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41.
42.
Xiaoqing Wen Kohei Miyase Tatsuya Suzuki Seiji Kajihara Laung-Terng Wang Kewal K. Saluja Kozo Kinoshita 《Journal of Electronic Testing》2008,24(4):379-391
At-speed scan testing, based on ATPG and ATE, is indispensable to guarantee timing-related test quality in the DSM era. However,
at-speed scan testing may incur yield loss due to excessive IR-drop caused by high test (shift & capture) switching activity.
This paper discusses the mechanism of circuit malfunction due to IR-drop, and summarizes general approaches to reducing switching
activity, by which highlights the problem of current solutions, i.e. only reducing switching activity for one capture while
the widely used at-speed scan testing based on the launch-off-capture scheme uses two captures. This paper then proposes a
novel X-filling method, called double-capture (DC) X-filling, for generating test vectors with low and balanced capture switching activity for two captures. Applicable to dynamic & static
compaction in any ATPG system, DC X-filling can reduce IR-drop, and thus yield loss, without any circuit/clock modification, timing/circuit overhead, fault coverage
loss, and additional design effort.
相似文献
Xiaoqing WenEmail: |
43.
Chihiro J. Uchibori Y. Ohtani T. Oku Naoki Ono Masanori Murakami 《Journal of Electronic Materials》1997,26(4):410-414
Significant reduction of the contact resistance of In0.7Ga0.3As/Ni/W contacts (which were previously developed by sputtering in our laboratory) was achieved by depositing a W2N barrier layer between the Ni layer and W layer. The In0.7Ga0.3 As/Ni/W2N/W contact prepared by the radio-frequency sputtering technique showed the lowest contact resistance of 0.2 Ωmm after annealing
at 550°C for 10 s. This contact also provided a smooth surface, good reproducibility, and excellent thermal stability at 400°C.
The polycrystalline W2N layer was found to suppress the In diffusion to the contact surface, leading to improvement of the surface morphology and
an increase in the total area of the InxGa−As between metal and the GaAs substrate. These improvements are believed to reduce the contact resistance. 相似文献
44.
Makoto Murakami Ken-ichi Suzuki Hideki Maeda Tetsuo Takahashi Akira Naka Norio Ohkawa Mamoru Aiki 《Optical Fiber Technology》1997,3(4):320-338
Optical amplifier techniques have led to the installation of large-capacity submarine systems and further capacity increases seem likely. This paper reviews the FSA submarine system, which flexibly operates at both 2.5 and 10 Gb/s and offers maximum transmission capacity of 60 Gb/s for commercial use. The system configuration as well as its characteristics and upgradability will be introduced, including measurement results on time-division-multiplexing/wavelength-division-multiplexing (TDM–WDM) transmission at bit rates of 10 and 20 Gb/s using non-return-to-zero or soliton pulses. To further increase transmission capacity, TDM–WDM techniques that permit more than 10 Gb/s signal transmission in each data channel should be developed. Thus, pulse formats, which include non-return-to-zero, return-to-zero, or soliton pulses, and dispersion allocation in transmission fibers are significant issues. We introduce and discuss our recent results from high-speed (10 to 40 Gb/s) TDM–WDM signal transmission experiments with regard to the above aspects. 相似文献
45.
Zihan Ma Xiaofei Lu Sunghyun Park Tatsuya Shinagawa Masashi Okubo Kazuhiro Takanabe Atsuo Yamada 《Advanced functional materials》2023,33(25):2214466
Hydrogen is a promising alternative to fossil fuels that can reduce greenhouse gas emissions. Decoupled water electrolysis system using a reversible proton storage redox mediator, where the oxygen evolution reaction and hydrogen evolution reaction are separated in time and space, is an effective approach to producing hydrogen gas with high purity, high flexibility, and low cost. To realize fast hydrogen production in such a system, a redox mediator capable of releasing protons rapidly is required. Herein, α-MoO3, with an ultrafast proton transfer property that can be explained by a dense hydrogen bond network in the lattice oxygen arrays of HxMoO3, is examined as a high-rate redox mediator for fast hydrogen production in acidic electrolytes. The α-MoO3 redox mediator shows both a large capacity of 204 mAh g−1 and fast hydrogen production at a current rate of 10 A cm−2(≈153 A g−1), outperforming most of the previously reported solid-state redox mediators. 相似文献
46.
