[in Japanese]

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A portable ultrahigh-vacuum sample transfer vessel is an important apparatus for transport a sample with active surfaces such as catalyst and battery material and it is important to know the contamination of the sample during its transport. In this study, two types of aluminum thin films with different film thicknesses were prepared by vacuum deposition method, and transported from the thin film manufacturing apparatus to the analysis apparatus using a portable ultrahigh-vacuum sample transfer vessel. The aluminum thin films were analyzed by photoelectron spectroscopy for carbon contamination and oxidation during transportation.

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We developed a new NEG coating using oxygen-free Pd/Ti thin film deposition. The advantages are that the pumping speed does not decline after repeated vent-activation cycles, and that the activation temperature is about 150°C. To investigate the thermal stability, we measured a series of XPS of Pd(50 nm)/Ti(1 μm) thin film as a function of annealing temperature in the range 100-360 °C. Ti was found to segregate close to the surface at 280 °C, and oxidizes at above 300 °C. The results indicate that the maximum allowable temperature of oxygen-free Pd/Ti films is approximately 260 °C.

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[in Japanese]

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We developed a new NEG coating by oxygen-free Pd/Ti thin film deposition. The advantages are that the pumping speed do not decline after repeated vent-activation cycles and the activation temperature is about 150°C. We observed the morphologies using scanning electron microscopy, transmission electron microscopy, scanning transmission electron microscopy, and energy-dispersive X-ray spectroscopy. The Ti and Pd films had almost uniform thicknesses of about 1.3 μm and 50 nm, respectively, and the Pd film completely overcoated the Ti film. Both the Pd and Ti thin films were uniformly deposited in plane on the substrate and they had polycrystalline structures.

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[in Japanese]

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[in Japanese]

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The difference of the value of the relative sensitivity coefficient of the ionization gauge described in references is examined by the simulation that uses the calculating formula including the term of the space charge.

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[in Japanese]

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Dexter triplet electron transfer is a special characteristic expected to be an application to signal delivery field, and the observation of Dexter-type transfer is the long-term goal of this research. Ir(ppy)₃ had been reported Dexter-type transfer would happen and inter-system-crossing efficiency is high. In this study, triplet excitons are generated by applying voltage to film with tunneling current, and neat Ir(ppy)₃ films I-V characteristics had been carried out, and layer thickness of film had been adjusted. The triplet excitons number is positively correlated to electrons injection number, and for getting stable excitons number, the film thickness optimization is undergoing.

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[in Japanese]

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[in Japanese]

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[in Japanese]

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[in Japanese]

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Recently researches on the ferromagnetism of graphene sheets have been vigorously conducted. In this study, the structure and magnetic properties of thermally annealed multilayer graphene oxide (MLGO) sheets were investigated. MLGO sheets on which a sonication in ethanol and an annealed in hydrogen atmosphere showed a ferromagnetic behavior, and its magnetization was 0.004 - 0.012emu/g. The coercivity was also observed. The obvious ferromagnetic behavior was not confirmed in single layer graphene oxide sheets on which the same processes were carried. These results may imply the multilayered structure plays a key role of the ferromagnetism in graphene oxide sheets.

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A high-density convergent plasma sputtering device has been developed to improve target use efficiency of ferromagnetic metals. Thin films are deposited on an unheated glass substrate by argon plasmas, using an iron target. Alpha iron films are obtained with a deposition rate of 25 nm/min at target-substrate distance of 58 mm and at sputtering gas pressure of 0.2 Pa.

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An atmospheric pressure plasma jet (APPJ) of helium gas was irradiated to a hydrophobic porous scaffold (inner diameter is 100-200 um) that has very poor water permeability. APPJ irradiation on the scaffold markedly improved water permeability of the scaffold. This result suggests that the inner surface of the porous scaffold was turned into hydrophilic by the APPJ irradiation. Active species fed from APPJ cannot penetrate narrow channel in the porous scaffold because of quite high collision frequency at atmospheric pressure. Thus, the improvement of water permeability may be explained in terms of propagation of plasma bullets through the porous scaffold.

