Experimental validation of crosstalk simulations for on-chip interconnects using S-parameters

Since the design of advanced microprocessors is based on simulation tools, accurate assessments of the amount of crosstalk noise are of paramount importance to avoid logic failures and less-than-optimal designs. With increasing clock frequencies, inductive effects become more important, and the validity of assumptions commonly used in simulation tools and approaches is unclear. We compared accurate experimental S-parameters with results derived from both magneto-quasi-static and full-wave simulation tools for simple crosstalk structures with various capacitive and inductive couplings, in the presence of parallel and orthogonal conductors. Our validation approach made possible the identification of the strengths and weaknesses of both tools as a function of frequency, which provides useful guidance to designers who have to balance the tradeoffs between accuracy and computation expenses for a large variety of cases     

Achieving product variety through optimal choice of module variations

The trade-off in designing products typically involves consideration of manufacturing and development costs, and the potential market share. Modular design of products has been identified as one way of providing firms with a competitive advantage. In the context of modular product design, some of the pertinent questions are: (i) how many product varieties in a product group should be introduced in the market; and (ii) what is the minimum number of module-options required to support this variety? In this paper we study the optimality of such decisions related to modularization in two separate scenarios: (i) the module supplier is an independent operator whose decisions are not coordinated with that of the firm; and (ii) the module supplier is a wholly owned subsidiary of the firm. For these scenarios, we show how the choice of module-options affects product variety, total sales, product development cost, and hence, the firm's profit. We establish that the module-options can be rank ordered, based on profit margin and customer rating, and that the optimal set of module-options to be acquired or developed would include only the top ranked options. We also show how to determine the number and type of module-options a firm should acquire to maximize its profit. Finally, we discuss how our algorithm can be extended to the case of firms that deal with products having multiple module-types.     

Application of photoconductivity decay and photocurrent generation methods for determination of minority carrier lifetime in silicon

Minority carrier lifeline, τ, is one of the most important parameters which has a decisive effect on the performance of silicon devices based on excess carriers. The value of τ is greatly affected by the presence of impurities and defects in silicon and its value provides a fair indication of quality of the material. Photoconductivity decay (PCD) and photocurrent generation (PCG) methods are simple and low cost methods of measurement of minority carrier lifetime in silicon wafers. However, their application requires care. The PCD method can give quite misleading results in case of polycrystalline wafers if there exists potential barriers at the grain boundaries which may affect majority carrier mobility significantly. PCG needs creation of an inducedp ₊-p-n ₊ structure of substantially good quality that should not degrade with time. For PCG method the T measurement under vacuum conditions provides correct and consistent results.     

The simultaneous addition of styrene maleic anhydride copolymer and multiwall carbon nanotubes during melt‐mixing on the morphology of binary blends of polyamide6 and acrylonitrile butadiene styrene copolymer

The effect of simultaneous addition of multiwall carbon nanotubes (MWNTs) and a reactive compatibilizer (styrene maleic anhydride copolymer, SMA) during melt‐mixing on the phase morphology of 80/20 (wt/wt) PA6/ABS blend has been investigated. Morphological analysis through scanning and transmission electron microscopic analysis revealed finer morphology of the blends in presence of SMA + MWNTs. Fourier transform infrared spectroscopic analysis indicated the formation of imide bonds during melt‐mixing. Non‐isothermal crystallization studies exhibited the presence of a majority faction of MWNTs in the PA6 phase of 80/20 (wt/wt) PA6/ABS blend in presence of SMA + MWNTs. Rheological analysis, dynamic mechanical thermal analysis, and thermogravimetric analysis have demonstrated the compatibilization action of simultaneous addition of a reactive compatibilizer (SMA copolymer) and MWNTs in PA6/ABS blends. An attempt has been made to investigate the role of simultaneous addition of SMA copolymer and MWNTs on the morphology of 80/20 (wt/wt) PA6/ABS blend through various characterization techniques. POLYM. ENG. SCI., 55:457–465, 2015. © 2014 Society of Plastics Engineers     

Distribution of mineral species in different coal seams of Talcher coalfield and its transformation behavior at varying temperatures

International Journal of Coal Science & Technology - Mineral phase characterization and thorough understanding of its transformation behavior during combustion are imperative to know the...