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development of large-area, reverse-type APD-arrays for high-resolution medical imaging

NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT 2009年第1-2期604卷 323-326页

作者： Kataoka, J. Koizumi, M. Tanaka, S. Ishibashi, H. Nakamori, T. Kawai, N. Ikeda, H. Ishikawa, Y. Kawabata, N. Matsunaga, Y. Kishimoto, S. Kubo, H. Tokyo Inst Technol Meguro Ku Tokyo 1528551 Japan Inst Space & Astronaut Sci JAXA Kanagawa 229 Japan Hamamatsu Photon KK Div Solid State Shizuoka Japan Natl Lab High Energy Phys Photon Factory High Energy Accelerator Res Org Tsukuba Ibaraki 305 Japan Kyoto Univ Dept Phys Sakyo Ku Kyoto 606 Japan

Avalanche photodiodes (APD) offer advantages in terms of weak scintillation detection, fast time response, and magnetic field insensitivity. We have developed new types of large-area, reverse-type APD-arrays specifically designed for high-resolution positron emission tomography (PET). Each device has a monolithic 16 x 16 (or 8 x 8) pixel structure with an active area of 1.0 (or 4.0, 0.25) mm(2) for each pixel. An excellent gain uniformity (<= 10%) and low dark noise (<= 0.3 nA) have been achieved, measured at room temperature. Energy resolution of 7.2% (FWHM) was obtained for the direct detection of 5.9 keV X-rays, while 10.2% (FWHM) was obtained for 662 keV gamma-rays when coupled with a LYSO scintillator matrix. An excellent time resolution of 102 ps (FWHM) was obtained for a monolithic, 3 mm phi APD pixel. These results suggest that APD-arrays could be a promising device for future applications in nuclear medicine. (C) 2009 Elsevier B.V. All rights reserved.

关键词： Avalanche photodiode gamma-rays Scintillation detection

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On-Earth Performance Evaluation of SatCom On-The-Move (SOTM) Terminals

On-Earth Performance Evaluation of SatCom On-The-Move (SOTM)...

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IEEE Military Communications conference

作者： Alazab, Mostafa Rieche, Marie Del Galdo, Giovanni Felber, Wolfgang Raschke, Florian Siegert, Gregor Landmann, Markus Ilmenau Univ Technol Inst Informat Technol Helmholtzpl 2 D-98693 Ilmenau Germany Fraunhofer Inst Integrated Circuits IIS D-91058 Erlangen Germany

ISBN: (纸本)9780769551241

applications for SatCom On-The-Move (SOTM) are intended to provide mobile users with communication services such as internet at all the times and places. However, fading due to objects surrounding the earth terminal and antenna depointing due to the vehicle motion represent the main challenges for the development of SOTM systems. Both lead to degradation in the overall Quality of Service (QoS). Moreover, antenna depointing may lead to harmful interference to adjacent satellites. Regulatory authorities define limits for antenna de-pointing and for the Power Spectral Density (PSD) transmitted from the antenna. An integral part of the development of SOTM systems is to demonstrate their overall performance as well as to test the performance of the tracking unit. Such tests and demonstrations are usually performed in field tests where two operational satellites are involved. This contribution proposes an alternative test method which avoids the employment of operational satellites and offers a reliable and repeatable environment for measuring the overall SOTM system performance. Antenna pointing errors can be estimated with higher accuracy along azimuth and additionally along elevation. The proposed method employs a cross shaped sensor array for antenna de-pointing estimation. We therefore name it the 'sensor-Array' method. This contribution compares the performance of this method w.r.t. the state-of-theart, confirming its advantages.

关键词： ANTENNA antennae Satellite communication Quality of service Earth terminals Test Method satellites harmful interference Communication Research EMPLOYMENT Power spectral density Performance Evaluation sensor arrays azimuth antenna pointing

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development of III-N UVAPDs for Ultraviolet sensor applications

Development of III-N UVAPDs for Ultraviolet Sensor Applicati...

