检索结果-内蒙古大学图书馆

Influence of atmospheric pollutants on the conductance of phthalocyanine films

sensorS AND ACTUATORS B-CHEMICAL 1999年第1-3期57卷 69-74页

作者： de Haan, A Debliquy, M Decroly, A Fac Polytech Mons B-7000 Mons Belgium

Molecular oxygen has always been considered as the main gaseous agent responsible for the doping of intrinsically insulating phthalocyanine thin films. In this paper, it is shown that oxygen has only a relatively minor effect on electrical conductance and that traces (<100 ppb) of nitrogen dioxide present in ambient atmosphere play a much more important role especially in the presence of water vapour. The effects of chlorine and ozone at the same concentration have also been investigated. (C) 1999 Elsevier Science S.A. All rights reserved.

关键词： gas sensor phthalocyanine nitrogen dioxide ozone chlorine moisture

来源：评论

学校读者我要写书评

暂无评论

Moving gas outlets for the evaluation of fast gas sensors

引用

sensorS AND ACTUATORS B-CHEMICAL 1999年第1-3期58卷 389-393页

作者： Tobias, P Mårtensson, P Göras, A Lundström, I Spetz, AL Linkoping Univ Swedish Sensor Ctr S SENCE S-58183 Linkoping Sweden Linkoping Univ Appl Phys Lab S-58183 Linkoping Sweden MECEL AB S-66200 Amal Sweden

A new method for the evaluation of fast gas sensors is described. By using moving gas outlets, we can quickly change the ambient around a sensor. Different platinum-insulator-silicon carbide (MISiC) structures are investigated. Their sensor response contains fast components, which respond within milliseconds to a change in the ambient from a reducing gas to an oxidising gas and vice versa. Cylinder specific monitoring of car engines with the MISiC structures is discussed. (C) 1999 Elsevier Science S.A. AU rights reserved.

关键词： gas sensors automotive electronics flow silicon carbide high temperature MIS devices

来源：评论

学校读者我要写书评

暂无评论

Influence of catalytic reactivity on the response of metal-oxide-silicon carbide sensor to exhaust gases

引用

sensorS AND ACTUATORS B-CHEMICAL 1999年第1-3期57卷 159-165页

作者： Svenningstorp, H Tobias, P Lundström, I Salomonsson, P Mårtensson, P Ekedahl, LG Spetz, AL Linkoping Univ S SENCE S-58183 Linkoping Sweden Linkoping Univ Div Appl Phys S-58183 Linkoping Sweden AB Volvo Technol Dev S-40508 Gothenburg Sweden

Catalytic metal insulator silicon carbide, MISiC, Schottky diodes are promising devices for on board exhaust diagnosis in cars. These sensors show a direct or indirect sensitivity to gases like H-2, CO, HC (hydrocarbons) and O-2. The catalytic reactivity of the sensor will effect the gas sensing conditions. In some situations knowledge about the reactivity of the catalytic surface may give more information about the exhaust gas composition. For instance, the sensor signal normally moves to a lower voltage in an ambient containing H-2 and HC, however, under certain conditions when exposed to rich gas mixtures, the HC response is opposite the one for H-2. Measurements performed by the MISiC sensors on simulated exhaust gas mixtures, either rich or lean, are shown here. Some fundamental studies of the HC response have been performed. Reaction limitation conditions are suggested as an explanation for the response of HC opposite the one of H-2. (C) 1999 Elsevier Science S.A. All rights reserved.

关键词： HC silicon carbide exhaust Schottky diode field effect device

来源：评论

学校读者我要写书评

暂无评论

High-density and alignment-tolerant integration of monitoring photodetector arrays onto polymeric guided-wave components

引用

IEEE TRANSACTIONS ON ADVANCED PACKAGING 1999年第4期22卷 534-540页

作者： van der Linden, JE De Dobbelaere, PM Van Daele, PP Diemeer, MB European Patent Off NL-2280 HV Rijswijk Netherlands Univ Ghent IMEC INTEC Dept B-9000 Ghent Belgium Opt Micro Machines Inc San Diego CA 92121 USA Akzo Nobel Cent Res RGE Dept NL-6800 SB Arnhem Netherlands

We report on a hybrid integration concept which allows high-density and alignment-tolerant surface mount assembly of top-illuminated photodetector (PD) arrays onto polymeric guided-wave components by means of a micromachined submount with an integrated mirror, This research aims at the development of polymeric waveguide based devices with an embedded optical power monitoring capability for applications in optical fiber communication networks. A prototype integrated multichannel optical power monitor comprising an eight-channel PD module and a polymeric waveguide splitter array was demonstrated which exhibited an average insertion loss of 5.2 dg, a PD coupling efficiency of -2.6 dB, and a crosstalk value of -17.1 dB between adjacent channels, Low polarization and wavelength sensitivity (sigma < 0.1 dB) was confirmed over a spectral range of 40 nm in both telecom wavelength windows.

