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The crystal structures of Ce 2 Zr 2 O 7 and bCe 2 Zr 2 O 7.5 were precisely determined by the Rietveld refinement of powder Xray diffraction data. The present refinement revealed that the structure of bCe 2 Zr 2 O 7.5 was formed by filling a half of oxygen vacancies of Ce 2 Zr 2 O 7 in the specific ordered manner. The oxygen vacancy site is divided into two equivalent sites, one of which is completely occupied, when the composition becomes Ce 2 Zr 2 O 7.5 . The formation of bCe 2 Zr 2 O 7.5 can be well explained on the basis of the argument that Zr 4{ ions tend to be 7fold coordination at low temperatures. The derived local atomic displacements associated with the oxygen absorption/release, particularly those of oxygen at the specific sites, could be a key issue to solve the reason why Ce 2 Zr 2 O 7{x exhibits the excellent property of oxygen release and absorption even at relatively lower tempera tures.

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In focused ion beam (FIB) fabrication of cross-sectional transmission electron microscopy (X-TEM) specimens, highly accelerated ion beams sometimes cause serious damage. The damage can be induced in both the specimen surface and the side walls. We used the X-TEM technique to investigate the sidewall damage in crystalline Si. The damaged layer was found to be about 20 nm thick in the case of 30-keV-FIB etching. We evaluated several techniques for reducing the damage, such as gas-assisted etching (GAE) with iodine, low-energy FIB etching, and cleaning by broad argon ion milling or by wet etching. The damage depth was 19 nm for GAE and 10 nm for 10 keV FIB etching, and was reduced to 7 nm by 3 keV argon ion milling with a beam current of 20 μA and a tilt angle between the beam and the specimen of 4°. Wet etching using a mixture of nitric and hydrofluoric acid removed most of the damaged layer. The effect of the damaged layer on TEM observation was also investigated, and it was shown that removal of the damaged layer results in a high-resolution TEM image.

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We developed low-resistivity transparent conductive films having the structure of indium-tin-oxide/silver/indium-tin-oxide (ITO/Ag/ITO). The thin silver film was sandwiched by ITO films. Our goal was to study the characteristics of the sandwich films and the display characteristics of simple-matrix liquid-crystal displays (LCDs) fabricated using the sandwich film. The electrical and optical characteristics of the sandwich films depended greatly on the thickness of the ITO and silver layers. Low resistivity and high transmittance were obtained when the film structure had a thickness of ITO/Ag/ITO: 40 nm/15 nm/40 nm. The simple-matrix LCD fabricated using a sandwich of ITO/Ag/ITO exhibited 27%–48% reduction in the level of crosstalk compared to the conventionally available simple-matrix LCDs fabricated using a single-layer ITO film; thus, the display performance was improved.