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conference on Infrared sensors, Devices, and applications III

作者： Sood, Ashok K. Richwine, Robert A. Welser, Roger E. Puri, Yash R. Dupuis, Russell D. Ji, Mi-Hee Kim, Jeomoh Detchprohm, Theeradetch Dhar, Nibir K. Peters, Roy L. Magnolia Opt Technol Inc 52-B Cummings Pk Woburn MA 01801 USA Georgia Inst Technol Sch Elect Engn Atlanta GA 30332 USA DARPA MTO Arlington VA 22203 USA US Dept Interior AQD Sierra Vista AZ 85636 USA

ISBN: (纸本)9780819497185

High-resolution imaging in ultraviolet (UV) bands has many applications in defense and commercial systems. The shortest wavelength is desired for increased spatial resolution, which allows for small pixels and large formats. In past work, UV avalanche photodiodes (APDs) have been reported as discrete devices demonstrating gain. The next frontier is to develop UVAPD arrays with high gain to demonstrate high-resolution imaging. We will discuss a model that can predict sensor performance in the UV band using APDs with various gain and other parameters for a desired UV band of interest. Signal-to-noise ratios (SNRs) can be modeled from illuminated targets at various distances with high resolution under standard atmospheric conditions in the UV band and the solar-blind region using detector arrays with unity gain and with high-gain APDs. We will present recent data on the GaN-based APDs for their gain, detector response, dark current noise, and 1/f noise. We will discuss various approaches and device designs that are being evaluated for developing APDs in wide-bandgap semiconductors. The paper will also discuss the state of the art in UVAPDs and the future directions for small unit cell size and gain in the APDs.

关键词： Ultraviolet radiation Avalanche photodetectors Signal to noise ratio Pulsed laser operation Atmospheric modeling Ultraviolet detectors sensors Gallium nitride Metalorganic chemical vapor deposition Target detection

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development of a creatinine-sensitive sensor for medical analysis

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sensorS AND ACTUATORS B-CHEMICAL 2004年第1-2期103卷 260-264页

作者： Sant, W Pourciel-Gouzy, ML Launay, J Do Conto, T Colin, R Martinez, A Temple-Boyer, P CNRS LAAS F-31077 Toulouse 4 France HEMODIA SA F-31676 Labege France

Low-cost, disposable, SiO2/Si3N4 chemical field effect transistor (ChemFET) microsensors have been fabricated for pH measurements and adapted to biochemical applications by using polyvinyl alcohol (PVA) enzymatic layers deposited and patterned either by dip-coating, or spin-coating and photolithographic techniques. Both processes have been compared for the development and optimization of a creatinine-sensitive enzymatic field effect transistor (Creatinine-EnFET). Creatinine detection properties have been characterized in dialysate, demonstrating better properties for the spin-coated PVA enzymatic layers. Thus, creatinine sensitivity has been estimated at approximately 30 mV/pCreatinine on the [10-1000 mumol L-1] concentration range. The microsensor will be used for blood analysis and more precisely for haemodialysis. (C) 2004 Elsevier B.V. All rights reserved.

关键词： EnFET pH sensor creatinine detection medical analysis

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Fabrication and properties of ultrasmall Si wire arrays with circuits by vapor-liquid-solid growth

Fabrication and properties of ultrasmall Si wire arrays with...

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Transducers 2001 conference/Eurosensor XVth conference

作者： Kawano, T Kato, Y Futagawa, M Takao, H Sawada, K Ishida, M Toyohashi Univ Technol Dept Elect & Elect Engn Toyohashi Aichi 4418580 Japan

A micro-Si wire probe array chip with on-chip circuits has been developed for the applications on multichannel electrodes of neuroelectronic interface systems. Selective Au-Si2H6 vapor-liquid-solid (VLS) growth method provides a successful Si probe array on Si(1 1 1) wafers in predetermined positions and probe sizes. Si probes with 160 mum in length and 3.5 mum in diameter at tip were grown for 2 h at 700 degreesC. Moreover, the circular cone type shape of the Si probes was controlled by changing the Si2H6 gas pressures in the VLS growth. After wiring process for on-chip circuits on Si(1 1 1) wafers, the Si probes were grown perpendicular to the wafer surface by the VLS growth process. Conductivity of Si probes was controlled by using phosphorous diffusion, resulting in a resistivity of 10(-2) Omega . cm from 10(4) Omega . cm at a diffusion temperature of 1100 degreesC. In in vivo studies, penetrating micro-probe array with low impedance such as the VLS grown Si probes has been desired. Using the VLS grown Si probes, these electrical signals was detected successfully. (C) 2002 Elsevier Science B.V All rights reserved.

