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81.
Yonghee Im Roy K. 《Very Large Scale Integration (VLSI) Systems, IEEE Transactions on》2002,10(3):221-229
Current VLSI design techniques focus on four major goals: higher integration, faster speed, lower power, and shorter time-to-market. These goals have been accomplished mainly by deep submicron (DSM) technology along with voltage scaling. However, scaling down of feature size causes larger interwire capacitance which results in large crosstalk between interconnects. In this paper, we propose a novel predictable circuit architecture, named "optimized overlaying array-based architecture" (O/sup 2/ABA), especially suited for the deep submicron regime. O/sup 2/ABA achieves reduction in crosstalk by considering the current directions and by reducing interwire capacitance. The introduction of "unit cell" leads to regularity, which makes the performance predictable even before layout, and shortens design time. O/sup 2/ABA is compared with other design styles, such as custom design and standard cell approach, in terms of coupling capacitance, area, and delay. 相似文献
82.
Won-Ju Cho Chang-Geun Ahn Kiju Im Jong-Heon Yang Jihun Oh In-Bok Baek Seongjae Lee 《Electron Device Letters, IEEE》2004,25(6):366-368
A plasma-doping technique for fabricating nanoscale silicon-on-insulator (SOI) MOSFETs has been investigated. The source/drain (S/D) extensions of the tri-gate structure SOI n-MOSFETs were formed by using an elevated temperature plasma-doping method. Even though the activation annealing after plasma doping was excluded to minimize the diffusion of dopants, which resulted in a laterally abrupt S/D junction, we obtained a low sheet resistance of 920 /spl Omega///spl square/ by the elevated temperature plasma doping of 527 /spl deg/C. A tri-gate structure silicon-on-insulator n-MOSFET with a gate length of 50 nm was successfully fabricated and revealed suppressed short-channel effects. 相似文献
83.
84.
K. Kim Y. K. Yoon M.-O. Mun S. P. Park S. S. Kim S. Im J. H. Kim 《Journal of Superconductivity》2002,15(6):595-598
We have prepared pentacene films on Si, Al2O3, and glass substrates by thermal evaporation and have investigated their optical properties at room temperature over a wide range of frequencies from infrared to ultraviolet (5 meV to 6.5 eV). A series of optical phonon modes and electronic transitions have been observed. The internal vibrational modes in the infrared region match well their molecular counterparts but the electronic transitions show substantial changes from those of a free pentacene molecule. The HOMO–LUMO gap energy of the pentacene films deposited on Al2O3 and glass substrates is 1.85 eV. 相似文献
85.
A model is presented that describes the wall-to-bed heat transfer in a circulating fluidized bed (CFB) used for the prereduction
of iron ore in the smelting-reduction iron-making process. The model incorporates the core-annulus type flow structure and
the wall emulsion layer growing downward along the surface. Model predictions showed good agreements with measured data taken
from the literature. The hydrodynamic behavior near the wall surface was able to be properly described by the core-annulus
flow structure. A higher heat-transfer coefficient with higher solid circulation flux was obtained in the upper part of the
bed because of the heat input caused by the lateral diffusion of particles from the core. The predicted and measured data
also showed the minima in the heat-transfer coefficients in the lower part of the bed. Model predictions indicated that in
the CFB for the reduction of iron ore particles, it is important to properly control the inlet temperature of the reducing
gas, rather than that of the solid particles. The implications of the behavior of heat transfer in the CFB are discussed for
the reduction of iron oxides. 相似文献
86.
Jyh-Dar Fan L. James Lee Junil Kim Yong-Taek Im 《Polymer Engineering and Science》1989,29(11):740-748
The effects of material flow, heat transfer, part geometry, and curing agents on the cure of sheet molding compounds (SMC) in molds with substructures were analyzed both experimentally and numerically. It was found that heat transfer during mold filling has a profound effect on the cure pattern, especially for fastcure resins molded for parts with thin dimensions. 相似文献
87.
88.
Imène Lahouij Fabrice Dassenoy Ludvig de Knoop Jean-Michel Martin Béatrice Vacher 《Tribology Letters》2011,42(2):133-140
Inorganic fullerene-(IF)-like nanoparticles made of metal dichalcogenides (IF-MoS2, IF-WS2) have been known to be effective as anti-wear and friction modifier additives under boundary lubrication. The lubrication
mechanism of these nanoparticles has been widely investigated in the past and even if the exfoliation and third body transfer
of molecular sheets onto the asperities constitute the prevalent mechanism for the improved tribological behavior of IF nanoparticles,
it has also been suggested that a rolling friction process could also play a role for well crystallized and spherical particles.
In this study, in situ Transmission Electron Microscopy (TEM) observations of the behavior of single IF-MoS2 nanoparticles were conducted using a sample holder that combines TEM and Atomic Force Microscopy (AFM) which simultaneously
can apply normal and shear loads. It was shown that depending on the test conditions, either a rolling process or a sliding
of the fullerenes could be possible. These in situ TEM observations are the first carried out with IF nanoparticles. 相似文献
89.
90.
A PbS-sensitized photovoltaic photodetector responsive to near-infrared (NIR) light was fabricated by depositing monolayered PbS nanoparticles on a mesoporous TiO(2) (mp-TiO(2)) film via the spin-assisted successive ionic layer adsorption and reaction (SILAR) method. By adjusting the size and morphology of the PbS nanoparticles through repeated spin-assisted SILAR cycles, the PbS-sensitized photovoltaic photodetector achieved an external quantum efficiency of 9.3% at 1140 nm wavelength and could process signals up to 1 kHz. 相似文献