关键词： hybrid integration network monitoring and management optical fiber communication polymeric waveguide components silicon micromachining

来源：评论

学校读者我要写书评

暂无评论

The semistor: a new concept in selective methane detection

引用

sensorS AND ACTUATORS B-CHEMICAL 1999年第1-3期57卷 108-114页

作者： Williams, G Coles, GSV Univ Coll Swansea Dept Elect & Elect Engn Swansea SA2 8PP W Glam Wales

Technology associated with both catalytic and semiconductor-based gas sensors has been combined to produce hybrid devices capable of detecting low levels of combustible gases. First-generation non-selective sensors, which respond to a wide range of reducing gases including hydrogen, carbon monoxide, lower hydrocarbons and ethanol vapour, were obtained by coating narrow diameter platinum wire coils with a low resistivity tin dioxide-based formulation. As in the case of catalytic sensors, semiconductor-based pelli stors (semistors) art: typically operated in a bridge-type circuit. However, in contrast to catalytic sensors, which rue used to detect percentage levels of combustible gases, semistors are responsive to sub-100 ppm concentrations. Optimisation experiments have been carried out on factors affecting performance, such as sensing layer composition, coil pitch and firing time. A further study on the effects of incorporating an additional catalyst-containing surface filter layer has led to the development of a second-generation methane-selective sensor. Undesirable humidity and ambient temperature effects, normally associated with tin dioxide-based sensors, can be eradicated by operating a semistor in conjunction with a compensating element. This utilises a filter layer, which removes all target gas response while retaining the same humidity and temperature dependence as the sensor. (C) 1999 Elsevier science S.A. All rights reserved.

关键词： gas sensor methane catalytic tin dioxide

来源：评论

学校读者我要写书评

暂无评论

Performance analysis of a Thermionic Thermal Detector at 400K, 300K, and 200K

Performance analysis of a Thermionic Thermal Detector at 400...

引用

Infrared Technology and applications XXV conference

作者： Murguia, JE Tedrow, PK Shepherd, FD Leahy, D Weeks, MM Solid State Sci Corp Hollis NH 03049 USA

ISBN: (纸本)0819431729

The Thermionic Thermal Detector (TTD) senses infrared radiation by temperature modulation of thermionic emission current within a silicon Schottky diode. The thermionic emission current is the well known Richardson dark current. The TTD operates in the LWIR band. The physics of TTD operation is distinct from that of silicon Schottky barrier MWIR detectors, such as PtSi/Si which are based on internal photoemission. In fact, the TTD has high detection efficiency. The architecture of a TTD array is very similar to that of microbolometer arrays, except the detector elements are thermally isolated Schottky diodes, operating under reverse bias. When the TTD array is illuminated by an infrared image, the temperature of individual detector elements will vary with the local incident power of the image. Under small signal conditions, the dark current of individual detectors will vary as temperature, resulting in an electronic image of the infrared scene. The reverse bias dark current of a Schottky diode varies exponentially with temperature. For the small temperature variations observed on the focal plane of an uncooled sensor, this variation is approximately linear. The rate of temperature variation is determined by the Schottky barrier potential and, to a lesser extent by the applied bias potential. The operating temperature range of the detector can be designed into the device by selecting a metal with the appropriate Schottky barrier height. Experimental Schottky barrier heights were determined using Richardson dark current activation energy analysis. Devices optimized for operation at room ambient temperature have a 6%/K temperature coefficient. The use of Schottky diode thermionic emission for uncooled infrared imaging offers several advantages relative to current technology. TTD manufacture is 100% silicon processing compatible. Schottky barrier based thermionic emission arrays have the same uniformity characteristics as MWIR Schottky barrier photoemissive arrays. Oper

关键词： thermal imaging uncooled detection Schottky diode thermionic emission metal-silicide arrays

来源：评论

学校读者我要写书评

暂无评论

Gaining information advantage - An integrated approach to airborne mission recording

Gaining information advantage - An integrated approach to ai...

引用

conference on Cockpit Displays VI - Displays for Defense applications

作者： Sundgren, M Ljunggren, L Swedish Defence Material Administration (Sweden) Ericsson Saab Avionics AB (Sweden)

ISBN: (纸本)0819431648

Information advantage is the key success factor in all conflicts. In a modern combat aircraft the amount of available information is continuously increasing with new and more sophisticated sensor systems. By incorporating an integrated mission recording system the vast amount of information captured in a modern combat aircraft is recorded. Evaluating this information, whether for aircraft development, pilot training or in combat, will maximize the experience from each night and enhance the efficiency of the following missions. All Lot 3 of the Swedish fighter JAS39 Gripen as well as the export versions will be equipped with a digital mission recording system. The system is called DiRECT and is used for video, audio and data recording on a direct access, solid-state memory.

关键词： digital mission recording and data transfer training intelligence peace support continuous technology insertion solid-state recorder EW-data primary radar data reference images image transfer

来源：评论

学校读者我要写书评

暂无评论

Heteroepitaxial growth of 3C-SiC on SOI for sensor applications

Heteroepitaxial growth of 3C-SiC on SOI for sensor applicati...

