at the JAEA soft X-ray beamline BL23SU at SPring-8, using the "SUREAC2000" surface reaction analysis apparatus. XPS spectra were recorded for room temperature TiFe and VCr
Ti
following flash heating to 373-1073 K. Spectra were recorded for two samples covered with native oxide layers, one of which was implanted with deuterium ions. In the deuterium-implanted TiFe, the temperature to which it begins to resolve the oxide component has lowered at about 200-250
C. On the other hand, in VCrTi, the thermal stability of a surface natural oxide layer has increased by the deuterium-implanted.
Tode, Mayumi; Harries, J.; Teraoka, Yuden; Yoshigoe, Akitaka
no journal, ,
Research into the correlation between surface degeneration layer control and hydrogen desorption temperature characteristic of the hydrogen storage materials. The degeneration process was observed by the high-resolution synchrotron radiation X-ray photoelectron spectroscopy. The desorption degree of hydrogen was observed by thermal desorption spectrometry. The experiments were performed at the JAEA soft X-ray beamline BL23SU at SPring-8, using the "SUREAC2000" surface reaction analysis apparatus. Spectra were recorded for two samples(VCr
Ti
) covered with native oxide layers, one of which was implanted with deuterium ions. For the un-implanted sample, the oxide layer changes dramatically between 373 K and 473 K, for the deuterium-implanted sample, the change occurs between 473 K and 573 K. The implantation of deuterium leads to a stabilization (of approximately 100 K) of the surface oxide layer.
Hashinokuchi, Michihiro*; Sumimoto, Yuichi*; Tode, Mayumi; Okada, Michio*; Harries, J.; Teraoka, Yuden; Kasai, Toshio*
no journal, ,
The oxidation processes on a TiAl surface induced by a hyperthermal O molecular beam (HOMB) with a translational energy of 2.2 eV was studied by X-ray photoemission spectroscopy in conjunction with synchrotron radiation. At a surface temperature of 300 K, the simultaneous growth of Al and Ti oxides accompanied with the segregation of Al
O
near the surface was observed. The efficiency of oxidation for the HOMB incidence was smaller than that for O
backfilling (25 meV). Furthermore, the chemical compositions of oxide species (Al
O
, Ti
O
, TiO
) on the TiAl surface were independent on the translational energy of incident O
molecules. The present results suggest that the oxidation on a TiAl surface proceed via molecular adsorption as a precursor state.