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941.
Embedded ferroelectric memory technology with completely encapsulated hydrogen barrier structure 总被引:2,自引:0,他引:2
Nagano Y. Mikawa T. Kutsunai T. Natsume S. Tatsunari T. Ito T. Noma A. Nasu T. Hayashi S. Hirano H. Gohou Y. Judai Y. Fujii E. 《Semiconductor Manufacturing, IEEE Transactions on》2005,18(1):49-54
A 0.18-/spl mu/m system LSI embedded ferroelectric memory (FeRAM) operating at a very low voltage has been developed for the first time. The low-voltage operation has been attained by newly developed stacked ferroelectric capacitors completely encapsulated by hydrogen barriers, which enable us to eliminate hydrogen reduction of the ferroelectric thin film during the back end of the line process including FSG, tungsten CVD (W-CVD), and plasma CVD SiN (p-SiN) passivation. A fabricated 1-Mbit one-transistor one-capacitor SrBi/sub 2/(Ta/sub x/Nb/sub 1-x/)/sub 2/O/sub 9/ (SBTN)-based embedded FeRAM operates at a low voltage of 1.1 V and ensures the endurance cycles up to 10/sup 12/ at 85/spl deg/C and the data retention time up to 1000 h at 125/spl deg/C, which is the most promising for mass production of 0.18-/spl mu/m low-power system LSI-embedded FeRAM and beyond. 相似文献
942.
Ayahiko Niimi Masaaki Wada Kei Ito Masashi Toda Katsumori Hatanaka Osamu Konishi 《Artificial Life and Robotics》2008,13(1):264-270
In this paper, we propose the system that combines the sensor network with the mail delivery system to construct the system
that observes an environmental change of the broiler-house. As a result of hearing of the producer, the environment system
needs to able to be observed some broiler-houses, to inspect the summary data from the cellular phone, and to transmit the
warning mail in a rapid temperature change. A basic part of the system is a sensor network by the sensor module that we developed.
Only the sensor modules are put in the each broiler-house, and the network by wireless LAN communication is constructed, because
the system needs to watch of two or more broiler-houses, and it is difficult to setup a large-scale system at the broiler-house.
The always-connected high-speed Internet is preferable to accumulate, to process data, and to offer it to the user in a comprehensible
form. But, it is difficult to build always-connected high-speed Internet at the chicken farm which is used by experiment.
The server is set up in the remote place, and we propose the system that delivers data from the chicken farm with mail. The
verification of the effectiveness of the proposed system and the problem are examined by actually setting up the system that
proposes it in the broiler-house, and operating it.
This work was presented in part at the 13th International Symposium on Artificial Life and Robotics, Oita, Japan, January
31–February 2, 2008 相似文献
943.
An ecosystem, especially a food web, is essentially characterized as a many-body system in which the members interact with
each other under the limitations of the energy and resources. We introduce a coevolutional population dynamics model for food
webs which contains energy-conserving interactions, energy dissipation, and rules for changing the degrees of freedom (extinction
and mutation). In this model, the diversity of the system increases spontaneously. The statistical properties of the system,
such as the distribution of the life time of the species, are also discussed.
This work was presented, in part, at the Sixth International Symposium on Artificial Life and Robotics, Tokyo, Japan, January
15–17, 2001 相似文献
944.
The resistive transition to the superconducting (SC) state in -(ET)2NH4Hg(SCN)4 was studied under magnetic fields applied parallel to the conducting plane. The SC state is divided into three regions: (1) temperature-dependent resistive region, (2) zero-resistive region, and (3) temperature-independent resistive region. We observed twofold symmetry in the resistance under an in-plane magnetic field near the midpoint of the SC transition, which indicates that the upper critical field 0
H
c2 has the same twofold symmetry. This in-plane anisotropy can be ascribed to the crystal structure. 相似文献
945.
Hashimoto T Morishita M Iwashita K Shimoi H Nakata Y Tsuji Y Ito K 《Journal of Bioscience and Bioengineering》1999,88(5):479-483
Beta-xylosidase production from a shoyu (soy sauce) koji mold, Aspergillus oryzae HL15, cultured in solid and liquid media was examined and some properties of the enzymes were studied. Three beta-xylosidases (Xy11, Xy12 and Xy13) were easily extracted with 0.5% NaCl from a solid medium and purified homogeneously on SDS-PAGE by chromatography. On the other hand, in a liquid medium, A. oryzae HL15 produced mainly cell-wall-bound beta-xylosidases which could not be extracted with 0.5% NaCl or any detergent. Cell-wall-bound beta-xylosidases, Xy11-CB and Xy12-CB, were liberated by digestion of mycelia with Yatalase and purified to a homogeneous state on SDS-PAGE by HPLC column chromatography. Four beta-xylosidases (Xy11, Xy12, Xy11-CB and Xy12-CB) exhibited not only high activity at high NaCl concentrations, but also similar properties; on the other hand, Xy13 differed in terms of thermostability and halophilic properties. The salt tolerance of beta-xylosidases in A. oryzae suggests that these enzymes are highly active and involved in releasing xylose in shoyu moromi mash. 相似文献
946.
