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Chip Size (chip + size)
Selected AbstractsSequencing of real-world samples using a microfabricated hybrid device having unconstrained straight separation channelsELECTROPHORESIS, Issue 21 2003Shaorong Liu Abstract We describe a microfabricated hybrid device that consists of a microfabricated chip containing multiple twin-T injectors attached to an array of capillaries that serve as the separation channels. A new fabrication process was employed to create two differently sized round channels in a chip. Twin-T injectors were formed by the smaller round channels that match the bore of the separation capillaries and separation capillaries were incorporated to the injectors through the larger round channels that match the outer diameter of the capillaries. This allows for a minimum dead volume and provides a robust chip/capillary interface. This hybrid design takes full advantage, such as sample stacking and purification and uniform signal intensity profile, of the unique chip injection scheme for DNA sequencing while employing long straight capillaries for the separations. In essence, the separation channel length is optimized for both speed and resolution since it is unconstrained by chip size. To demonstrate the reliability and practicality of this hybrid device, we sequenced over 1000 real-world samples from Human Chromosome 5 and Ciona intestinalis, prepared at Joint Genome Institute. We achieved average Phred20 read of 675 bases in about 70 min with a success rate of 91%. For the similar type of samples on MegaBACE 1000, the average Phred20 read is about 550,600 bases in 120 min separation time with a success rate of about 80,90%. [source] DC and small-signal comparison of horizontal emitter designs of InGaP/GaAs heterojunction bipolar transistorsINTERNATIONAL JOURNAL OF NUMERICAL MODELLING: ELECTRONIC NETWORKS, DEVICES AND FIELDS, Issue 6 2009Juan M. López-González Abstract This paper describes the DC and small-signal performance of two InGaP/GaAs heterojunction bipolar transistors (HBTs) that have the same chip size. This is done in order to compare emitter,base designs using the TCAD ATLAS device simulator. The HBT devices analyzed have the same cutoff and maximum frequencies but significant differences are observed in other characteristics such as base,emitter turn-on voltage, saturation collector,emitter voltage, forward current gain, maximum transducer gain and maximum stable gain. Copyright © 2009 John Wiley & Sons, Ltd. [source] Complementary predistorter in CMOS differential power amplifierMICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 4 2010Inn-Yeah Oh Abstract For adaptive improvement of linearity above a 12 dB PAPR for 64QAM WiMAX, a complementary feedback loop in a differential amplifier is adopted as a pre-distorter that is realized using an NMOS cell operating in the triode region in order to compensate the gm3, the third order transconductance, of the differential amplifier. The power amplifier has been implemented in 0.18 ,m CMOS technology, and the chip size is 870 ,m × 1050 ,m. The proposed PA obtains the 42% efficiency at P1dB while improving the IMD by more than 10 dB above 15 dBm output power levels. It shows a gain of as much as 14.5 dB, and a return loss below ,12 dB for 2.3,2.4 GHz operation. Finally, the fabricated PA complies with the spurious emission of WiMAX standards up to 22 dBm. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52:833,836, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25062 [source] Implementation of high quality-factor on-chip tuned microwave resonators at 7 GHzMICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 2 2009Rohat Melik Abstract We report on the design, analytical modeling, numerical simulation, fabrication, and experimental characterization of chip-scale microwave resonators that exhibit high quality-factors (Q-factors) in the microwave frequency range. We demonstrate high Q-factors by tuning these microwave resonators with the film capacitance of their LC tank circuits rather than the conventional approach of using external capacitors for tuning. Our chip-scale resonator design further minimizes energy losses and reduces the effect of skin depth leading to high Q-factors even for significantly reduced device areas. Using our new design methodology, we observe that despite the higher resonance frequency and smaller chip size, the Q-factor is improved compared with the previous literature using traditional approaches. For our 540 ,m × 540 ,m resonator chip, we theoretically compute a Q-factor of 52.40 at the calculated resonance frequency of 6.70 GHz and experimentally demonstrate a Q-factor of 47.10 at the measured resonance frequency of 6.97 GHz. We thus achieve optimal design for microwave resonators with the highest Q-factor in the smallest space for operation at 6.97 GHz. