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991.
Tada M. Tamura T. Ito F. Ohtake H. Narihiro M. Tagami M. Ueki M. Hijioka K. Abe M. Inoue N. Takeuchi T. Saito S. Onodera T. Furutake N. Arai K. Sekine M. Suzuki M. Hayashi Y. 《Electron Devices, IEEE Transactions on》2006,53(5):1169-1179
Robust porous low-k/Cu interconnects have been developed for 65-nm-node ultralarge-scale integrations (ULSIs) with 180-nm/200-nm pitched lines and 100-nm diameter vias in a single damascene architecture. A porous plasma-enhanced chemical vapor deposition (PECVD)-SiOCH film (k=2.6) with subnanometer pores is introduced into the intermetal dielectrics on the interlayer dielectrics of a rigid PECVD-SiOCH film (k=2.9). This porous-on-rigid hybrid SiOCH structure achieves a 35% reduction in interline capacitance per grid in the 65-nm-node interconnect compared to that in a 90-nm-node interconnect with a fully rigid SiOCH. A via resistance of 9.7 /spl Omega/ was obtained in 100-nm diameter vias. Interconnect reliability, such as electromigration, and stress-induced voiding were retained with interface modification technologies. One of the key breakthroughs was a special liner technique to maintain dielectric reliability between the narrow-pitched lines. The porous surface on the trench-etched sidewall was covered with an ultrathin plasma-polymerized benzocyclobuten liner (k=2.7), thus enhancing interline time-dependent dielectric breakdown reliability. The introduction of a porous material and the control of the sidewall are essential for 65-nm-node and beyond scaled-down ULSIs to ensure high levels of reliability. 相似文献
992.
Nii K. Tsukamoto Y. Yoshizawa T. Imaoka S. Yamagami Y. Suzuki T. Shibayama A. Makino H. Iwade S. 《Solid-State Circuits, IEEE Journal of》2004,39(4):684-693
In sub-100-nm generation, gate-tunneling leakage current increases and dominates the total standby leakage current of LSIs based on decreasing gate-oxide thickness. Showing that the gate leakage current is effectively reduced by lowering the gate voltage, we propose a local dc level control (LDLC) for SRAM cell arrays and an automatic gate leakage suppression driver (AGLSD) for peripheral circuits. We designed and fabricated a 32-kB 1-port SRAM using 90-nm CMOS technology. The six-transistor SRAM cell size is 1.25 /spl mu/m/sup 2/. Evaluation shows that the standby current of 32-kB SRAM is 1.2 /spl mu/A at 1.2 V and room temperature. It is reduced to 7.5% of conventional SRAM. 相似文献
993.
Supachai Ngamsinlapasathian Sorapong Pavasupree Yoshikazu Suzuki Susumu Yoshikawa 《Solar Energy Materials & Solar Cells》2006,90(18-19):3187-3192
Nanocrystalline mesoporous titania was obtained by surfactant-assisted templating method using tetraisopropyl orthotitanate modified with acethylacetone and laurylamine hydrochloride as template. This material was applied for the electrode of dye-sensitized solar cell. The mesoporous TiO2 (MP-TiO2) cells exhibited higher short-circuit photocurrent density and solar energy conversion efficiency compared to P25 (a typical commercial titania powder) cells. The incident photon to current conversion efficiency spectrum of MP-TiO2 can be improved by using the cell made with 5% P25 additive. Double-layer titania cells were fabricated to further improve cell performance by increasing the film thickness and light scattering. The solar conversion efficiency up to 8.06% was obtained by using the double-layer titania cell sintered at 450 °C for 2 h. 相似文献
994.
Takeshi Mikami Ken Fukushi Miki Ishitani Kouki Ishitani Shigeo Suzuki Masuko Suzuki 《Lipids》1991,26(12):1404-1407
A neutral subfraction of mannan of bakers' yeast (WNM) was found to show a lethal effect in mice when administered intravenously.
Symptoms caused by intravenous (i.v.) administration of WNM resembled those resulting from the administration of platelet-activating
factor (PAF). CV-3988 and ONO-6240, selective PAF antagonists, prevented hypotension and death caused by the administration
of WNM or PAF. A β-adrenoceptor agonist was shown to prevent death caused by WNM, whereas propranolol increased the lethal
activity of WNM. Intravenous administration of WNM into mice produced PAF in gall bladder fluid which was determined by platelet
aggregation assay. The findings indicate that WNM is able to induce PAF in mice and that the resultant PAF may participate
in the WNM-induced lethal activity observed in mice. 相似文献
995.
Creep strength of magnesium-based alloys 总被引:5,自引:0,他引:5
Maruyama Kouichi Suzuki Mayumi Sato Hiroyuki 《Metallurgical and Materials Transactions A》2002,33(13):875-882
The high-temperature creep resistance of magnesium alloys was discussed, with special reference to Mg-Al and Mg-Y alloys.