Numerical prediction of fraction of eutectic phase in Sn−Ag−Cu soldring using the phase-field method
Machiko Ode Minoru Ueshima Taichi Abe Hideyuki Murakami Hidehiro Onodera 《Journal of Electronic Materials》2006,35(11):1969-1974
A combination of macroscale solidification simulation and phase-field calculation is employed to predict the volume fraction
of the eutectic phase in Sn-4.0 mass% Ag-XCu solder alloys (X=0.5–1.1 mass%). The solidification simulation incorporates the
cooling rate in the phase-field simulation. We assume the residual liquid solidifies as eutectic phase when the driving force
for the nucleation of Cu6Sn5 amounts to a critical value, which is determined based on the experimental data. Though the calculation results depend on
the experimental data, the obtained fractions are about 40% for 0.5 mass% Cu and more than 90% for 1.1 mass% Cu alloy, which
shows good agreement with the experimental data. 相似文献
47.
Copper (titanium) [Cu(Ti)] films with low titanium (Ti) concentration were found to form thin Ti-rich barrier layers at the
film/substrate interfaces after annealing, which is referred to as self-formation of the barrier layers. This Cu(Ti) alloy
was one of the best candidates for interconnect materials used in next-generation ultra-large-scale integrated (ULSI) devices
that require both very thin barrier layers and low-resistance interconnects. In the present paper, in order to investigate
the influences of annealing ambient on resistivity and microstructure of the Cu alloys, the Cu(7.3at.%Ti) films were prepared
on the SiO2 substrates and annealed at 500°C in ultra-high vacuum (UHV) or argon (Ar) with a small amount of impurity oxygen. After annealing
the film at 500°C in UHV, the resistivity was not reduced below 16 μΩ-cm. Intermetallic compounds of Cu4Ti were observed to form in the films and believed to cause the high resistivity. However, after subsequently annealing in
Ar, these compounds were found to decompose to form surface TiO
x
and interfacial barrier layers, and the resistivity was reduced to 3.0 μΩ-cm. The present experiment suggested that oxygen
reactive to titanium during annealing played an important role for both self-formation of the interfacial barrier layers and
reduction of the interconnect resistivity. 相似文献
48.
Ukita M. Murakami S. Yamagata T. Kuriyama H. Nishimura Y. Anami K. 《Solid-State Circuits, IEEE Journal of》1993,28(11):1114-1118
This paper describes a single-bit-line cross-point cell activation (SCPA) architecture, which has been developed to reduce active power consumption and to avoid increase in the size of high-density SRAM chips, such as 16-Mb SRAM's and beyond. A new PMOS precharging boost circuit, introduced to realize the single-bit-line structure, is also discussed. This circuit is suitable for operation under low-voltage power supply conditions. The SCPA architecture with the new word-line boost circuit is demonstrated with the experimental device, which is fabricated by a 0.4-μm CMOS wafer process technology 相似文献
49.
Kensuke Nishioka Tatsuya Takamoto Takaaki Agui Minoru Kaneiwa Yukiharu Uraoka Takashi Fuyuki 《Solar Energy Materials & Solar Cells》2005,85(3):429-436
Temperature characteristics of the open-circuit voltage (Voc) were investigated in the temperature range from 30°C to 240°C for the InGaP/InGaAs/Ge triple-junction cells. Also, single-junction cells that had the similar structure to the subcells in the triple-junction cells were studied. In the high-temperature range (from 170°C to 240°C), the temperature coefficients of Voc of the InGaP/InGaAs/Ge triple-junction solar cell (dVoc/dT) were different from those in the low-temperature range (from 30°C to 100°C). This is because photo-voltage from the Ge subcell becomes almost 0 V in the high-temperature range. It was found that the open-circuit voltage of a Ge single-junction cell reduced to almost 0 V temperatures over 120°C under 1 sun condition. 相似文献
50.
Andr Sarto Polo Neyde Yukie Murakami Iha 《Solar Energy Materials & Solar Cells》2006,90(13):1936-1944
Blue-violet anthocyanins from Jaboticaba (Myrtus cauliflora Mart) and Calafate (Berberies buxifolia Lam) were employed as TiO2 dye-sensitizers. Solar cells sensitized by Jaboticaba extracts achieved up to Jsc=9.0 mA cm−2, Voc=0.59 V, Pmax=1.9 mW cm−2 and ff=0.54, while for Calafate sensitized cells the values determined were up to Jsc=6.2 mA cm−2, Voc=0.47 V, Pmax=1.1 mW cm−2 and ff=0.36. Other natural dyes were evaluated without significant photocurrent, demonstrating that only selected extracts are capable of converting sunlight in electricity. The results obtained with extracts of Jaboticaba and Calafate show a successful conversion of visible light into electricity by using natural dyes as wide band-gap semiconductor sensitizers in dye-sensitized solar cells. It also represents an environmentally friendly alternative for dye-sensitized solar cells with low cost production and an excellent system for educational purposes. 相似文献