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81.
Nancy L. Michael Choong-Un Kim Qing-Tang Jiang R. A. Augur P. Gillespie 《Journal of Electronic Materials》2002,31(10):1004-1008
This paper reports on two different electromigration-failure mechanisms competing in Cu interconnects. Accelerated electromigration
tests are conducted on identical single-level, 0.25-μm Cu interconnects with SiN or SiCN passivation. The results indicate
that the failure mechanism can vary with the interface condition of the capping layer. The first failure mechanism, seen primarily
in SiN-capped samples, is characterized by extensive interface damage, believed to be a result of failure led by interface
electromigration. In this failure mode, damage initiates at the capping interface but gradually spreads along all interfaces
of the Cu to form an isolated strand. The competing failure mechanism, found in SiCN-capped samples, is characterized by the
formation and growth of a localized void without extensive interface damage. The absence of interface damage, in addition
to the higher activation energy for failure, suggests that the failure occurs at a more localized inhomogeneity than the interface,
such as grain boundaries. While the exact mechanism of how the capping layer suppresses one mechanism and promotes the other
is unknown, this study reveals that the passivation-interface material and condition have a decisive role in determining the
failure mechanism in Cu interconnects. 相似文献
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Contrary to popular predictions of their decentralizing impact, digital communications contribute to new and more complex forms of corporate integration, reinforcing center periphery problems on a global scale. 相似文献
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When a plate bearing a Lamb wave is in contact with a fluid the wave is attenuated. This report presents a relatively simple model for calculating attention. The validity of the approach is established by comparison of calculated results and measurements. 相似文献
89.
A capacitively coupled contactless conductivity detector cell was designed and constructed suitable for standard HPLC 1.6 mm o.d. (1/16') tubing and columns. Bode plots were acquired in order to determine the optimum input frequency for the new detector cell, with three feedback resistors of increasing resistance (1 MOmega, 3.3 MOmega and 4.7 MOmega) alternately fitted to maximize sensitivity. To evaluate the new detector geometry, a 190 mm x 0.381 mm i.d. (1.59 mm o.d.) column packed with Dionex OmniPac 8.5 microm PAX-100 anion exchange resin was used, with an eluent of 0.5 mM sodium benzoate containing 2% methanol, pumped at 20 microL min(-1), with detection taking place 'on-column'. Standard analytical performance criteria were used to compare the test detector with a commercially available TraceDec C(4)D capillary (360 microm o.d.) detector, with the new detector cell matching the performance of the commercial instrument in terms of linearity, sensitivity and reproducibility. In 'on-column' detection mode, the detector cell could be moved during (or between) chromatographic runs along the length of the packed column bed, to shorten the effective length of the column and thus reduce the retention time of strongly retained sample components, whilst maintaining the resolution of weakly retained components. In addition, the detector could also be applied to the evaluation of the stationary phase packing homogeneity by physically scanning the entire length of the micro-bore column with the moveable detector cell. 相似文献
90.
Denis A. Kissounko Joseph M. Deitzel John W. Gillespie 《European Polymer Journal》2008,44(9):2807-2819
The catalytic effect of montmorillonite clay nanoparticles containing organic modifiers such as quaternary phosphonium salts on cure mechanism of cyanate ester resin (RS-9D) was studied by differential scanning calorimetry (DSC) measurements, FT-IR and NMR spectroscopy as well as mass-spectrometry. The results show that the net catalytic effect arises from the presence of moisture associated with nanoclay particles where organic modifiers act as moisture transport agents. Possible mechanisms for cure pathways are discussed. 相似文献