resulting in relatively low data throughput. On the other hand, another type of the new memories based on a solid state We report a novel nonvolatile dual-layered electrolytic electrolyte [5], in which ions such as Ag+ or Cu+ move along resistance memory composed of a conductive Cu ion the applied field and form the conductive bridge in the activated layer and a thin insulator for the first time. An electrolyte, is a promising candidate from the viewpoints of ON/OFF mechanism of this new type memory is postulated high speed switching and low set/reset current. Previous as follows: Cu ions pierce through the insulator layer by studies on the memories, however, seem to show their applied electric field, the ions form a Cu conductive bridge in insufficient retention. the insulator layer, and this bridge dissolves back to the ion To realize both high speed switching and sufficient activated layer when the field is reversed. The 4 kbit memory retention, we have newly developed a dual-layered array with IT-IR cell structure was fabricated based on 180 electrolytic resistance memory utilizing Cu conductive bridge nm CMOS process. Set/reset pulses were 5 ns, 110 gtA and 1 combined with a thin insulator. ns, 125 gA, respectively. Those conditions provide large set/reset resistance ratio of over 2 orders of magnitude and Memory Design satisfactory retention. Essential characteristics for high capacity memories including superb scalability down to 20In a solid state electrolytic memory, metallic ions such as nmo, sufficient endurance up to 107 cycles and preliminary Ag+ or Cu+ play an essential role in fast forming a conductive data for 4-level memory are also presented. These bridge when the electric field is applied. But without the field, characteristics promise the memory being the next generation the bridge should steadfastly keep the shape for the data high capacity nonvolatile memory even before the scaling retention. It seems hard to solve these incompatible limitation of flash memories is encountered. characteristics within a single layer. Therefore we divided the role into respective two layers: the conductive ion activated Introduction layer and the resistance change layer of the insulator as shown in Fig. 1. The resistance change layer is thin enough An imminent scaling limit of flash memories accelerates for the activated ions to pierce through the layer rapidly in the search for the new memories and so far several types of the electric field. The conductive bridge is stable in the layer resistive memories are proposed, such as phase change when no electric field is applied. When the reverse field is memory [1, 2], oxide base resistance change memory [3, 4] applied, the bridge is dissolved back to the ion layer, where and so on. However, each memory seems to have inherent both the electric field and joule heat are thought to be main drawbacks such as large reset current and/or slow set speed, driving forces. Because the insulator layer is thin enough, o o a %^o Cu od 1 l z | CT e | og g uC Gd Cu-Te base conz u...

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Supported Pd−Au alloy catalysts were developed for the highly efficient and selective hydrosilylation of α,β-unsaturated ketones and alkynes. The Pd/Au atomic ratio of the Pd−Au alloy and the supporting material affected the catalytic activity, and supported Pd−Au alloy nanoparticles with a low Pd/Au atomic ratio functioned as highly active heterogeneous catalysts under mild reaction conditions. Structural characterization of supported Pd−Au alloy catalysts by X-ray diffraction, X-ray absorption spectroscopy (XAS), and transmission electron microscopy revealed the formation of random Pd−Au alloy nanoparticles with a uniform size of around 3 nm on the support. Furthermore, XAS and X-ray photoelectron spectroscopy elucidated the charge transfer from Pd to Au and the formation of isolated single Pd atoms in random Pd−Au alloys with a low Pd/Au ratio, which enabled efficient hydrosilylation of a variety of substrates under mild reaction conditions.

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Fluorinated amorphous carbon thin films (a-C:F) for use as low-dielectric-constant interlayer dielectrics are deposited by helicon-wave plasma enhanced chemical vapor deposition. To improve their thermal stability, the feasibility of adjusting the fluorine-to-carbon (F/C) ratio by changing the deposition pressure was investigated. Decreasing the pressure increased the dissociation of a source fluorocarbon material in the plasma and decreased the F/C ratio of the deposited film. Both the thermal stability and the dielectric constant of the a-C:F films were increased as the F/C ratio was decreased. Thus, there is a tradeoff relationship between a low dielectric constant and high thermal stability and the tradeoff could be optimized by the pressure during deposition. The mechanism of the pressure dependency of the dielectric constant of a-C:F films was investigated by quantifying the contribution of each polarization and found that a decrease in the dielectric constant of a-C:F films can be attributed to decreases in the orientational and electronic polarizations.

Fluorinated amorphous carbon films were proposed as low dielectric constant interlayer dielectrics for ultralarge scale integration circuits. The films were deposited by plasma enhanced chemical vapor deposition with CH4 and CF4 in a parallel plate rf (13.56 MHz) reactor. The dielectric constant of the amorphous carbon films deposited with CH4 was increased with increases in rf power. The addition of CF4 to CH4 raised the deposition rate and reduced the dielectric constant. At an rf power of 200 W, and at a flow rate of 47 sccm for CF4 and 3 sccm for CH4, the dielectric constant of the fluorinated amorphous carbon films was 2.1.

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