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Integrated Circuit (integrated + circuit)

Distribution by Scientific Domains
Engineering45%
Polymers and Materials Science18%
Chemistry18%

Terms modified by Integrated Circuit

  • integrated circuit technology
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    Selected Abstracts

    Amorphous silicon based p-i-i-n photodetectors for point-of-care testing

    PHYSICA STATUS SOLIDI (C) - CURRENT TOPICS IN SOLID STATE PHYSICS, Issue 3-4 2010
    Marc Sämann
    Abstract Modern medical diagnostics demands point-of-care testing (POCT) systems for quick tests in clinical or out-patient environments. This investigation combines the Reflectometric Interference Spectroscopy (RIfS) with thin film technology for a highly sensitive, direct optical and label-free detection of proteins, e.g. inflammation or cardiovascular markers. Amorphous silicon (a-Si) based thin film photodetectors replace the so far needed spectrometer and permit downsizing of the POCT system. Photodetectors with p-i-i-n structure adjust their spectral sensitivity according to the applied read-out voltage. The use of amorphous silicon carbide in the p-type and the first intrinsic layer enhances the sensitivity through very low dark currents of the photodetectors and enables the adjustment of their absorption characteristics. Integrating the thin film photodetectors on the rear side of the RIfS substrate eliminates optical losses and distortions, as compared to the standard RIfS setup. An integrated Application Specific Integrated Circuit (ASIC) chip performs a current-frequency conversion to accurately detect the photocurrent of up to eight parallel photodetector channels. In addition to the optimization of the photo-detectors, this contribution presents first successful direct optical and label-free RIfS measurements of C-reactive protein (CRP) and D-dimer in buffer solution in physiological relevant concentrations. (© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source]

    A Contactless Impedance Probe for Simple and Rapid Determination of the Ratio of Liquids with Different Permittivities in Binary Mixtures

    ELECTROANALYSIS, Issue 1 2009
    Franti, ek Opekar
    Abstract Simple contactless cells with planar or tubular electrodes have been designed for measurement of the permittivity of solutions. The cells, connected to an integrated circuit of astable multivibrator, respond primarily to the capacitance component of the cell impedance, the multivibrator frequency depends in a defined manner on the solution permittivity and is readily used as the analytical signal in determinations of the ratios of components in binary liquid mixtures; water solution of methanol, ethanol and dioxane have been tested. The response of the cell with planar electrodes satisfies well the simple theoretical model and both the cells provide results with a sufficient sensitivity, a low LOD value (units of %vol) and a good precision (around 1%rel). The cell simplicity, small dimensions, long-term stability and the possibility of powering them from a battery make them suitable for hand-held meters. As an example of application in practice, the content of ethanol was determined in the car fuel petrol. [source]

    Growth and Transfer of Monolithic Horizontal ZnO Nanowire Superstructures onto Flexible Substrates

    ADVANCED FUNCTIONAL MATERIALS, Issue 9 2010
    Sheng Xu
    A method of fabricating horizontally aligned ZnO nanowire (NW) arrays with full control over the width and length is demonstrated. A cross-sectional view of the NWs by transmission electron microscopy shows a "mushroom-like" structure. Novel monolithic multisegment superstructures are fabricated by making use of the lateral overgrowth. Ultralong horizontal ZnO NWs of an aspect ratio on the order of ten thousand are also demonstrated. These horizontal NWs are lifted off and transferred onto a flexible polymer substrate, which may have many great applications in horizontal ZnO NW-based nanosensor arrays, light-emitting diodes, optical gratings, integrated circuit interconnects, and high-output-power alternating-current nanogenerators. [source]

    Ventral hippocampal involvement in temporal order, but not recognition, memory for spatial information

    HIPPOCAMPUS, Issue 3 2008
    John G. Howland
    Abstract The hippocampus is critical for spatial memory. Recently, subregional differences in the function of hippocampus have been described in a number of behavioral tasks. The present experiments assessed the effects of reversibly lesioning either the dorsal (dHip) or ventral hippocampus (vHip) on spontaneous tests of spatial recognition and temporal order memory. We report that although the dHip is necessary for spatial recognition memory (RM) (distinguishing a novel from a familiar spatial location), the vHip is involved in temporal order memory (the capacity to distinguish between two spatial locations visited at different points in time), but not RM. These findings and others are consistent with the hypothesis that temporal order memory is supported by an integrated circuit of limbic areas including the vHip and the medial prefrontal cortex. © 2007 Wiley-Liss, Inc. [source]

    Flexible Electronics: Ultrathin Silicon Circuits With Strain-Isolation Layers and Mesh Layouts for High-Performance Electronics on Fabric, Vinyl, Leather, and Paper (Adv. Mater.

