The Experts below are selected from a list of 237 Experts worldwide ranked by ideXlab platform

Akira Heya - One of the best experts on this subject based on the ideXlab platform.

  • Reduction and Etching of Si-Rich SiOx Film by Atomic Hydrogen Annealing
    2019 26th International Workshop on Active-Matrix Flatpanel Displays and Devices (AM-FPD), 2019
    Co-Authors: Akira Heya
    Abstract:

    To clarify the influence of Atomic Hydrogen on various materials is required for realization of a sustainable society using Hydrogen energy. The influence of Atomic Hydrogen was investigated from the reaction of Si-rich SiOx film on a Si wafer using Atomic Hydrogen annealing (AHA). In AHA, the high-density Atomic Hydrogen is generated on a heated tungsten surface by catalytic cracking reaction. The Si-rich SiOx film was reduced by AHA. The Si-rich SiOx film was etched with an etching rate of 1.0 nm/min. It is considered that the chemical reactions of reduction and etching are originated from disordered bond network due to Si rich region. The Si-rich SiOx film is expected to be used as an Atomic Hydrogen sensor.

  • Reduction and Etching of Si-Rich SiO x Film by Atomic Hydrogen Annealing
    2019 26th International Workshop on Active-Matrix Flatpanel Displays and Devices (AM-FPD), 2019
    Co-Authors: Akira Heya
    Abstract:

    To clarify the influence of Atomic Hydrogen on various materials is required for realization of a sustainable society using Hydrogen energy. The influence of Atomic Hydrogen was investigated from the reaction of Si-rich SiO x film on a Si wafer using Atomic Hydrogen annealing (AHA). In AHA, the high-density Atomic Hydrogen is generated on a heated tungsten surface by catalytic cracking reaction. The Si-rich SiO x film was reduced by AHA. The Si-rich SiO x film was etched with an etching rate of 1.0 nm/min. It is considered that the chemical reactions of reduction and etching are originated from disordered bond network due to Si rich region. The Si-rich SiO x film is expected to be used as an Atomic Hydrogen sensor.

  • Reduction of graphene oxide by Atomic Hydrogen annealing
    2016 23rd International Workshop on Active-Matrix Flatpanel Displays and Devices (AM-FPD), 2016
    Co-Authors: Akira Heya, Naoto Matsuo
    Abstract:

    Effect of Atomic Hydrogen annealing (AHA) on graphene oxide (GO) was investigated. In AHA, the high-density Atomic Hydrogen is generated on heated tungsten (W) surface by catalytic cracking reaction. From X-ray photoelectron spectra, GO films were reduced by AHA. The sheet resistance of the GO film was decreased by 5 orders of magnitude at W mesh temperature of 1780 °C, sample temperature of 220 °C and treatment time of 1800 s. The reduction of GO films relates chemical reaction due to Atomic Hydrogen because the GO films was not reduced by He treatment. The C-O-C bonds in GO films were preferentially reduced by AHA.

  • Surface Modification of Plastic Substrates Using Atomic Hydrogen
    Journal of The Vacuum Society of Japan, 2008
    Co-Authors: Akira Heya, Naoto Matsuo
    Abstract:

    The surface properties of a plastic substrate were changed by a novel surface treatment called Atomic Hydrogen annealing (AHA). In this method, a plastic substrate was exposed to Atomic Hydrogen generated by cracking of Hydrogen molecules on heated tungsten wire. Surface roughness was increased and halogen elements (F and Cl) were selectively etched by AHA. In addition, plastic surface was reduced by AHA. The surface can be modified by the recombination reaction of Atomic Hydrogen, the reduction reaction and selective etching of halogen atom. It is concluded that this method is a promising technique for improvement of adhesion between inorganic films and plastic substrates at low temperatures.

J. T. Yates - One of the best experts on this subject based on the ideXlab platform.

  • Reflector Atomic Hydrogen source: A method for producing pure Atomic Hydrogen in ultrahigh vacuum
    Journal of Vacuum Science and Technology, 1993
    Co-Authors: K. H. Bornscheuer, S. R. Lucas, W. D. Partlow, Wolfgang J. Choyke, J. T. Yates
    Abstract:

    A tungsten filament Atomic Hydrogen source placed in an effusive H2 molecular beam has been combined with a cryogenically cooled Pyrex reflector. This arrangement permits efficient production and transfer of Atomic Hydrogen to a sample surface by a non‐line‐of‐sight route. The arrangement eliminates most radiation heating of the sample. With the beam source, high local H2 gas densities and Atomic Hydrogen production rates in the filament region may be achieved without producing excessive gas loads in an ultrahigh vacuum system. A silicon(100) crystal sample was used in this study. The indirect source protects the sample from possible metal contamination evolving from the hot tungsten filament, and efficiently delivers only Atomic and molecular Hydrogen species to the sample. The efficiency of this arrangement has been quantitatively compared to a line‐of‐sight filament source of Atomic Hydrogen.

