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91.
Design and fabrication of single photon avalanche detector (SPAD) in planar technology is reported. Device design and critical issues in the technology are discussed. Experimental test procedures are described for dark-counting rate, afterpulsing probability, photon timing resolution, and quantum detection efficiency. Low-noise detectors are obtained, with dark counting rates down to 10 c/s for devices with 10 /spl mu/m diameter, down to 1 kc/s for 50 /spl mu/m diameter. The technology is suitable for monolithic integration of SPAD detectors and associated circuits.  相似文献   
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In this paper, we present a low power 12 bit 5 MSPS, successive approximation converter architecture using pipeline technique. The converter consumes 4 mW at the Nyquist rate input with 1.8 V power supply. By combination of pipeline and successive architecture, the entire circuit, simulated at the transistor level in a 0.18 μ CMOS process, achieves a FoM (Figure of Merit) of 0.19 pJ/conversion. Jinghua Li was born in 1973. He received the MSEE and BSEE Degree from College of Electronics and information, Shanghai Jiaotong University and Harbin Engineering University in 1997 and 1994 respectively. He is currently pursuing Ph.D degree in Department of Electrical Engineering, Texas A&M University, College Station, TX, USA. In 1997, he joined Bell Laboratory (China), Lucent Technologies as a member of technical staff. He worked on single-chip HDTV decoder IC and Sonet/SDH SoC for various projects in Murray Hill, NJ, USA and Shanghai China. He also finished projects on hardware implementation of Video conference/Phone based on H.263 standard as his master thesis. Since 2000, he has been a research assistant in Analog Mixed Signal center, TAMU. Most currently his research interests are focused on low power analog to digital conversion IC design, CMOS implementation of 10 G/2.5 G clock data recovery IC for high speed serial communications. Franco Maloberti received the Laurea Degree in Physics (Summa cum Laude) from the University of Parma, Parma Italy, in 1968 and the Dr. Honoris Causa degree in electronics from the Instituto Nacional de Astrofisica, Optica y Electronica (Inaoe), Puebla, Mexico in 1996. In 1993 he was a Visiting Professor at ETH-PEL, Zurich. He was Professor of Microelectronics and Head of the Micro Integrated Systems Group University of Pavia, Pavia, Italy and the TI/J.Kilby Analog Engineering Chair Professor at the Texas A&M University. He is currently the Distinguished Microelectronic Chair Professor at University of Texas at Dallas and part-time Professor at the University of Pavia, Italy. His professional expertise is in the design, analysis and characterization of integrated circuits and analogue digital applications, mainly in the areas of switched capacitor circuits, data converters, interfaces for telecommunication and sensor systems, and CAD for analogue and mixed A-D design. He has written more than 250 published papers, three books and holds 15 patents. He was in 1992 recipient of the XII Pedriali Prize for his technical and scientific contributions to national industrial production. He was co-recipient of the 1996 Institute of Electrical Engineers (U.K.) Fleming Premium for the paper “CMOS Triode Transistor Transconductor for high-frequency continuous time filters.” He has been responsible at both technical and management levels for many research programs including ten ESPRIT projects and has served the European Commission as ESPRIT Projects' Evaluator, Reviewer and as European Union expert in many European Initiatives. He served the Academy of Finland on the assessment of electronic research in Academic institutions and on the research programs' evaluations. Dr. Maloberti was Vice-President, Region 8, of the IEEE Circuit and Systems Society from 1995 to 1997 and an Associate Editor of IEEE-Transaction on Circuit and System-II. He received the 1999 IEEE CAS Society Meritorious Service Award, the 2000 CAS Society Golden Jubilee Medal, and the IEEE Millenium Medal. He is the President of the IEEE Sensor Council and member of the Board of Governors of the IEEE CAS Society. He is a member of the Italian Electrothecnical and Electronic Society (AEI), the Editorial Board of Analog Integrated Circuits and Signal Processing, and Fellow of IEEE.  相似文献   
93.
A method of manufacturing polymer-infiltrated ceramics (PICs) is to pre-infiltrate a porous ceramic with a liquid monomer and subsequently polymerize the organic component inside the ceramic structure. The volume reduction during polymerization leads to the formation of pores (defects), which has a detrimental effect on the mechanical properties of PICs. To avoid the generation of defects, a new polymerization method that uses pressure during polymerization was developed. To investigate the influences of pressure and heating rate on strength and microstructure, both parameters were varied. The influences of both parameters on the strength of PICs were studied using a biaxial test. The influence on the microstructure was investigated through microscopy. Fracture toughness and R-curve behavior of the manufactured PICs were determined with the SEVNB method. The process parameters have a strong influence on strength and microstructure of PICs. Defect-free PICs with improved strength could be manufactured using elevated pressure during polymerization. As expected, a distinct R-curve behavior and enhanced fracture toughness relative to composites manufactured using conventional methods was found. The developed manufacturing method leads to defectless PICs with increased mechanic behaviors.  相似文献   
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Radiation damage to fillers such as carbon black, graphite and silica induced by high doses of γ‐radiation or neutrons dramatically increases their ability to adsorb rubber irreversibly. In fact, the ‘bound rubber’, ie the amount of non‐extractable rubber which remains irreversibly linked to the filler matrix, increases dramatically in radiation‐treated fillers. The increased adsorption power of radiation‐damaged fillers has been attributed to the formation of a higher concentration of surface defects in the form of trapped free radicals, fullerene‐like structures and other kinds of defects. The mechanical properties of rubber compounds filled with radiation‐treated carbon blacks show a significant increase in their reinforcing effects, in line with the increased ability to form ‘bound rubber’. © 2001 Society of Chemical Industry  相似文献   
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The milling time evolution of magnetic anisotropy of ball milled powders can be described considering two regimes. First, for short milling times, the main factor affecting the magnetic behavior of the alloy is the accumulation of internal stresses. Second, for long milling times, magnetic anisotropy can be explained using three contributions: long-range magnetoelastic, averaged short-range magnetoelastic and averaged magnetocrystalline anisotropies.  相似文献   
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