The importance of interface and bulk transport mechanisms on the leakage current of high dielectric constant thin film capacitors is examined by deriving an equation for the J–VA characteristic of a capacitor that includes the transport mechanisms of thermionic emission (TE), thermionic field emission (TFE), and carrier drift–diffusion (DD). The current is controlled by the slowest of three effective velocity parameters v1md, vD, and ṽ2dm characterizing electron injection into the dielectric at the cathode by TE and TFE, carrier DD in the film bulk, and electron ejection from the dielectric at the anode by TE and TFE, respectively. The effective velocity parameters are evaluated for a Pt/BST/Pt thin film capacitor that has been exposed to forming gas and it is shown that the dominant transport mechanism is interface limited TFE from the cathode with negligible influence of carrier transport by DD in the film bulk. Implications of these results on existing transport calculations for high dielectric constant thin film capacitors are discussed.

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The effect of several different aluminum‐containing ceramic additions to borosilicate glass on suppressing cris‐tobalite precipitation has been examined. The results showed that mullite or aluminum nitride suppresses cristo‐balite formation more effectively than alumina or spinel. Although both follow a simple rule of mixtures, glass/mullite composites can be fabricated with lower dielectric constants than glass/alumina composites, while maintaining a thermal expansion coefficient close to Si. Electron micro‐analysis using X‐ray energy dispersive spectroscope showed that the measured interdiffusion coefficient between alumina and glass is in good agreement with the data which have already been published.

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The shrinking behavior of Cu/ceramic circuit boards as it applies to controlling dimensional tolerances was studied. This report includes the shrinking behavior of ceramics and copper and of the Cu/ceramic interface.

Powder X-ray diffraction measurements were taken in the R2-x Ce x CuO4-δ (R=Pr, Nd, Sm, Eu and Gd) system. Rietveld refinement of these structures was performed assuming that the space group was 14/mmm. The lattice constant and rare earth metal location were determined to study the electrostatic effects of T'-phase materials. We found that the difference in the Madelung site potential, ΔV (V R-V Cu), as well as T c has a peak for the Cu-O bond length. These data suggest that the carrier concentration is not constant in T'-phase materials and that changes in the carrier concentration influence T c in these materials.

We examined the effect of Ca2PbO4 addition on superconductivity in a Bi-Sr-Cu-O system. We determined that Ca2PbO4 is formed in Bi-Pb-Sr-Ca-Cu-O at temperatures lower than 750°C on the basis of powder X-ray diffraction and micro-Raman scattering. A high-T c phase was synthesized by adding Ca2PbO4 to the Bi-Sr-Cu-O system which has a single CuO layer. It seems that the synthesis process of the high-T c phase is based on a reaction between the low-T c structure and Ca2+ in the liquid phase which is caused by decomposition of Ca2PbO4 at 822°C.

Arrays of lead lanthanum zirconate titanate pillars were fabricated on niobium-doped (001) strontium titanate substrates using a chemical solution deposition method with resist molds. Periodic arrays of submicron ferroelectric pillars with high crystallinity are required to produce high-quality tunable photonic-crystal devices. The relationship between the crystallinity and width of the pillars was investigated. The highest crystallinity was obtained at a width of 0.67μm. All the pillars exhibited ferroelectric strain. Since this width is in the order of that of optical wavelengths, this process and the periodic structures produced have potential applications in fabricating two-dimensional tunable photonic crystals.