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[in Japanese]

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[in Japanese]

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To elucidate tribological phenomena in nano-confined condition is crucial important subject in nanofabrication processes, such as nanoimprint. In nanoimprint, some tribological problems happen during pressing, releasing and alignment process. We previously investigated the behaviors of polymer materials (poly(methyl methacrylate) (PMMA) and polyethylene (PE)) under shear flow, and reported that the shear stress and the slipping modes can be changed by the experimental conditions. In this study, the effects of surface roughness of the substrate on the behaviors of PMMA and PE under shear flow are investigated based on molecular dynamics (MD) simulation.

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We have successfully developed reduction method of friction of metal oxide coatings with crystal preferred orientation to generate piezoelectric effect using a combinatorial sputter coating system for bea ring balls. Bearing with ZnO coated balls inside shows about half lower rotation friction than bearing without ZnO coated balls with friction test during high speed rotation and is expected an advanc ed ball bearing system in the near future.

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Tribological properties of glass based lubricant for forging nickel based high temperature alloys are important fo fabricate smoooth and high quality surface of alloys. We have prepared a high temperature tribology tester to measure friction coefficient of glass based lubricant under very high pressure using alumina based plate and alumina probe and evaluated the effect of temperature and pressure on friction.

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We have developed anodized aluminium film with thick sealing layer for high corrosion resistance of the aluminum used for Semiconductor etching equipment.We developed anodized aluminium film with thick sealing layer where large area processing is possible.I report on the surface characteristics of this practical anodized aluminium film with thick sealing layer

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[in Japanese]

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For volume reduction and recycling of radioactive contaminated soil, increasing quality of compound produced from the soil is important. Among minerals in soil, it has been reported for weathered biotite that Cs-desorption and crystal growth is realized by alkali salt, and so, controlling of the crystal growth has been set as next challenge. In this study, therefore, we investigated crystal growth from phyllosilicate minerals such as biotite with higher crystallinity by means of micro-Raman spectroscopy.

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Ti-6Al-4V alloy attracting attention as a biomaterial features excellent mechanical properties and corrosion resistance, and super plasticity. However, this alloy contains aluminum and vanadium liable to do serious harm to human bodies, so actual use will require prevention of direct contact with biological tissues. On the other hand, prostheses or implants made of pure titanium exhibit excellent biocompatibility. Therefore coating of the alloy substrates with pure titanium film by sputtering was examined, in order to improve the biocompatibility of the alloy. According to AES in-depth profiles and EPMA (WDS) analysis, neither aluminum nor vanadium was detected in the surface layer of titanium-coated specimens. Results of in-vitro cytotoxity tests revealed that the cytocompatibility of the alloy could be improved by coating with the pure titanium film. Thus the titanium alloy could be successfully coated with pure titanium film.

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GaN enables low power consuming and high temperature operatable electronic.Recently CARE which utilizes catalyst etching reaction in water can form flat GaN surface in atomic level and it is going to be applied to fabrication of devices. In this presentation, etching processes and catalyst effects in CARE are investigated at the atomic level by means of first-principles calculations.The water dissociative adsorption process and the role of Pt catalyst on GaN surface were analyzed.

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The effect of the load on the C₆₀ molecular bearing structure (graphene / single C₆₀ molecule / graphene interface) is investigated by molecular mechanics simulation. As a result, it was clarified that the lateral stiffness evaluated by the friction force microscopy (FFM) has a load dependence, and the load is nearly proportional to the tilting angle. Therefore, the lateral stiffness can be described as a function of a tilting angle of C₆₀ molecule. Thus, this research is expected to be useful for the control of the superlubricity of the C₆₀ molecular bearings and the molecular structure at the interface.