关键词： smart neural activity recording sensor penetrating type electrode array vapor-liquid-solid growth micro-Si probe array chip neural interface

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Calibration methods and results for the advanced solid-state array spectroradiometer (ASAS)

Calibration methods and results for the advanced solid-state...

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conference on Multispectral Imaging for Terrestrial applications

作者： Dabney, PW Tierney, MR Irons, JR Kovalick, WM Bur, MC Russell, CA NASA Goddard Space Flight Ctr. (United States) Hughes STX (United States) Univ. of Maryland/College Park (United States)

ISBN: (纸本)0819422061

Improved methods for calibrating and characterizing the CCD array based off-nadir tiltable Advanced solid-state Array Spectroradiometer (ASAS) were developed and applied. sensor characteristics such as radiometric sensitivity, polarization sensitivity, signal-to-noise-ratio, temperature sensitivity, spectral bandpass, spectral distortion, and spatial resolution were measured. Radiometric sensitivity, array temperature sensitivity, and signal-to-noise were measured using a Barium Sulfate coated integrating hemisphere whose output calibration is traceable to NIST. Polarization sensitivity was measured for 62 spectral bands across all 512 spatial pixels (31 K pixels). Spectral bandpass and spectral distortion were measured using a 0.5 meter doublepass monochromator. Spatial resolution (given as the modulation-transfer-function - MTF) and distortion were measured using a combination of monochromatic collimated light to directly measure the point-spread-function (PSF) and the edge spread function (ESF) derived from actual image data. The MTF obtain using the two techniques are compared. Potential improvements to the test setups and methods are described.

关键词： Calibration Polarization Signal to noise ratio sensors Point spread functions Modulation transfer functions Lithium Spectral calibration Monochromators Algorithm development

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Dual mode acoustic wave biosensors microarrays

Dual mode acoustic wave biosensors microarrays

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conference on Bioengineered and Bioinspired Systems

作者： Auner, G Shreve, G Ying, H Newaz, G Hughes, C Xu, JZ Wayne State Univ Dept Elect & Comp Engn Detroit MI 48202 USA

ISBN: (纸本)0819449792

We have developed a highly sensitive and selective acoustic wave biosensor array with signal analysis systems to provide a fingerprint for the real-time identification and quantification of a wide array of bacterial pathogens and environmental health hazards. The device is an unique highly sensitive dual mode acoustic wave platform prototype that, when combined with phage based selective detection elements, form a durable bacteria sensor. arrays of these real-time biosensors are integrated to form a biosensor array on a chip. This research involves advanced piezoelectric aluminum nitride wide bandgap semiconductors, novel micromachining processes, advanced device structures, selective phage displays development and immobilization techniques, and system integration and signal analysis technology to develop the biosensor arrays. The dual sensor platform can be programmed to sense in a gas, vapor or liquid environment by switching between acoustic wave resonate modes. The system may be used in a number of applications including hospital settings for the reduction of nosocomial infections, maintenance of sterile environments in surgical suites, and monitoring for airborn pathogen transmission in public. The ability to use the same sensor in the liquid sensing mode is important for tracing the source of airborn pathogens to local liquid sources.

关键词： biosensor surface acoustic wave surface transverse wave pathogen detection water systems airborn

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Type-II superlattices - a promising material for space applications

Type-II superlattices - a promising material for space appli...