    ADVANCED MATERIALS, Issue 36 2009
    36/2009)
    The cover shows a silicon integrated circuit on a paper substrate. The system consists of ultrathin devices electrically and mechanically interconnected with stretchable, serpentine ribbons. A low modulus elastomeric adhesive isolates the circuit from strains associated with bending and folding the paper. This strategy provides a route to high quality electronics on paper, vinyl, leather and other unusual substrates, as reported by John Rogers and co-workers on p. 3703. [source]

    MMICs time-domain electrical physical simulator adapted to the parallel computation

    INTERNATIONAL JOURNAL OF NUMERICAL MODELLING: ELECTRONIC NETWORKS, DEVICES AND FIELDS, Issue 3 2009
    A. El Moussati
    Abstract The programming method used to adapt an existing time-domain electrical circuit simulator to the parallel computation is presented. The originality of the simulator results in the semiconductor device numerical physical modeling. Thus, the organization of the existing software, initially developed to be run on a monoprocessor sequential Unix workstation, is firstly detailed. Accounting for specifications at once regarding the effort necessary to modify the software, the wished simulator application field and the constraints resulting from the available computer, two levels of parallelization have been pointed out and implemented by means of the message passing interface parallel programming tool. As an illustration, some results concerning the simulation of a microwave monolithic integrated circuit (MMIC), especially a 2,40,GHz HEMT transistor cascode stage distributed amplifier, are presented. Circuits of increasing complexity have been considered. The evaluation of the sequential/parallel computation ratio demonstrates that significant gains can be expected from the parallel computation opening the way to analysis of the operation of MMICs of mean complexity by means of a numerical physical approach. Copyright © 2008 John Wiley & Sons, Ltd. [source]

    Enabling a compact model to simulate the RF behavior of MOSFETs in SPICE

    INTERNATIONAL JOURNAL OF RF AND MICROWAVE COMPUTER-AIDED ENGINEERING, Issue 3 2005
    Reydezel Torres-Torres
    Abstract A detailed methodology for implementing a MOSFET model valid to perform RF simulations is described in this article. Since the SPICE-like simulation programs are used as a standard tool for integrated circuit (IC) design, the resulting model is oriented for its application under the SPICE environment. The core of the proposed model is the popular BSIM3v3, but in this model the RF effects are taken into account by means of extrinsic lumped elements. Good agreement between the simulated and measured small-signal S -parameter data is achieved for a 0.18-,m channel-length MOSFET, thus validating the proposed model. © 2005 Wiley Periodicals, Inc. Int J RF and Microwave CAE 15, 2005. [source]

    Design, implementation and verification through a real-time test-bed of a multi-rate CDMA adaptive interference mitigation receiver for satellite communication

    INTERNATIONAL JOURNAL OF SATELLITE COMMUNICATIONS AND NETWORKING, Issue 1 2003
    Luca Fanucci
    Abstract This paper presents the design, the implementation, and the main performance results of a multi-rate code division multiple access (CDMA) interference mitigation receiver for satellite communication. Such activity was performed within a research project supported by the European Space Agency (ESA), whose aim was to demonstrate the suitability of the linear adaptive interference mitigation detector (IMD) named extended complex-valued blind anchored interference-mitigating detector (EC-BAID) for single-user detection of a CDMA signal in third-generation (3G) satellite networks. Such a detector, which exhibits a remarkable robustness to multiple access interference, operates in a blind mode, i.e. it only requires knowledge of the timing of the wanted user's signature code, and is therefore very well suited for integration into handheld user terminals. Experimental results in terms of bit error rate with respect to the theoretical behaviour were derived through a specifically developed test bed. Signal plus multiple access interference generation is performed via a computer-controlled arbitrary waveform generator, followed by frequency up-conversion to the standard intermediate frequency of 70 MHz. Additive white Gaussian noise is then injected with the aid of a precision noise generator. The core of the test bed is a flexible digital receiver prototype featuring the EC-BAID detector plus all functions ancillary to IMD (multi-rate front-end, automatic gain control, code acquisition and tracking, carrier synchronization, etc.). Those functions were implemented through careful mixing of different technologies: field programmable gate arrays (FPGAs) for computing-intensive signal processing functions, digital signal processor (DSP) for housekeeping and monitoring, and application specific integrated circuit (ASIC) for adaptive IMD. The adopted design flow also allows an easy re-use of the prototype architecture to come to an overall integration of the receiver into a single ASIC with modest complexity and power consumption increase with respect to a conventional detector. Copyright © 2003 John Wiley & Sons, Ltd. [source]

