Growth mechanisms of nanometer-sized particles prepared by rf sputtering on silica glass layers were examined. Gold and gallium arsenide (GaAs) particles synthesized with varying sputtering times on a SiO2 sputtered layer were subsequently buried in a SiO2 film by sputtering a SiO2 target. Transmission electron microscopy showed that in both cases, with increasing sputtering time, the number density decreased and the distance between neighboring particles increased in the initial stage of the growth, which suggests that the particles migrate on the SiO2 surface and coalesce with each other as they grow. Differences of GaAs and gold particle formation suggest that the mobility of the GaAs particles is much larger than that of gold. The results suggest that the migration of nanoparticles is activated by the bond-formation energy released during the incorporation of precursors into growing particles.

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Mesoporous silica films have been synthesized as a single pore layer on silicon, germanium, and indium tin oxide substrates. The film structure consists of a hexagonal array of pores approximately 10nm in diameter, with 3nm wall thickness. The film thickness is controlled through ethanol dilution of the precursor solution, while the film structure is controlled through the acid content and relative humidity of the aging environment. Increasing acidity suppresses the condensation and polymerization kinetics in the film, while the water content of the aging environment increases the fluidity of the film prior to condensation and the curvature of the micelles. Higher acidity and relative humidity result in films that develop the thermodynamically stable phase, as would be predicted by the volume fraction of the block copolymer. Gold was sputter deposited onto mesoporous substrates, resulting in gold islands that are thermally more stable compared with those resulting from deposition on the bare substrate. The gold islands that deposit atop the mesoporous film can be easily removed, resulting in an array of isolated gold particles inside the pores. Furthermore, gold films deposited onto mesoporous silica films on germanium substrates show a dramatic increase in thermal stability against coarsening relative to particles on bare germanium. A sputter deposited gold grown and maintained at 550°C for many hours retain a grain size of approximately 10nm, while grains on bare germanium coarsen to larger than 100nm.

We found that surface protrusions of chemical vapor deposited TiN films are caused by reactions between copper contaminants and the silicon substrate. Depending on the size of the copper contaminant, two kinds of defects were formed: copper silicide (CuSi) and silicon dioxide. The silicon dioxide is formed because of the catalytic role of copper silicide. The defects grow both into and out of the silicon substrate. In the formation of copper silicide and silicon dioxide, copper, silicon, and oxygen are the major participating species.

Application of electro-statically extracted ink-jet technology was studied in dyeing processing of Oshima-tsumugi-mushiro. It is needed to dye about 1mm width on that mushiro. Our results showed that, electrostatically extracted ink-jet technology was effective for application to dyeing processing automatically.