  • Inhibition of Atomic Hydrogen Etching of Si(111)
    1991
    Co-Authors: P. J. Chen, M. L. Colaianni, J. T. Yates
    Abstract:

    Abstract : Subsurface boron doping reconstructs the Si(111) surface and alters the electronic character of the surface Si atoms. The interaction of Atomic Hydrogen with the boron-modified Si(111) - (V3xV3) - R30 surface was studied using temperature programmed desorption (TPD), high resolution electron energy loss spectroscopy (HREELS) and low energy electron diffraction (LEED). In comparison to the Si(111) - (7x7) surface, we observe a significantly reduced Hydrogen saturation coverage, measured by TPD and HREELS, and the absence of silane production. The ordered (1/3 ML) subsurface boron atoms passivate the surface Si atoms and reduce their reactivity with Atomic Hydrogen. This leads to a surface condition causing suppression of silicon etching by Atomic Hydrogen, compared to the unmodified Si(111) - (7x7) surface.

Naoto Matsuo - One of the best experts on this subject based on the ideXlab platform.

  • Reduction of graphene oxide by Atomic Hydrogen annealing
    2016 23rd International Workshop on Active-Matrix Flatpanel Displays and Devices (AM-FPD), 2016
    Co-Authors: Akira Heya, Naoto Matsuo
    Abstract:

    Effect of Atomic Hydrogen annealing (AHA) on graphene oxide (GO) was investigated. In AHA, the high-density Atomic Hydrogen is generated on heated tungsten (W) surface by catalytic cracking reaction. From X-ray photoelectron spectra, GO films were reduced by AHA. The sheet resistance of the GO film was decreased by 5 orders of magnitude at W mesh temperature of 1780 °C, sample temperature of 220 °C and treatment time of 1800 s. The reduction of GO films relates chemical reaction due to Atomic Hydrogen because the GO films was not reduced by He treatment. The C-O-C bonds in GO films were preferentially reduced by AHA.

  • Surface Modification of Plastic Substrates Using Atomic Hydrogen
    Journal of The Vacuum Society of Japan, 2008
    Co-Authors: Akira Heya, Naoto Matsuo
    Abstract:

    The surface properties of a plastic substrate were changed by a novel surface treatment called Atomic Hydrogen annealing (AHA). In this method, a plastic substrate was exposed to Atomic Hydrogen generated by cracking of Hydrogen molecules on heated tungsten wire. Surface roughness was increased and halogen elements (F and Cl) were selectively etched by AHA. In addition, plastic surface was reduced by AHA. The surface can be modified by the recombination reaction of Atomic Hydrogen, the reduction reaction and selective etching of halogen atom. It is concluded that this method is a promising technique for improvement of adhesion between inorganic films and plastic substrates at low temperatures.

Junji Nakamura - One of the best experts on this subject based on the ideXlab platform.

  • Atomic Hydrogen storage in carbon nanotubes promoted by metal catalysts
    Journal of Physical Chemistry B, 2004
    Co-Authors: Toshiki Komatsu, N Yagai, K Arai, T Yamazaki, Kiyoto Matsuishi, Taketoshi Matsumoto, Junji Nakamura
    Abstract:

    Atomic Hydrogen storage by carbon nanotubes (CNTs) at atmospheric pressure is studied using Pd and La catalysts for dissociation of H2 into Atomic Hydrogen and formation of defects on CNT surfaces, respectively. The defect sites on CNTs as adsorption sites of Atomic Hydrogen are prepared by oxidation pretreatment using a La catalyst. Pd catalysts are then deposited on CNT surfaces for dissociation of H2 into Atomic Hydrogen, which then spills over to the defect sites. In the best case, 1.0 wt % Hydrogen is stored in the defective CNT with Pd particles at 1 atm and 573 K. The Hydrogen desorption in temperature programmed desorption (TPD) experiments started at 700−900 K, which agreed with the annealing temperatures of CNTs prior to Hydrogen storage. Also, the amount of Hydrogen stored in CNTs decreased with increasing annealing temperature. These results are ascribed to the crystallization of the defective structure of CNT into graphitic structure. The activation energies of 46.6, 87.3, and 129.8 kJ/mol de...

Síle Nic Chormaic - One of the best experts on this subject based on the ideXlab platform.

  • Positron impact ionization of Atomic Hydrogen
    Journal of Physics B, 1993
    Co-Authors: G O Jones, M. Charlton, J Slevin, G. Laricchia, Á Kövér, M R Poulsen, Síle Nic Chormaic
    Abstract:

    Ionization cross sections for positrons impacting on Atomic Hydrogen have been measured for kinetic energies in the range 15-700 eV. This has been done in a crossed-beam geometry where a magnetically guided positron beam intersects a Hydrogen gas jet emanating from a radio frequency discharge tube. Electron impact ionization cross sections were also measured with the same apparatus thus facilitating comparison with, and normalization to, published results. The positron-Atomic Hydrogen results are found to be significantly lower than those obtained by Spicher et al. (1990).