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International conference on Space Optics (ICSO)

作者： Daumer, V. Rutz, F. Woerl, A. Niemasz, J. Mueller, R. Stadelmann, T. Rehm, R. Fraunhofer Inst Appl Solid State Phys IAF Tullastr 72 D-79108 Freiburg Germany

ISBN: (纸本)9781510630772

Type-II superlattices (T2SLs) are currently recognized as the sole material system offering comparable performance to HgCdTe, yet providing higher operability, stability over time, spatial uniformity, scalability to larger formats, producibility and affordability. Hence, T2SL technology is very promising for space applications. Fraunhofer IAF played a vital role in the development of III-As/Sb T2SLs right from the beginning. Mono- and bi-spectral focal plane arrays up to 640x512 pixels for the mid- and long-wavelength infrared (IR) have been demonstrated. The growth of T2SL is performed by molecular beam epitaxy (MBE) in multi-wafer reactors. We report on the excellent homogeneity and reproducibility of the growth process, established in the past years at Fraunhofer IAF. After processing this material to detector arrays, the T2SL detectors have been characterized down to low temperatures (below 40K) with promising properties regarding the dark current. For MWIR and LWIR detectors the resolution limit of the measurement setup with a dark current density of 2x10(-10) A/cm(2) has been reached at 77 K and 36 K, respectively.

关键词： MWIR LWIR InAs/GaSb type-II superlattice T2SL molecular beam epitaxy MBE

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development of SPDT-structured RF MEMS switch

Development of SPDT-structured RF MEMS switch

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TRANSDUCERS 2009 - 15th International conference on solid-state sensors, Actuators and Microsystems

作者： Uno, Yutaka Narise, K. Masuda, T. Inoue, K. Adachi, Y. Hosoya, K. Seki, T. Sato, F. OMRON Corporation MEMS Development Sec. 686-1 Ichimiyake Yasu-City Shiga Japan OMRON Corporation Core Technology Center 9-1 Kizugawadai Kizugawa-City Kyoto Japan

ISBN: (纸本)9781424441938

Here, we propose a practical single pole double throw (SPDT)-structured radio frequency microelectromechanical system (RF MEMS) switch for RF applications. This SPDT switch has a very low insertion loss of 1.0dB and a high isolation of 40dB, up to 10GHz. The fabricated switch is compact in size (5.2x3.0x1.8 mm3) with a Land Grid Array Package. The research and development of an RF MEMS switch has been ongoing in our laboratory for years, and we have achieved practical reliability by using a low vibration actuator against a natural frequency. We describe the correlation between contact reliability and the low vibration actuator, as well as the high frequency performance of our new SPDT switch. ©2009 IEEE.

关键词： Natural frequencies

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Study ofindicators for the development of fluorescence based optical fiber temperature sensors

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sensorS AND ACTUATORS B-CHEMICAL 2006年第1-2期118卷 425-432页

作者： Garcia Moreda, Francisco J. Arregui, Francisco J. Achaerandio, Miguel Matias, Ignacio R. Univ Publ Navarra Dept Ingn Elect & Elect Pamplona Spain

An experimental study about fluorophores, which have never been used before in thermometric applications has been carried out for the development of fluorescence based temperature sensors. Fluorescent dyes like: 10-(3-sulfopropyl) acridinium betaine, quinacrine dihydrochloride, naphthofluorescein, fluorescein and 8-hydroxypyrene-1,3,6-trisulfonic acid trisodium salt have been immobilized on sol-gel derived coatings deposited on optical fibers by dip coating. Comparison between the characteristics of the different sensors revealed that the fluorescent dye 10(3-sulfopropyl) acridinium betaine showed the best performances: a sensitivity around 1 degrees C, response time lower than 8 s in thermal transitions between 30 and 250 degrees C and negligible hysteresis along the dynamic range: 30-250 degrees C (220 degrees C). Extended study of cross-sensitivity and fluorescence degradation when sensors are exposed to volatile organic compounds or humidity variations has been performed with 10-(3-sulfopropyl) acridinium betaine. Consequently, methods for isolating the sensors to the effect of harmful atmospheres have also been developed. (c) 2006 Elsevier B.V. All rights reserved.

关键词： fluorescence optical fiber temperature sensor dip coating sol-gel 10-(3-sulfopropyl) acridinium betaine

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