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Atomic-scale peeling of graphene has been studied by using both molecular mechanics simulation and atomic force microscopy (AFM) measurement. However, the simulated results could not be directly compared with the measured data, because the effect of AFM measurement system was not included sufficiently and furthermore the simulated graphene sheet was much smaller than the measured one. In this study, the peeling of graphene was modeled focusing on the adhesive characteristics of the peeling process, and then the change of the peeling characteristics with increasing the size of the graphene sheet is discussed considering the effect of mechanical system of AFM.

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In this study, several fullerenes adsorbed onto a graphene sheet are scanned by the graphene flake tip assumed as an AFM tip using molecular mechanics simulation. The vertical force acting on the flake tip is calculated at each scan position and the two-dimensional force maps will be reported. Moreover, it will be discussed whether C60 and C70 can be distinguished with each other by AFM if they are intermixed on a graphene sheet.

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It has been pointed out that the atomic-scale friction of graphene for the commensurate scan direction shows properties different from that for the incommensurate scan direction between the graphene and the graphite substrate surface. In this work, the atomic-scale sliding process is simulated by molecular mechanics simulation to investigate the lateral force and the real contact area at the graphene/graphite interface. Anisotropy of atomic-scale friction of graphene is discussed based on the moire patterns appeared at the interface of the real contact area regarded as the structural transition from the commensurate to the incommensurate stacking.

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Atomic-scale superlubricity of the molecular bearing (C₆₀,C₂₁/graphene interface) has been investigated by molecular mechanics simulation in order to control the nanoscale friction. In this work, we focused on the commensurate scan direction, and studied the influence of the deformation of the intercalated molecules at interface on energy dissipation. The relation between the total energy and molecular deformation is clarified by separating the non-bonding interaction energy between the molecule and the graphene and the elastic energy of the molecule.

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[in Japanese]

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Molecular motor using multi-walled CNT (MWCNT) has been so far studied both experimentally and theoretically because of its bearing effect. It makes rotational and translational motions simultaneously. In this work, the possibility to control either the translational or the rotational motion is studied based on the analysis of the total potential energy surface using molecular mechanics simulation. Here the outer CNT length and the loading force acting on the stator are chosen as parameters. It is clarified that these parameters enable CNT motor to control either the rotational or the translational motion.

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[in Japanese]

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[in Japanese]

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[in Japanese]

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[in Japanese]

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Transition metal dichalcogenides (TMDCs) have been investigated intensively as materials for novel device. In addition, they may be promising materials for spintronic devices when they are combined with magnetic atoms. Keeping this in minds, we examine the magnetic properties of magnetic-metal-adsorbed TMDCs using first-principles calculations based on the density functional theory. In particular, we explore the possibility of controlling their magnetic properties by tensile strain.

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[in Japanese]

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SnSe is a layered chalcogenide with an orthorhombic structure that works as
a thermoelectric material with high figure-of-merit (ZT) value, which is
related with the carrier concentration. It has been reported that Sn vacancies
in SnSe give rise to p-type characteristics. In this study, we investigated the
effect of defects on the surface atomic and the electronic structures by
low-temperature scanning tunneling microscopy (STM).

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[in Japanese]

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[in Japanese]

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[in Japanese]

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Regarding the growing importance of grain boundary phases and the interfaces of permanent magnets, we targeted the amorphous Nd-Fe phases appearing at the grain boundaries of Nd-based permanent magnets. In the presentation, we discuss the relationship between nearest-neighbor networks and exchange coupling in the amorphous alloys, and the structural and magnetic properties at the interfaces between crystalline and amorphous phases.

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It has been known that monolayer h-BN grown on Ni is chemically bound to the Ni substrate due to orbital hybridization. However, we succeeded in growing quasi-free-standing monolayer h-BN on Ni. The h-BN/Ni system was extensively studied by XAS, XES, XPS, and PEEM. Especially, the first observation of takeoff angle dependence of XES from monolayer h-BN is presented.

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