Mg-Al solid-solution alloys are superior to Al-Mg solid-solution alloys in terms of creep resistance. This is attributed to
the high internal stress typical of an hcp structure having only two independent basal slip systems. Although magnesium has
a smaller shear modulus than aluminum, the inherent creep resistance of Mg alloys is better than that of Al alloys. The creep
resistance of Mg alloys is improved substantially by the addition of Y. Solid-solution hardening is the principal mechanism
of the strengthening, but the details of the mechanism have not been elucidated yet. Forest dislocation hardening in concentrated
alloys and dynamic precipitation in a Mg-2.4 pct Y alloy also contribute to the strengthening. An addition of a very small
amount of Zn raises the dislocation density and significantly improves the creep resistance of Mg-Y alloys.
This article is based on a presentation made in the symposium entitled “Defect Properties and Mechanical Behavior of HCP Metals
and Alloys” at the TMS Annual Meeting, February 11–15, 2001, in New Orleans, Louisiana, under the auspices of the following
ASM committees: Materials Science Critical Technology Sector, Structural Materials Division, Electronic, Magnetic & Photonic
Materials Division, Chemistry & Physics of Materials Committee, Joint Nuclear Materials Committee, and Titanium Committee. 相似文献
996.
Sasaki Y. Tanosaki S. Suzuki J. Yuasa T. Taniguchi H. Devaraj B. Akatsuka T. 《IEEE sensors journal》2003,3(5):658-667
We proposed and developed a novel transillumination laser CT imaging system, using optical fibers, based on the optical heterodyne detection method for biomedical use. The use of optical fibers enables portability and robustness against environmental changes such as varying temperature, air-flow shifts, and unexpected vibrations. In addition, motion-artifact-free images can be obtained with the present system as measurements can be performed with the object fixed. We experimentally investigate in detail the fundamental imaging properties of the system, that has a spatial resolution of 500 /spl mu/m, a dynamic range of approximately 110 dB, and a minimum-detectable-optical power of 10/sup -14/ W as a result of the excellent properties of the heterodyne detection. Based on experimental observations, the proposed system can reconstruct tomographic images of highly scattering objects in the transillumination mode, similar to X-ray CT, at sub-millimeter spatial resolution and can derive quantitative information from the images. Finally, we experimentally demonstrate the first in-situ tomographic images of plants using the fiber-optic-based laser CT system. 相似文献
997.
Xingyang Wu Masahiro Suzuki Tsuguyori Ohana Akihiro Tanaka 《Diamond and Related Materials》2008,17(1):7-12
Si-containing diamond-like carbon (Si-DLC) coatings with a Si content ranging between 0 (DLC) and 10 at.% were deposited by thermal electron excited plasma CVD method, and their characteristics and the tribological properties in water environment were investigated. The results showed that doped Si had little effect on the hardness and Young's modulus of the coatings. Increasing Si content reduced the friction and the wear of the mated ball, although the wear of the coatings increased. The wear of the counter ball occurred mainly in the early stage of rubbing. The Raman and XPS analysis revealed that the tribochemical reaction of Si-DLC coating occurred in water, and SiOx(OH)y gel was formed on the mated ball surface. It is considered that the tribochemical reaction is also responsible for the tribological properties of the Si-DLC coating and the counter ball, and the reaction may be accelerated by increasing the Si content. Failure-resistant capability is strongly governed by the characteristics of the coating, and can be improved by doping Si. There is an optimum Si content for increasing the failure-resistant capability and it was 6.6 at.% in this work. 相似文献
998.
The growth mechanism of a diffusion-preventive layer formed at elevated temperatures (∼1500 K) between the plasma-sprayed
niobium layer and the plasma-sprayed FeCrAlY matrix in a tungsten fibre-reinforced high-temperature superalloy composite (Nb-coated
W fibre/FeCrAlY composite) was studied. The diffusion-preventive layer was identified as α-Al2O3 by scanning electron microscopy/electron probe microanalysis, energy dispersive X-ray spectrometry analysis, and X-ray diffraction.
Heat-treatment experiments were implemented systematically and it was found that the Al2O3 layer was also formed at the plasma-sprayed Nb/rolled FeCrAl interface. No Al2O3 layer, however, was formed either at the rolled Nb/plasma-sprayed FeCrAlY interface or at the rolled Nb/rolled FeCrAl interface.
In these cases, an intermetallic compound layer was formed instead. A growth mechanism is proposed in which the Al2O3 is attributed to a chemical reaction between the residual oxygen in the plasma-sprayed niobium and aluminium in FeCrAlY or
FeCrAl. The magnitude of the driving force was evaluated by a new model based on thermodyanamics. Numerical calculations have
shown that the proposed growth mechanism is thermodynamically reasonable. 相似文献
999.
1000.
An imaging array consisting of five Yagi-Uda antennas in a dielectric has been constructed for 50 GHz that has antenna patterns suitable for millimetre-wave applications. Crosstalk levels of less than -30 dB between adjacent antennas in an f/1.0 imaging array have been measured in 5 GHz model experiments.<> 相似文献