Nano-crystalline CeO2 was synthesized by the mechanical milling and subsequent heat-treatment from the mixture of Ce(OH)4 as precursor, and NaCl as diluent. The diluent provided diffusion barrier during milling and heat-treatment, which was easily dissolved out by deionized water. The size of crystallite and the strain variance of CeO2 were depended on the temperature and heat-treatment time: increased with the temperature (400~700oC) and time (1~24 hours) increasing, and saturated near at 20nm in size owing to the densification of diluent. The synthesized nano-crystalline CeO2 powder was applied as an abrasive in CMP (Chemical Mechanical Planarization) slurry. When blanket-type SiO2 and Si3N4 wafers were polished with the slurries, the removal rates (RR) of SiO2 and Si3N4 wafers and selectivities (RRSiO2/RRSi3N4) were influenced by synthetic condition of abrasive, the suspension stability and the pHs of slurries.

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We report on the distribution of mixed self-assembled monolayers (SAMs) composed of biotinylated and diluent alkylthiolates for streptavidin immobilization. Two thiol derivatives, 11-mercapto-1-undecanol (MUOH) and 11-mercaptoundecanoic-(8-biotinylamido-3,6-dioxaoctyl) amide (MBDA), were employed for mixed SAM. These thiols formed self-assembled monolayer without local domain, and streptavidins were immobilized onto biotinylated gold surface without nonspecific binding. In order to find the optimized condition of immobilization of streptavidin, we controlled the mixing ratio of two kind thiols by colorimetric detection assay, and the immobilization was characterized by atomic force microscopy (AFM), scanning tunneling microscopy (STM), and ellipsometer.

NiO/YSZ composite powder with 70 wt% of NiO was prepared by surface modification of ~30 nm YSZ with Ni precursors. As Ni precursors, acidic nickel nitrate and basic nickel carbonate were employed. By varying the ratio of Ni precursors, substantially different particle sizes were obtained. Their Ni/YSZ cermets also showed substantially different microstructures and porosities. Effects of combination of Ni precursors on Ni/YSZ cermets were studied by using XRD, zetapotential, and SEM.

CuO/GDC composite powder with 50 wt% of CuO was prepared by surface modification of ~60 nm GDC powder with Cu precursors. Since copper oxide melts at lower temperature than GDC sintering temperature, fabrication procedure was modified by inducing infiltration of molten copper oxide via capillary force and then followed by heat treatment at ~1000 °C . Surface modification was carried out with a MgO sol to suppress agglomeration of GDC. Such prepared Cu/GDC cermets showed uniform microstructure and excellent electric conductivity of ~6000 S/cm for the Cu/GDC cermet and ~10000 S/cm for the modified one at 800°C.