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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：18.81(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
Cr
Ti
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
Times Cited Count：13 Percentile：47.31(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.
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 AlO
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 (AlO, TiO, 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.
CrTi using synchrotron radiation photoelectron spectroscopyTode, 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 (VCrTi) 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; 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.
Tode, Mayumi; Harries, J.; Teraoka, Yuden; Sumimoto, Yuichi; Inoue, Keisuke; Yoshigoe, Akitaka
no journal, ,
Thermal stability of native oxide layer on the hydrogen storage materials is related to the hydrogen absorption and desorption. In this study, thermal degradation process of native oxide layer on VCrTi was observed by high resolution soft X-ray synchrotron radiation photoemission spectroscopy. All experiments have been conducted at the surface chemistry experimental station (SUREAC2000) at BL23SU, SPring-8. Before thermal annealing, photoemission spectrum of oxide was observed. After thermal annealing, the oxide peak was decreased, and the metal peak was increased. When the deuterium ion was implanted into the surface, the degeneration temperature of a natural oxide layer was observed to rise about 100 degrees.
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.
Hashinokuchi, Michihiro*; Sumimoto, Yuichi; Tode, Mayumi; Harries, J.; Teraoka, Yuden; Okada, Michio*; Kasai, Toshio*
no journal, ,
The oxidation processes on TiAl are complex and the composition of the oxide layer depends on various oxidation parameters like sample temperature and oxygen pressure. Therefore, the aim of this work was to examine the initial stages of oxidation of TiAl under different oxidation temperatures and the different kinetic energy of incident oxygen by using X-ray photoemission spectroscopy in conjunction with synchrotron radiation. All experiments were performed with a surface reaction analysis apparatus (SUREAC2000) constructed in BL23SU at SPring-8. The TiAl sample was cleaned by repeatedly argon ion sputtering and annealing. The Oxygen molecules were dosed on the TiAl by hyperthermal oxygen molecular beams or by backfilling oxygen gas.
Kanda, Kazuhiro*; Teraoka, Yuden; Tode, Mayumi; Matsui, Shinji*
no journal, ,
In order to investigate soft X-ray irradiation effects for a diamond-like carbon (DLC) film, thermal desorption spectra (TDS) were observed for a hydrogenated DLC film and a soft X-ray irradiated (300 mAh) hydrogenated DLC film. The temperature elevation rate was 87.5 K/min and the temperature range was from 373 K to 1073 K. In the case of TDS for hydrogen molecules, a large peak was observed around 470 K in the hydrogenated DLC film. The peak, however, was not observed in the non-irradiated hydrogenated DLC film. The elastic recoil analysis showed a large decrease of hydrogen in the X-ray irradiated (300 mAh) sample. We concluded on the basis of these observations that hydrogen molecules desorb by soft X-ray irradiation of 300 mAh.
Tagawa, Masahito*; Yokota, Kumiko*; Furuyama, Yuichi*; Kanda, Kazuhiro*; Tode, Mayumi; Yoshigoe, Akitaka; Teraoka, Yuden
no journal, ,
Effects of vacuum ultraviolet and surface oxide layer on the hydrogen desorption from hydrogenated diamond-like carbon (HDLC) films were investigated. We have used commercially available HDLC as a specimen, and synchrotron radiation at BL-6 in NewSUBARU or D lamp as an external source of photon energy. SiO and TiO surface oxide films with a few nanometer thickness were formed by irradiation of hyperthermal atomic oxygen beams with a translational energy of approximately 5 eV onto metal-doped HDLCs in order to investigate the effect of oxide film on the hydrogen desorption. It was confirmed that the effect of SiO and TiO gave different influence on desorption temperature of hydrogen.
Tode, Mayumi; Harries, J.; Teraoka, Yuden; Sumimoto, Yuichi; Inoue, Keisuke; Yoshigoe, Akitaka
no journal, ,
Tode, Mayumi; Harries, J.; Teraoka, Yuden; Yoshigoe, Akitaka
no journal, ,
Thermal stability of native oxide layer on the hydrogen storage materials is related to the hydrogen absorption and desorption. In this study, thermal degradation process of native oxide layer on TiFe was observed by high resolution soft X-ray synchrotron radiation photoemission spectroscopy. All experiments have been conducted at the surface chemistry experimental station (SUREAC2000) at BL23SU, SPring-8. After thermal annealing, the peak that shows the oxidation weakens, and the peak that shows the metal strengthens. The thermal stability of a natural oxide layer was observed to stabilize by about 200 degrees by deuterium ion implanted.
Kanda, Kazuhiro*; Yokota, Kumiko*; Tagawa, Masahito*; Tode, Mayumi; Teraoka, Yuden; Matsui, Shinji*
no journal, ,
In the present study, we investigated the desorption of hydrogen from highly-hydrogenated diamond-like-carbon (DLC) films by irradiation of synchrotron radiation (SR) soft X-rays in vacuum. The irradiation of SR was carried out at BL-6 of NewSUBARU. The SR energy is ranging from infra red to soft X-ray, which was lower than 1 keV. The hydrogen content in the DLC films has been determined by Rutherford backscattering (RBS) and elastic recoil detection analysis (ERDA) techniques. Although the hydrogen content in the low-hydrogenated DLC film was independent on the soft X-ray dose, that for the high-hydrogenated DLC film decreased exponentially with the soft X-ray dose. This implies that the desorption of hydrogen takes place from the high-hydrogenated DLC films by the soft X-ray irradiation.
CrTi) using high-resolution soft X-ray synchrotron radiation photoelectron spectroscopyTode, Mayumi; Harries, J.; Teraoka, Yuden; Sumimoto, Yuichi; Inoue, Keisuke; Yoshigoe, Akitaka
no journal, ,
Thermal stability of native oxide layer on the hydrogen storage materials is related to the hydrogen absorption and desorption. Thermal instability of native oxide layer on VCrTi and deuterated VCrTi was observed by high resolution soft X-ray synchrotron radiation photoemission spectroscopy. All experiments have been conducted at the surface chemistry experimental station (SUREAC2000) at BL23SU, SPring-8. After thermal annealing, the peak that shows the oxidation weakens, and the peak that shows the metal strengthens. The thermal stability of a natural oxide layer was observed to stabilize by about 100 degrees by deuterium ion implanted.
Tode, Mayumi; Harries, J.; Teraoka, Yuden; Sumimoto, Yuichi; Inoue, Keisuke; Yoshigoe, Akitaka
no journal, ,
Study of thermal desorption characteristics of native oxide layer on the surface of the hydrogen storage materials is very important. Thermal instability of native oxide layer on VCrTi and deuterated VCrTi was observed by high resolution soft X-ray synchrotron radiation photoemission spectroscopy. All experiments have been conducted at the surface chemistry experimental station (SUREAC2000) at BL23SU, SPring-8. Before thermal annealing, the satellite peak from the native oxide layer and the V-2p peak from the bulk were observed. The O-1s peak consisted of at least two components. After thermal annealing, the O-1s peak decreases and the V-2p peak increases. Deuterium implantation affected the thermal stability of the native oxide.
CrTi using high-resolution soft X-ray synchrotron radiation photoelectron spectroscopyTode, 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 (VCrTi) 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.
