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11.
Makon R.E. Lang M. Driad R. Schneider K. Ludwig M. Aidam R. Quay R. Schlechtweg M. Weimann G. 《Electronics letters》2005,41(11):644-646
A 2:1 multiplexer (MUX) and low power selector ICs have been successfully designed and manufactured using an InP/InGaAs DHBT technology. The 2:1 MUX has been tested at data rates up to 80 Gbit/s with an output swing of 600 mV, while the selector IC has achieved operation speed up to 90 Gbit/s at a power consumption of only 385 mW. 相似文献
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Weiner J.S. Lee J.S. Leven A. Baeyens Y. Houtsma V. Georgiou G. Yang Yang Frackoviak J. Tate A. Reyes R. Kopf R.F. Wei-Jer Sung Weimann N.G. Young-Kai Chen 《Solid-State Circuits, IEEE Journal of》2004,39(10):1720-1723
Return-to-zero differential phase-shift keying applications require a differential amplifier with high bandwidth, high gain, low noise, and good input impedance match. In this paper, we describe an InGaAs-InP heterostructure bipolar transistor differential transimpedance amplifier with high bandwidth of 47 GHz and high gain of 56 dB-/spl Omega/. The input-referred current noise is less than 35 pA//spl radic/Hz over the measurement range up to 40 GHz. 相似文献
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R. Quay Dipl.-Phys. Dr. techn. G. Weimann Prof. Dr. rer. nat. 《e & i Elektrotechnik und Informationstechnik》2003,120(3):75-78
An overview of properties and recent achievements for AlGaN/GaN high electron mobility transistors (HEMT) on semi-insulating SiC substrate is given towards high power and broadband applications up to a frequency of 40 GHz. Starting from epitaxial growth and process technology we present state-of-the-art power results obtained at the Fraunhofer Institute (IAF) from AlGaN/GaN HEMTs on SiC. Further, a one-stage 16 GHz MMIC power amplifier circuit with 1.6 W output power is presented. This result represents the first AlGaN/GaN MMIC on SiC fabricated in Europe. 相似文献
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Chertouk M. Heiss H. Xu D. Kraus S. Klein W. Bohm G. Trankle G. Weimann G. 《Electron Device Letters, IEEE》1996,17(6):273-275
We report on fabrication and performance of novel 0.13 μm T-gate metamorphic InAlAs/InGaAs HEMTs on GaAs substrates with composite InGaAs channels, combining the superior transport properties of In0.52Ga0.48As with low-impact ionization in the In0.32Ga0.68As subchannel. These devices exhibit excellent DC characteristics, high drain currents of 750 mA/mm, extrinsic transconductances of 600 mS/mm, combined with still very low output conductance values of 20 mS/mm, and high channel and gate breakdown voltages. The use of a composite InGaAs channels leads to excellent cut-off frequencies: fmax of 350 GHz and an fT 160 GHz at VDS=1.5 V. These are the best microwave frequency results ever reported for any FET on GaAs substrate 相似文献
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L Bastian A Weimann W Bischoff PN Meier M Grotz C Stan G Regel 《Canadian Metallurgical Quarterly》1998,101(2):105-114
A clinical, bacteriological, serological and patho-anatomical study was carried out on 12 goats surviving the acute stage of contagious caprine pleuropneumonia (CCPP), experimentally produced with Mycoplasma capricolum ssp. capripneumoniae (M. capripneumoniae), with the major aims of investigating the chronic stage of the disease and elucidating the possibility of a carrier state beyond the acute fulminant phase. The goats were killed 9, 16, 82 or 126 days after the onset of acute clinical signs. On day 9, clinical signs included low grade fever and persistent coughing. Thereafter, only intermittent coughing was recorded. Serum titres of complement-fixing antibodies to M. capripneumoniae were high at the period of fever but dropped thereafter. Post-mortem examination showed acute fibrinous pleuropneumonia on days 9 and 16, and chronic pleuropneumonia on days 82 and 126, including sequester formations in goats killed on day 126. Mycoplasma capripneumoniae was isolated on days 9 and 16 but not on later occasions. The study showed that goats recovered from acute CCPP may have lesions for a long time thereafter but provide no evidence of a carrier state among long-term survivors. 相似文献