Glancing-angle deposition method was successfully applied in three reactive plasma processes (reactive ion plating, reactive sputtering and reactive evaporation) in order to fabricate indium-nitride films with microvillus-like isolated nanocolumnar structures. We found that the shape controllability of the isolated nanocolumns could partly be ascribed to the preferred orientation of the crystalline nanocolumns. The microvillus-like structures made the electrochromic color change of the indium-nitride films much larger.

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  We demonstrate the growth of unusual metal nanowhiskers by glancing angle deposition on a high temperature (HT-GLAD) substrate, while the usual nanocolumnar structures completely disappear due to accelerated surface diffusion. HT-GLAD is essential for the nucleation of the nanowhiskers and efficient supply of metal atoms on the side surface of the vertically growing nanowhiskers. HT-GLAD will, for the first time, reveal the mechanisms for the vapor growth of metal whiskers and be useful to produce high-quality metal nanowires for novel device elements.

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  Uniform carbon coating on nanochannels of an anodic aluminum oxide film drastically changes its optical property and, as a result, the resulting carbon-coated film exhibits brilliant colors. The carbon deposited on the inner walls of the nanochannels plays a major role in this phenomenon. In addition, the coating makes the channel walls electro-conductive, hydrophobic and much more chemically stable. These characteristics are never found in the original film. Owing to such peculiar properties, the coated film is more attractive as a template for the production of nanomaterials, because the electro-conductivity enables the electro-deposition of metal on the inner walls of the nanochannels and the hydrothermal synthesis inside the nanochannels is also possible due to the chemical inertness.

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  The fabrication of functional surfaces with fine ordered structures from submicron to nanometer scales has attracted increasing attention due to its application in various fields. In the present report, fabrication of several types of functional ordered surfaces based on the highly ordered anodic porous alumina are described. Anodic porous alumina, which is formed by anodization of Al in acidic electrolyte, is a typical self-ordered material and is promising candidate for the nanofabrication. As typical example of the fabrication of ordered surfaces, the highly ordered structures of the anodic porous alumina could be applied to the mask processes, in which the metal dot arrays or hole arrays are formed on the substrates. Some typical examples of the application of the obtained ordered surfaces were also described

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  The X-ray lens is a key technology for the X-ray microscopy at synchrotron radiation (SR) facility. Various types of the focusing optics (lens) for high-energy X-rays have been developed up to now. A multilayer Fresnel zone plate (FZP), which consists of periodic multilayer structure, is one of promising optics. In this review paper, firstly the recent status of various focusing optics for high-energy SR X-rays is described. And next, some of our representative results of the multilayer FZP with high diffraction efficiency and the X-ray microscopic image are shown.

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  Conspicuous metallic blue of Morpho butterflies is well known and attract interest because it is a brilliant luster of natural beings. The blue is produced by their proteins, which are almost transparent without pigment. The origin of the coloration with high reflectivity (>~60%) is then attributed to an interference effect based on a periodic structure. However, the interference contradicts the blue that is maintained in too wide angular range (>±40° from the normal). This mystery has recently been explained with a specific multilayer, which is a fine combination of regular and random structures at nanometer scale. We proved this hypothesis successfully by emulating the 3D structures by deposition of multilayer film on a nano-patterned substrate. Such artificial structural color can be applied to various industries, because it makes colors qualitatively impossible by pigment, and resistant to fading due to chemical change over longtime. Also we developed a high throughput nano-patterning process by use of nano-imprinting method, and succeeded in controlling the optical properties both in angular and wavelength distribution.

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  The characteristics of a cluster beam interaction with a solid target are reviewed from the viewpoint of computer simulation. The similarity and dissimilarity of irradiation effects between single and cluster ion beams are the main emphasis of the review. The speed-range of a projectile studied is below the Bethe range (v₁≤v₀ Z₁) but not so low, where electronic energy loss is significant. Because of the multiple collisions (in time and space) a classical molecular dynamic simulation is useful, whereas the multiplicity in energy is more significant for a molecular projectile. Here the collision stage of energy transfer from a projectile to target during the collision stage is separated from the succeeding relaxation stage. The multiplicity in the collision stage can cause molecular effects, however they are not always so significant. In the relaxation stage a somewhat enhanced effect can occur when the locally deposited energy exceeds a certain level.

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  A new ion source using massive molecules called metal cluster complexes has been developed. Metal cluster complexes are chemically-synthesized organometallic compounds, which have a wide range of chemical compositions with high molecular weight. The ion source is compact enough to be installed in commonly used secondary ion mass spectrometry (SIMS) systems. Using the ion source, sputtering characteristics of silicon bombarded with normally incident Ir₄(CO)₇⁺ ions were investigated. Experimental results showed that the sputtering yield at 10 keV was 36, which is higher than that with Ar⁺ ions by a factor of 24. In addition, SIMS analyses of boron-delta-doped silicon samples and organic films of poly(methyl methacrylate) (PMMA) were performed. Compared with conventional O₂⁺ ion beams, Ir₄(CO)₇⁺ ion beams improved depth resolution by a factor of 2.5 at the same irradiation conditions; the highest depth resolution of 0.9 nm was obtained at 5 keV, 45° with oxygen flooding of 1.3×10^-4 Pa. Furthermore, experimental results confirmed that Ir₄(CO)₇⁺ ion beams significantly enhanced secondary ion intensity in high-mass region.

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  A new type of cluster SIMS, named as electrospray droplet impact (EDI), has been developed in our laboratory. It was found that peptides deposited on the stainless steel substrate were ionized/desorbed without the accumulation of radiation products. The organic samples with film thickness thinner than 10 monolayers are desorbed/ionized with little damage underneath the surface. In general, rather strong negative ions as well as positive ions are generated. The mechanism for the ionization/desorption in EDI is much less complicated than those for MALDI and SIMS due to the fact that only very thin sample layers take part in the shock-wave excited selvedge and higher-order side reactions are largely suppressed.

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  The post UV-O₃ treatment of as-deposited CVD-SiO₂ film using Tetraethoxysilane gas was carried out to improve the dielectric properties of the film at lower temperature than 450°C. Application of highly-concentrated (>90 vol.%) ozone under irradiation of UV light (210nm<λ<450 nm) resulted in the improvement of the film properties including the dielectric constant, etching endurance against buffered HF, and insulating properties (leakage current through the film) for the process temperature as low as 100°C. Because these improvements were reduced at absence of either UV light or highly concentrated ozone, the diffusion of electronically excited oxygen atom generation by photodissociation of ozone into the film is considered to play a key role to the improvement of the film properties.

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  We have developed a high efficiency ozone killer for reduced pressure and high concentration ozone using ultra-violet (UV) light irradiation to ozone gas. The highly concentrated ozone gas (∼100%) of 30-110 Pa with a flow rate of 50 sccm^† can be decomposed to the concentration as low as 5% by UV light (200 nm-300 nm, 15 mW/cm²) irradiation. However, the residual ozone gas concentration increases the supplied ozone flow rate, since ozone molecule must stay in the ozone killer to absorb a UV photon. The photo-type ozone killer can be practically applied to actual processes by optimizing the dimension of the killer for a given pressure and gas flow rate.

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