Distribution function of the hitting number per molecule which comes from a localized outgassing source, when molecule exits the long tube of lenghth L, were calculated by Monte Carlo simulation method. Results are compared with the Green's function for the one-dimensional diffusion equation of virtually extended finite region of L+4 λ/3 with Dirichlet boundary condition (values are zero at both boundaries), where λ is mean free path of the molecules. It is found, that Green's function represents that distribution function well and also is available to estimate average arriving time of molecules from a localized outgassing source at exit.

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  A transmission probability W of gas molecules passing through a vacuum component is usually calculated using the Monte Carlo method. In the calculation, it is generally assumed that gas molecules are introduced to a smooth surface and scatter with cosine low. Since the W is influenced by the shape and/or roughness of the surface in practice, the precise calculation of W requires the inclusion of surface geometry. The conventional Monte Carlo method, however, needs very long time to calculate the W for a cylinder with many corrugations, in other words, rough surface. In this paper, a new method to decrease the time for a calculation with rough surface is described. In the new method, the scattering angle distribution distorted by corrugations is analytically calculated. The distorted distribution is used to determine the scattering angle of the gas molecules at the surface. In the case of a cylinder with the ratio of length to the radius L/r of 5, the ratio of the W with V-shaped corrugations to that without corrugations is 0.77 at minimum. Results of the calculation were obtained by both the new method and the conventional method, and are identical within 0.5%. The time required by the new method was more than 100 times shorter than that by the conventional one.

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  We report results of our detailed studies on the initial oxidation process of NiTi with a 2 eV hyperthermal oxygen molecular beam (HOMB) and thermal O₂ in the backfilling. The oxidation processes are monitored by X-ray photoemission spectroscopy measurements in conjunction with synchrotron radiation. In the oxide formation process at higher O coverage, HOMB has the advantage in the dissociation process of O₂ molecule and can grow TiO₂ layers with the underlying TiO_x-rich and/or Ni-rich layers even at room temperature. Surface annealing enhances the diffusion atoms and as a result, the efficiency of Ti oxide formation. We succeeded in fabricating thick Ni-free TiO₂ layer, possibly blue colored rutile TiO₂, combining HOMB and surface annealing.

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  Development of the precision gas generator tagged by a very small amount of the released gas rate in weight change (g/sec) has been strongly desired for exactly calibrating vacuum instruments.
  The gas-liquid equilibrium type, permeation tube (P-tube) for the Japanese Industrial Standards (JIS) to prepare the released rate of a calibration gas in an atmospheric pressure has not been used in vacuum elsewhere. Therefore in this study, the performance of the P-tube in vacuum environment was evaluated. A weight change of the P-tube was measured with our original vacuum microbalance, and concentrations of the released gas components were concurrently measured with the Electron Ionization Quadrupole Mass Spectrometer (EI-QMS), both in the different P-tube temperatures. The resultant correlation between the vacuum microbalance and the EI-QMS was discussed.
  The weight change rate of the sample propane (C₃H₈) and butane (C₄H₁₀) gases encapsulated in the P-tube were nearly identical from 35°C to 45°Cand from 40°C to 50°C, respectively. The EI-QMS peak intensities of m/z=29 (propane) and m/z=43 (butane) indicated constant values, both in the above temperature ranges.
  These results can be positioned to the initial performance data for realizing the weight change rate tagged precision gas generator in vacuum by using the P-tube.

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  We have developed a technique for depositing a metal compound thin film at a high deposition rate and low temperature. It involves repeatedly alternating between forming a very thin metal film by DC magnetron sputtering and converting the film into a very thin film of a metal compound by irradiating it with a radio-frequency plasma of an activated gas. We succeeded in preparing a WO₃ reduction coloring thin film with electrochromic properties at a high deposition rate (equivalent to that of tungsten metal) and a low substrate temperature (100°C or less). We then evaluated the possibility of forming a WO₃ reduction thin film with electrochromic properties using this technique by the CV method, with a spectrophotometer. We confirmed the effectiveness of this method by measuring the amount of transferred charge and the optical density change (ΔOD).

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  Gold- and palladium-doped tungsten oxide thin films were prepared by RF reactive sputtering in a mixture of argon and oxygen at room temperature and optical properties and electrochromic characteristics of the films were investigated. XRD patterns indicated that the films were amorphous. SEM imaging indicated that the grain size of gold- and palladium- doped thin films was smaller than that of the non- doped tungsten oxide thin films. By gold and palladium doping, the current- voltage characteristics show a significant change, even in the a bsorption of the film wearing the color reaction consumption, resulted in major changes.

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  Bi doped Nb₂O₅ oxide thin films were prepared by multi target radio frequency reactive sputtering in a gas mixture of argon and oxygen at 500°C. The films were amorphous according to a crystalline evaluation by X-ray diffraction. It was inferred from the result of the surface observation in the scanning electron microscope image that the mixture films created a corpuscle. X-ray photoelectron spectroscopy revealed that a chemical bond has changed by making a mixture film. These properties of prepared films strongly depended on the amount of Bi, and the films display a blue light burnt umber, burnt umber or black coloration after Li⁺ and electron insertion.

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J. Vac. Soc. Jpn., Vol. 54, No. 1 (2011), pp.72-76
Fig. 5 を下記の図に訂正します．

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