A brief review is given on the basic features of organic field-effect transistors. We discuss the device structure, operation mechanism, and the unique properties of organic transistors and the difference between inorganic and organic devices. Recent advances in ambipolar transport in organic transistors are also addressed.

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  Organic light-emitting diodes involve several interfaces such as metal/organic, inorganic/organic and organic/organic layers. These interfaces significantly influence the performances, efficiency and lifetime, of the light-emitting diode. In this article, potential barriers for electrons and holes at the interfaces are discussed to control the charge injection and confinement. Insertion of a thin interlayer and doping of a donor or an acceptor into the organic layers at the interfaces reduce the potential barriers.

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  Fundamental principles and p-i-n junction concept of organic solar cells are described. Methods for improvement of conversion efficiency such as nanostructure design of co-deposited i-layer and high-purification of organic semiconductors are explained. Conversion efficiency exceeding 5% was observed. Cell operation for 1000 hours (42 days) was successfully accomplished.

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  The catalyst is a key technology for the realization of the sustainable society. The mechanism of heterogeneous catalyst is now being established based on the surface science approach which is supported by the ultrahigh vacuum techniques. Recently ambient pressure techniques are developing. The surface reaction can be now understood based on the machinery concepts of molcules and atoms. Spatiotemporal behavior of the surface atoms and molecules are revealed and what force works between the reactants. In the near future, the surface reaction can be controlled by physical means.

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  Chalcopyrite Cu(In, Ga)Se₂(CIGS) and related compounds belong to the semiconducting I-III-VI₂ materials family and are most promising thin film solar cells which have demonstrated up to 20% cell efficiencies and over 15% module efficiencies to date. Many CIGS companies in EU, US, and Japan have started several ten MW/year scale commercial production and have announced to increase their production capacities further within a couple of years. In this review, recent developments in highly efficient CIGS module technologies and issues to be solved for further development are discussed. Recent progress in the development of reliable alkali incorporation control techniques which is required to demonstrate high cell efficiencies from flexible CIGS cells fabricated on alkali-free substrates is also introduced. The mechanism behind the beneficial effects of alkali doping into CIGS absorber layers is also discussed.

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  A diamond-like carbon (DLC) film is characterized by its high hardness and low friction coefficient. These properties have quickly promoted their wide use in consumer products, such as tools, sliding components like dies, razor blades, and PET bottles. However, a DLC film has insufficient hardness. This has prevented its application to cutting tools for aluminum alloys of emerging demand. Therefore, this study addresses novel hard nanocarbon films, including high-density DLC films, nano-diamond films, and hybrid nano-diamond (HND) films as our new study objects. The hard nanocarbon films were formed on silicon wafers and tungsten carbide (WC) substrates. The film properties of hardness, composition, structure, and friction were analyzed. The result of high density DLC film hardness is high, 80-90 GPa, with a low friction coefficient of less than 0.1.
  We have coated these onto cutting tools, conducted aluminum-alloy cutting experiments, and estimated their applicability. Results have suggested the degradation of cutting ability because of aluminum built-up; the cutting distance with a tungsten carbide tip was 20 m without coating and 200 m with a DLC coating. The cutting distance was extended to 4000 m with HND coating, which was a DLC film and nano-diamond multilayer. A high-density DLC film might even be extended up to 10000 m, that is, its lifetime could be lengthened to 50 times that of an ordinary DLC film.

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  The growing concerns over global energy crisis and the phasing out of polyurethane foams blown with CFC-11, which has high Ozone Depletion Potential(ODP), have pushed thermal insulation technology to improve its efficiency. Vacuum Insulation Panel(VIP) has been regarded as a super thermal insulation material with a thermal resistance of about 5-10 times higher than conventional thermal insulation. Appropriate vacuum in VIP is one of the most important factors contributing to the long term heat insulation performance of VIP. In this paper, the researches on three factors, which influence internal pressure inside VIP, including gas and water vapor permeation through the barrier, gas absorption by getters and desiccants and outgassing of the kernel, were reviewed respectively. Following this, the research emphasis and suggestions, which should be paid attention to, were summarized.

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  After depositing an ultra-thin metallic Ti film by sputtering, we repeated the process of exposing the still active plasma gas for high-rate low-temperature deposition of a metal compound film, thereby successfully fabricating a thin film of TiO₂ with photocatalytic properties. The TiO₂ thin film produced using the present method exhibited approximately 15 times the deposition rate of DC reactive magnetron sputtering, yielding a crystalline structure using an unheated substrate (approximately 40°C).

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