Journal of the Vacuum Society of Japan
Online ISSN : 1882-4749
Print ISSN : 1882-2398
ISSN-L : 1882-2398
55 巻 , 8 号
  • Shota TAKAMARU, Tomoaki HINO, Yuji YAMAUCHI
    2012 年 55 巻 8 号 p. 395-398
    発行日: 2012年
    公開日: 2012/09/01
    ジャーナル フリー
      As the anode material, natural graphite, polymer-coated natural graphite, carbon-coated natural graphite and artificial graphite were employed. In order to examine the effect of solid electrolyte interface (SEI), these samples were exposed to the cycles of charge/discharge. The gas desorption behavior of these samples was investigated by using a technique of thermal desorption spectroscopy. The amount of desorbed gasses significantly increased after a charge/discharge cycle. The increase of the desorbed amount was associated with gas desorption from SEI formed in the first cycle. The amount of desorbed gasses increases with an irreversible capacity in the first charge/discharge cycle. The irreversible capacity of surface-coated graphite and artificial graphite was lower than that of natural graphite. The surface coating resulted in the decrease of the amount of desorbed gasses and irreversible capacity. The atomic composition was measured by auger electron spectroscopy. Carbon, Oxygen, fluorine and phosphorus were observed after a charge/discharge cycle.
  • 吉田 大一郎, 木下 健太郎, 三浦 寛基, 高橋 智一, 岸田 悟
    2012 年 55 巻 8 号 p. 399-402
    発行日: 2012年
    公開日: 2012/09/01
    ジャーナル フリー
      Estimating intrinsic electric properties of freestanding BaTiO3 (BTO)/Pt films had been prevented due to leakage current caused by insufficient insulation of the BTO film. This poor insulation is attributed to difficulty in preparation of Pt foils with the flat surface. The present study showed that the flatness of the surface of Pt foils is improved by thinning the carbon (C) buffer layer placed between the Pt layer and Si substrate in Pt/C/Si structure, where the C layer is ablated by annealing in the ambient. By thinning the thickness of the C layer from 166 to 66 nm, the leakage current at 86 kV/cm was drastically improved by more than four orders in magnitude from 1×10−3 A/cm2 to 2×10−8 A/cm2.
  • Sadanori ARAE, Takahiko YAMAZAKI, Kohtaro YANASE, Keita OCHI, Asuka IS ...
    2012 年 55 巻 8 号 p. 403-404
    発行日: 2012年
    公開日: 2012/09/01
    ジャーナル フリー
      We constructed a simple atomic hydrogen source mounted on a conflat flange with an outer diameter of 70 mm (CF70). The source consists of a tungsten filament, a hydrogen gas inlet, and two feedthroughs. The filament is surrounded by a CF70 nipple made of 0.2% beryllium copper alloy and oxygen-free cupper gaskets to reduce the outgassing rate. Using this hydrogen source, we hydrogenated a clean Si(111)-7×7 surface at room temperature. Low energy electron diffraction patterns and Auger electron spectra were measured before and after the hydrogenation.