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 497,501, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24103 [source] MMIC medium-power amplifier in K band with matching and power-divider/combiner networks implemented with the use of lumped elementsMICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 6 2002L. Álvarez Abstract The design and measurements of a monolithic K-band medium-power amplifier are reported. The matching, biasing, and power-splitter networks have been implemented with the use of lumped elements, reducing the chip size. The model predictions of passive circuitry have been tested through electromagnetic simulations. The amplifier has shown interesting performance in K band. © 2002 Wiley Periodicals, Inc. Microwave Opt Technol Lett 33: 397,400, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.10334 [source] Design, process, and performance of all-epitaxial normally-off SiC JFETsPHYSICA STATUS SOLIDI (A) APPLICATIONS AND MATERIALS SCIENCE, Issue 10 2009Rajesh K. Malhan Abstract This paper reviews the normally-off (N - off) and normally-on (N - on) SiC junction field effect transistor (JFET) concepts and presents an innovative all-epitaxial double-gate trench JFET (DGTJFET) structure. The DGTJFET design combines the advantages of lateral and buried gate JFET concepts. The lateral JFET advantage is the epitaxial definition of the channel width and the buried gate JFET advantage is the small cell size. In the DGTJFET process the epitaxial embedded growth in trenches facilitates the small cell pitch and the vertical direction of the channel. A detailed numerical simulation analysis compares the potential of the DGTJFET design with reported lateral channel and buried gate JFET structures. Migration enhanced embedded epitaxy (ME3) and planarization processes were developed to realize narrow cell pitch DGTJFETs for high-density power integration. The highly doped vertical channel of the DGTJFET defined by the ME3 growth process makes it possible to accurately control the sub-micron channel dimensions in order to realize a low specific on-state resistance (RON) and a high saturation current capability. The anisotropic nature of SiC is taken into account for the channel design considerations. The successful application of the new process technologies for the development of the all-epitaxial DGTJFETs is discussed. Fabricated 5.5 ,m cell pitch 4H-SiC DGTJFETs demonstrate the saturation current density capability of more than 1000 A/cm2. N - off and N - on DGTJFETs with 2.25 mm squared chip size and 9.5 ,m cell pitch output 15 A and 20 A at gate voltage of 2.5 V and drain voltage of 5.0 V. The specific RON of the N - off and N - on DGTJFETs is at room temperature 8.1 m , cm2 and 6.3 m, cm2, respectively, indicating that N - off devices can be realized at the expense of a slight increase in specific RON of approximately 25%. DGTJFETs with a 13 ,m drift layer doped to 5.0 × 1015 cm,3 are demonstrated with a breakdown voltage in the range of 1200 V to 1550 V at the wafer level with a leakage current below 10 ,A. (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Performance of high-power III-nitride light emitting diodesPHYSICA STATUS SOLIDI (A) APPLICATIONS AND MATERIALS SCIENCE, Issue 5 2008G. Chen Abstract The performance of III-nitride based high-power light emitting diodes (LEDs) is reviewed. Direct color high-power LEDs with 1 × 1 mm2 chip size in commercial LUXEON® Rebel packages are shown to exhibit external quantum efficiencies at a drive current of 350 mA ranging from ,60% at a peak wavelength of ,420 nm to ,27% at ,525 nm. The short wavelength blue LED emits ,615 mW at 350 mA and >2 W at 1.5 A. The green LED emits ,110 lm at 350 mA and ,270 lm at 1.5 A. Phosphor-conversion white LEDs (1 × 1 mm2 chip size) are demonstrated that emit ,126 lm of white light when driven at 350 mA and 381 lm when driven at 1.5 A (Correlated Color Temperature, CCT , 4700 K). In a similar LED that employs a double heterostructure (DH) insign instead of a multi-quantum well (MQW) active region, the luminous flux increases to 435 lm (CCT , 5000 K) at 1.5 A drive current. Also discussed are experimental techniques that enable the separation of internal quantum efficiency and extraction efficiency. One technique derives the internal quantum efficiency from temperature and excitation-dependent photoluminescence measurements. A second technique relies on variable-temperature electroluminescence measurements and enables the estimation of the extraction efficiency. Both techniques are shown to yield consistent results and indicate that the internal quantum efficiency of short wavelength blue (, , 420 nm) high-power LEDs is as high as 71% even at a drive current of 350 mA. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Vertical-type InGaN/GaN light emitting diodes with high efficiency reflector ITO/APC alloy on p-GaNPHYSICA STATUS SOLIDI (C) - CURRENT TOPICS IN SOLID STATE PHYSICS, Issue 7-8 2010Sung Min Hwang Abstract We demostrate the efficient p-type reflector for high performance vertical InGaN/GaN light emitting diodes (LEDs) with 1 × 1mm2 chip size. The reflector consists of Indium-Tin-Oxide (ITO) and Ag-Pd-Cu (APC) alloy. The ITO was inserted between p-GaN layer and APC alloy using RF magnetron sputtering to prevent inter-diffusion of APC into GaN layer. Transmission electron microscopy (TEM) result shows that ITO plays an impotant role as a diffusion barrier to APC alloy. In addition, the contact resistivity of ITO to p-GaN layer was measured to be 1.32 × 10 -3 ,cm2 at annealing temperature of 600 °C for 1 minute. APC alloy was adpoted to acheive a higher reflectance for improvement of a light extraction efficiency. The APC alloy reflector appeared to have a higher reflectivity compared to conventional Ni/Ag film reflector. The verical LEDs with ITO/APC alloy reflectors showed the light-output power of 295 mW at an injection current of 350 mA, which is 15% higher than that with Ni/Ag reflectors. The output power enhancement is attributed to the increase of light extraction efficiency due to high reflectivity of APC alloy (© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] | |||||||||||||