Ito Teruo Yamaguchi Tadashi Ueda Ryuzo Mochizuki Tahuro Takata Sigeo 《Industry Applications, IEEE Transactions on》1983,(2):206-210
The field orientation control of current source inverter (CSI) drive induction motor (IM) systems has been known to give an induction motor dc motorlike characteristics. As a result of an analysis, the characteristic of these systems does not necessarily coincide with that of dc motor systems, especially with light loads. The result of the analysis is verified by experiments. 相似文献
947.
Eisuke Yamamoto Kosuke Fujihara Yuma Takezaki Kentaro Ito Yue Shi Makoto Kobayashi Minoru Osada 《Small (Weinheim an der Bergstrasse, Germany)》2023,19(22):2370159
Recent progress in 2D materials has initiated new fields of molecularly thin amorphous materials with mysterious properties and structures. However, designed synthesis of molecularly thin amorphous silica still remains a challenge; whether free-standing molecularly thin amorphous silica nanosheets can exist is unclear. Here, this issue is addressed by using a new chemical protocol; solid-state surfactant lamellae with ordered alkyl-chain arrangements can serve as superior templates guiding free-standing amorphous silica nanosheets. Simple sonication of the lamellar hybrids allows exfoliation into monolayer amorphous silica nanosheets with 0.9 nm thickness. In addition, the nanosheets show the distinctive feature of high colloidal stability that enables atomic layer engineering of silica nanocoatings and dielectric nanofilms. The approach may shed new light on the properties and applications of old silica. 相似文献
948.
Tamon Ozaki Noriyuki Ito Jiro Kawai Shuhei Nakamura 《Electrical Engineering in Japan》2004,148(3):7-14
By dividing a water‐treed XLPE sheet sample of 1 mm thickness into a nondegraded region and a water‐treed one, relative permittivity and AC conductivity σAC2 of the water‐treed region have been estimated using an equivalent circuit. The variation of and σAC2 with the length r of the water‐treed region has been discussed based on the Sillars model. It was concluded that the volume fraction of water in the water‐treed layer is in the range from 0.5% to 1.5% for the most‐degraded XLPE sheet, which depends on the ratio of axes of spheroids to which water‐filled voids and channels are compared. It was also concluded that the AC conductivity of water in the water‐treed region ranges from 3 × 10?3 S/m to 2 × 10?2 S/m. © 2004 Wiley Periodicals, Inc. Electr Eng Jpn, 148(3): 7–14, 2004; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.10332 相似文献
949.
Plant sterol and stanol esters are called "functional" compounds due to their hypocholesterolemic properties. The objective of this review is to update recent findings concerning the effect of phytosterols in the blood cholesterol, emphasizing the results from experimental and human studies. The hypocholesterolemic effect is observed with the intake of 2.5g/day of phytosterols or phytostanols. Daily intake, usually of stanols, for 4 weeks has shown to to be effective in lowering blood total- as well as LDL-cholesterol by about 10%. The mechanism of action in lowering blood cholesterol comes from their structural similarity to cholesterol, hence they act by competing with cholesterol at the luminal absorption site. The adverse effects of a high intake of phytosterols and phytostanols are the lower absorption of some liposoluble vitamins and antioxidants. 相似文献
950.
A. Sonehara T. Eguchi A. Sugizaki A. Kumano T. Ito T. Takahashi 《Journal of the Society for Information Display》2006,14(8):673-680
Abstract— Column spacers were manufactured by a roll‐to‐roll process for a flexible plastic substrate and an LCD prototype was demonstrated for the first time. The purpose of this paper is to obtain a stable cell gap for plastic LCDs by designing the column spacers. The optimum condition was derived for the properties of the column spacers parameters, such as the cross section, density, and hardness. As a result, we could determine the optimum elastic modulus of the column spacers needed in order to precisely maintain the cell gap of the LCD as well as that of conventional glass plates, resulting in a uniform display luminance. 相似文献