A 150 MHz 0.6 μm BiCMOS superscalar microprocessor

An implementation of the Pentium microprocessor architecture in 0.6 μm BiCMOS technology is described. Power dissipation is reduced and performance is enhanced over the previous generation. Processor features, implementation technology, and circuit techniques are discussed. An internal clock rate of 150 MHz is achieved at 3.7 V and -55°C     

The effects of impact ionization on the operation of neighboringdevices and circuits

This paper examines the detrimental effects of excess majority carriers and photons induced by impact ionization on the operation of neighboring pn junctions, bipolar transistors, MOS transistors, and circuits. The experimental results show that in addition to an increase in the substrate surface potential due to the excess majority carriers, photons can lower the barrier of a pn junction and, as a consequence, shift the Gummel plot of an npn bipolar transistor. As for the neighboring circuits, an example in which the speed of an NMOS ring oscillator is retarded by impact ionization in a neighboring NMOS transistor is presented     

Parasitic bipolar gain in fully depleted n-channel SOI MOSFET's

Fully depleted SOI MOSFET's include an inherent parasitic lateral bipolar structure with a floating base. We present here the first complete physically based explanation of the bipolar gain mechanism, and its dependence on bias and technological parameters. A simple, one-dimensional physical model, with no fitting parameters, is constructed, and is shown to agree well with simulations and measurements performed on a new type of SOI MOSFET structure. It is shown that parameters which affect the gain, such as SOI layer thickness, body doping concentration and gate and drain voltages, do so primarily by affecting the concentration of holes in the body region. Thus, current gain falls dramatically with increasing drain voltage due to the associated impact ionization driven increase in the hole concentration. Gummel plots of this parasitic bipolar indicate an apparent ideality factor of 0.5 for the hole current, due to the body hole concentration's dependence on drain voltage     

Effect of the polymer matrices on the dielectric behavior of a percolative high-k polymer composite for embedded capacitor applications

High dielectric constant (high-k) polymer composites are of great interest for embedded capacitor applications. Previously, we demonstrated that epoxy—aluminum composites are promising for embedded capacitor applications, because they have a high dielectric constant and a low dielectric loss due to the core—shell structure of the self-passivated aluminum particles. In this work, to further understand the dielectric behavior of aluminum composites, lower-loss polymers such as silicone, polyimide, polynorbornene, and benzocyclobutene were explored as matrices for the aluminum composites. It is found that the polymer matrices can significantly change the dielectric properties of the aluminum composites. A polymer matrix with a lower dielectric constant generally results in a lower dielectric constant of its aluminum composites. In this regard, polymer—aluminum composites have a similar dielectric characteristic as polymer—ceramic composites. Thermomechanical properties of aluminum composites were characterized by a thermomechanical analyzer.     

Fuzzy rule interpolation for multidimensional input spaces in determining d50c of hydrocyclones

Fuzzy rule-based systems have been very popular in many engineering applications. In mineral engineering, fuzzy rules are normally constructed using some fuzzy rule extraction techniques to establish the determination model in predicting the d50c of hydrocyclones. However, when generating fuzzy rules from the available information, it may result in a sparse fuzzy rule base. The use of more than one input variable is also common in hydrocyclone data analysis. This paper examines the application of fuzzy interpolation to resolve the problems using sparse fuzzy rule bases, and to perform analysis of fuzzy interpolation in multidimensional input spaces.     

Adhesion improvement of thermoplastic isotropically conductive adhesive

Generally, isotropically conductive adhesive formulations include epoxy resin as the polymeric matrix. Although epoxy has superior adhesion capability, its drawbacks include the tendency to absorb moisture and lack of reworkability (thermosetting polymer). In this study, a thermoplastic polymer with low moisture absorption (0.28 wt%), called polyarylene ether (PAE2), is used in isotropically conductive adhesive (ICA) formulation. Previous research work by Lu et al. showed that the moisture absorbed into epoxy caused galvanic corrosion, which result in the formation of metal oxide . By using a polymer with low moisture absorption, the amount of water present in ICA will be small, and the corrosion rate and formation of metal oxide can be reduced. However, previous measurements of contact resistance stability of PAE2-based ICA showed that they are not stable on all surface finishes. It was determined that for thermoplastic-based ICA, poor adhesion was the main mechanism for unstable contact resistance. Two methods of adhesion improvement will be evaluated in this work. The first is to use coupling agents and the second is to blend the thermoplastic with epoxy. Both methods showed promise in improving the contact resistance stability of polyarylene ether based ICA.     

A 24-GHz 3.9-dB NF low-noise amplifier using 0.18 /spl mu/m CMOS technology

A 24-GHz low-noise amplifier (LNA) was designed and fabricated in a standard 0.18-/spl mu/m CMOS technology. The LNA chip achieves a peak gain of 13.1 dB at 24 GHz and a minimum noise figure of 3.9 dB at 24.3 GHz. The supply voltage and supply current are 1 V and 14 mA, respectively. To the author's knowledge, this LNA demonstrates the lowest noise figure among the reported LNAs in standard CMOS processes above 20 GHz.     

Polysaccharide‐based artificial extracellular matrix: Preparation and characterization of three‐dimensional,macroporous chitosan,and heparin composite scaffold

Scaffold‐guided tissue engineering based on synthetic and natural occurring polymers has gained many interests in recent year. In this study, the development of a chitosan‐heparin artificial extracellular matrix (AECM) is reported. Three‐dimensional, macroporous composite AECMs composed of heparin (Hep) and chitosan (Chito) were prepared by an interpolyelectrolyte complex/lyophilization method. The Chito‐Hep composite AECMs were, respectively, crosslinked with glutaraldehyde, as well as cocrosslinked with N,N‐(3‐dimethylaminopropyl)‐N′‐ethyl carbodiimide (EDC/NHS) and N‐hydroxysuccinimide (NHS). The crosslinking reactions were examined by FT‐IR analysis. In physiological buffer solution (PBS), the EDC/NHS‐crosslinked Chito‐Hep composite AECM showed a relative lower water retention ratio than its glutaraldehyde‐crosslinked counterparts. The EDC/NHS‐crosslinked Chito‐Hep composite AECMs showed excellent biocompatibility, according to the results of the in vitro cytotoxic test. This result suggested that the EDC/NHS‐crosslinked Chito‐Hep composite AECMs might be a potential biomaterial for scaffold‐guided tissue engineering applications. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

Quadtree based colour quantisation image compression

A new colour quantisation and quadtree based image compression scheme is proposed. The features of the new scheme are that colour palette ordering and requantisation of the decoded image for palette-based monitor displays are not required. Thus, fast decoding and displaying can be achieved     

Interaction of soliton with sinusoidal wave packet

The interaction of a soliton of the Nonlinear Schrodinger Equation (NSE) with a weak sinusoidal wave packet is treated analytically. The second-order soliton solution containing the original soliton and a perturbing soliton is expanded to first order in the amplitude of the perturbating soliton. From this expansion, one obtains the associate function of Gordon (1992) and a continuous change of position and phase of the perturbed soliton. One finds that the soliton experiences a second-order change of velocity under the influence of the perturbation. This result is then used to derive the displacement due to a wave packet of general shape, which is also confirmed by computer simulation