    A CMOS opto-electronic single chip using the hybrid scheme for optical receivers

    MICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 9 2008
    Jian-Ming Huang
    Abstract An opto-electronic integrated circuit based on the hybrid scheme for an optical receiver front-end is presented in this article. The proposed integrated circuit adopts the CMOS technology as the vehicle to integrate the InP-based waveguide photodetector into the transimpedance amplifier (TIA) circuit. A regulated cascade structure is used to reduce the input impedance of the TIA. Hence, the proposed integrated circuit can achieve a very high bandwidth provided that the parasitic capacitance of the photodetector is up to 1 pF. The 3-dB bandwidth and the transimpedance gain of the proposed circuit are 1 GHz and 64.5 dB,, respectively. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 2430,2434, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23693 [source]

    A 80,100 GHz image-reject passive-HEMT mixer

    MICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 12 2006
    John W. Archer
    Abstract This paper describes a single-sideband, subharmonically pumped, passive-HEMT integrated circuit mixer developed for use in transceivers for point-to-point telecommunications in the 83,87 GHz band. The gallium arsenide (GaAs) monolithic microwave integrated circuit (MMIC) can readily be fabricated using a standard commercial process. The mixer performs equally well for either up- or down- conversion. For RF signals in the range 80,100 GHz, the conversion loss is typically 20 dB with LO drive in the range 40,50 GHz. Under these conditions, high rejection of the undesired sideband (>18 dB), relative to the desired signal, is achieved. For up-conversion, 1 dB compression of the mixer gain typically occurs at ,12 dBm RF output power. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 2429,2433, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21953 [source]

    Effects of defrosting period on mold adhesion force of epoxy molding compound

    ASIA-PACIFIC JOURNAL OF CHEMICAL ENGINEERING, Issue 2 2009
    Hwe-Zhong Chen
    Abstract In integrated circuit (IC) packaging, when epoxy-molding compound (EMC) is filled in the mold cavity and cured in the mold, adhesion occurs in the interface between EMC and the mold surface. Too large an adhesion force can cause many problems. For example, too large an adhesion force may damage an IC during ejection and cause the package to fail and thus lower the yield rate. To resolve mold adhesion problems, improving the mold design and applying suitable surface treatments, such as mold surface coating, are the common approaches. Applying suitable surface coating is a more popular and practical approach. Defrosting is a process to increase the frozen EMC temperature to room temperature, and to retain it at room temperature for some period before molding. It is a common practice to put EMC under required atmospheric environment during defrosting. It has been found by molding engineers that increased defrosting period will increase the frequency of mold cleaning. But there is no quantitative description on how much the adhesion force increases during the defrosting process. This paper describes the use of a semiautomatic EMC adhesion force test instrument to measure the normal adhesion force between the mold surface and EMC. By measuring the adhesion force, one can quantify how much adhesion force exists between EMC and the mold surface under different defrosting periods. The results show that it is best to use the EMC with 24,32 h of defrosting, to prevent excessive amount of mold adhesion force and it has been found that the adhesion force of the 24 h defrosting period will be 24% less than that of the 48 h defrosting period. Decreasing moisture absorption will decrease the increase in adhesion force for prolonged defrosting period cases. Copyright © 2008 Curtin University of Technology and John Wiley & Sons, Ltd. [source]