Synchrotron radiation, which has characteristics of high energy, high brilliance, high directionality, and high polarization, is a useful light source for the evaluation of thin film. International standardization project of diamond-like carbon (DLC) film is proceeding on the basis of the measurement of the near edge X-ray absorption fine structure (NEXAFS) spectroscopy using synchrotron radiation. NEXAFS has been utilized as a precise method of sp² content for DLC films. The sp² content can be extracted from the NEXAFS spectrum with a high sensitivity and a high quantitativity, because the isolated peak corresponding to carbon 1s→π* resonance transition can be observed.

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  Lithium ion batteries will be important to the future generations for use as clean energy-storage devices. However, the surface chemical reaction mechanism of the electrode has not been revealed to date. In case of Li-ion batteries, CoO and/or Co₃O₄ are considered as the degradation materials in LiCoO₂ cathode. In order to estimate the chemical state of cathode material, the comparison of secondary ion spectrum of LiCoO₂, CoO and Co₃O₄ were made. In this study, secondary ion analyses of cobalt compounds were performed using a laboratory-made TOF-SIMS apparatus.

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  A band diagram measurement system was developed that consists of a spectrophotometer system and a photoemission yield measurement system, and is applicable to organic semiconductor materials such as organic light emitting devices (OLEDs). The system is designed to simultaneously measure optical (reflectance, luminescence, thickness and bandgap) and electronic properties (ionization potential and electron density of states) at the same position. A band diagram shows the absolute values of the highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) energy levels from the vacuum level. The HOMO level is obtained from the ionization potential and the LUMO level is estimated from the HOMO and the optical bandgap. Band diagram measurements for typical organic semiconductor materials are demonstrated, and obtained band diagrams are in agreement with reported values.

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  Effects of hydrogen plasma exposure in polymer dry etching processes have been investigated with a low-energy mass-selected ion beam system. In the present study, we use a spin-coated polymethylmethacrylate (PMMA) film on a quartz crystal microbalance as a model polymer. The surface modification of the PMMA film by the hydrogen plasma exposure in an inverter plasma system was investigated by X-ray photoelectron spectroscopy (XPS) and spectroscopic ellipsometry. XPS results show that oxygen atoms were preferentially sputtered from the PMMA film by the hydrogen plasma exposure. Spectroscopic ellipsometry results show that depth of the modified layer of the hydrogen plasma exposed PMMA film was about 40 nm. Etching yields of the pristine PMMA film and the hydrogen plasma exposed PMMA film by 470 eV Ar⁺ ion beam injections were measured. It is found that the etching yield of the hydrogen plasma exposed PMMA film was about half of that of the pristine PMMA film.

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  Thermal degradation property of fluorocarbon thin film prepared by an r.f. sputtering and poly (tetrafluoroethylene) (PTFE) thin film prepared by a spin coating technique was analyzed with a micro sampling mass spectroscopy and an effect of atomic oxygen exposure on the property of these thin films was evaluated. Main thermal degradation products of the PTFE thin film are C₂F₄ and C₂F₃, however those of the fluorocarbon thin film are CO₂, CF₃ and C₄F₇. Fragments which represent CF₃, C₂F₅, C₃F₇, C₃F₅, C₄F₇ were observed in the spectrum of sputtered fluorocarbon thin films, while they were hardly obaserved in that of PTFE thin film. It is considered that these fragments would relate the thermal stability of the fluorocarbon thin film.

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  Field effect transistor (FET) was fabricated using MBE grown Si:Ce magnetic semiconductor films. To suppress the inter-diffusion between ferroelectric and Si:Ce layer, organic ferroelectric film, P(VDF-TeFE) which can be grown below 200℃ was used. By improving the surface roughness by optimizing the spin coat process condition, P(VDF-TeFE) films with ferroelectric behavior and high insulation property were successfully fabricated on Si:Ce thin films. Eventually, ferroelectric type C-V hysteresis was observed. High frequency C-V measurement shows a decrease of capacitance suggesting a formation of depletion layer in a negative bias region. Low frequency C-V measurement reveals an increase of capacitance suggesting a formation of inversion layer.

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  We investigated the magnetic property of Co/Ni multi-layers on W(110), using first principles calculation based on density functional theory. We found that one atomic monolayer of Ni (Ni 1ML) and two atomic monolayers of Ni (Ni 2ML) on W(110) exhibited no magnetic moment. These results occur because the minority spin states of Ni atoms are occupied by the electrons transferred from W atoms. These results also agree with the experimental results where the 1ML and 2ML of Ni layers exhibited no magnetic anisotropy. We calculated the magnetic anisotropy energy in each of the three directions, viz., the two surface in-plane directions and one surface out-of-plane direction, in Ni 1ML, Ni 2ML and Co 1ML/Ni 2ML on W(110). We found that the Co surface atoms of Co 1ML/Ni 2ML exhibit surface in-plane magnetic anisotropy. We also estimated the effect of magnetic dipole-dipole interaction on the magnetic anisotropy energy in a Co 1ML/Ni 2ML multi-layer on W(110). We found that the effect is not dominant.

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  Monte-Carlo method is useful for the transmission probability calculation of a complicated-shaped tube under molecular flow conditions. However the shape data should be fed into the computer for each simulation. In the present study, transmission probability was calculated by KPCalc, which is the Monte-Carlo simulation software. KPCalc can calculate the transmission probability from the 3D-CAD data without preparing the source code of the shape data. Therefore, KPCalc is easily applied even for the complicated shape which the conventional Monte-Carlo method was hardly applied because of much labor. Calculation was carried out for cylindrical tubes, conical tubes, and bellows-shaped tubes. Results are in good agreement with previous results within the data scattering. As an example, transmission probabilities of formed bellows tubes with a complicated shape were calculated.

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  Monte Carlo simulations of a molecular flow regime demonstrate the generation of large-scale gas-sheet targets in a vacuum by two typical gas inlet systems. One inlet system consists of a set of identical narrow rectangular slits; they are placed in rotational symmetry around an axis in a manner such that all the slits have the same plane that is orthogonal to their short sides. This plane divides all the slits into halves. The other inlet system consists of a thin concentric circular slit with a large aperture. In both these systems, gas is introduced from the outside toward the center, leading to the appearance of a large-scale gas sheet around the center. In the case of the circular slit, with inner and outer diameters of 200 and 400, respectively, and a gap of 0.1, the generated gas sheet had a diameter of 130 and thickness of less than 0.4 (half width), where all the valuables are expressed in ratio. The uniformity of the gas density, which is the ratio of the minimum to the maximum peak value of gas density, was more than 85%.

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