引用

2nd European conference on Silicon Carbide and Related Materials (ECSCRM 98)

作者： Krötz, G Möller, H Eickhoff, M Zappe, S Ziermann, R Obermeier, E Stoemenos, J Daimler Benz AG Dept FT2M D-81663 Munich Germany Tech Univ Berlin Berlin Germany Aristotelian Univ Salonika GR-54006 Salonika Greece

Typical industrial high temperature sensor applications are reviewed and a short overview of the different high temperature sensor technologies is given. The pros and cons are weighted. Silicon carbide on insulator (SiCOIN) technology comes out to be the most attractive, provided the state of development can be brought up to the one of silicon and silicon on insulator (SOT). Due to the lack of commercially available SIC on SOI wafers, a new SiC on SOI technology has been developed. It is based on the precursor gas methylsilane. The low temperature growth process is described and in-situ n-type doping, which is necessary for sensor applications, has been carried out successfully over a wide range of concentrations without loosing the good crystal properties. Actually the full process is being transferred from a test reactor to a 4 inch machine. This should provide 3C-SiC on SOI wafers for commercial sensor applications. A demonstrator of combustion pressure sensor dedicated to pressure-based engine control is shown. Results of the pressure sensor fitted in a motor-test setup are summarized. (C) 1999 Elsevier Science S.A. All rights reserved.

关键词： Semiconducting silicon compounds

来源：评论

学校读者我要写书评

暂无评论

sensor systems-interface between environment and application

Sensor systems-interface between environment and application

引用

European conference on solid-state Circuits (ESSCIRC)

作者： D. Hammerschmidt Fraunhofer Institute of Microelectronic Circuits and System Duisburg Germany

The rapidly growing market for sensor systems on the one hand boosts the development of new sensor principles and technologies [1,2], on the other hand the increasing fields of use require an integration of these sensors on system level under a wide spread of application conditions. This paper will discuss the main tasks that have to be solved by the electronic system, which interfaces the sensor and the application environment [3,4]. On side of the sensor physical points of view dominate the requirements, which, e.g., call for low noise readout, high gain, minimum sensor loading, and compensation of crossensitivities. The application requires completely different considerations, like compatibility with former solutions, standardized interfaces, low power consumption or networking capability as well as cost efficiency. Between these completely different classes of requirements electronic circuitry operates as a mediator featuring sophisticated readout electronics for each type of sensor, intermediate signal processing layers, and customisable interfaces that are usable for all kinds of sensors. After the general consideration of the above topics some examples of sensor systems will be presented and the individual solutions of the mentioned challenge will be discussed from the circuit designers point of view. At last some approaches for future developments of sensor systems will be presented.

关键词： sensor systems sensor arrays Magnetic sensors sensor systems and applications Chemical sensors Costs Consumer electronics Circuits Pressure measurement Manufacturing

来源：评论

学校读者我要写书评

暂无评论

Low-noise HEB heterodyne receivers and focal plane arrays for the THz regime using NbN

Low-noise HEB heterodyne receivers and focal plane arrays fo...

引用

conference on Terahertz and Gigahertz Photonics

作者： Yngvesson, KS Gerecht, E Musante, CF Zhuang, Y Ji, M Goyette, TM Dickinson, J Waldman, J Yagoubov, PA Gol'tman, GN Voronov, BM Gershenzon, EM Univ Massachusetts Dept Elect & Comp Engn Amherst MA 01003 USA

ISBN: (纸本)0819432814

Low-noise receiver technology for the THz frequency region is presently under development primarily for astronomical observations and remote sensing of the earth's atmosphere from space. With the advent of the upcoming solid-state sources and space-qualified lasers, a much wider spectrum of applications will become available. In the last few years, the new technology of Hot Electron Bolometric (HEB) mixers has demonstrated record low noise temperatures. A reasonable estimate of the potential DSB receiver noise temperature is 10 x hf/2k (where hf/2k is the quantum limited DSB noise temperature) and recent measured results approach this. Furthermore, the LO power requirement of HEB receivers can be satisfied by existing technologies. We have developed prototype HEB receivers using thin film superconducting NbN devices deposited on silicon substrates. The devices are quasi-optically coupled through a silicon lens and a self-complementary log-periodic toothed antenna. We measured DSB receiver noise temperatures of 500 K (13 x hf/2k) at 1.56 THz and 1,100 K (20 x hf/2k) at 2.24 THz. Noise temperatures are expected to fall further as devices and quasi-optical coupling methods are being optimized. The measured 3 dB IF conversion gain bandwidth for one device was 3 GHz, and it is estimated that the bandwidth over which the receiver noise temperature is within 3 dB of its minimum value is 6.5 GHz which is sufficient for a number of practical applications. We will discuss our latest results and give a detailed description of our prototype setup and experiments. We will also discuss our plans for developing focal plane arrays with tens of HEB mixer elements on a single silicon substrate which will make real time imaging systems in the THz region feasible.

关键词： terahertz technology low-noise receivers heterodyne detectors hot electron bolometer superconducting films submillimeter wave astronomy submillimeter wave remote sensing focal plane array terahertz imaging

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：