Solid state devices sensors

This book is intended to provide a background and training suitable for application of impedance spectroscopy to a broad range of applications, such as corrosion, biomedical devices, semiconductors and solid-state devices, sensors, batteries, fuel cells, electrochemical capacitors, dielectric measurements, coatings, elec-trochromic materials, analytical chemistry, and imaging. The emphasis is on generally applicable fundamentals rather than on detailed treatment of applications. The reader is referred to other sources for discussion of specific applications of impedance. ... 

A thermistor is a thermally sensitive, semiconductor solid-state device, which can only sense and not monitor (cannot read) the temperature of a sensitive part of equipment where it is located. It can operate precisely and consistently at the preset value. The response time is low and is of the order of 5-10 seconds. Since it is only a temperature sensor, it does not indicate the temperature of the windings or where it is located but only its preset condition. 

A. Mandelis, and C. Christofides, Solid State Gas Sensor Devices, in Chemical Analysis, John Wiley Sons, New York (1993). 

J.F. Schenck, Technical difficulties remaining to the application of ISFET devices, in Theory, Design and Biomedical Applications of Solid State Chemical Sensors (P.W. Cheung, ed.), pp. 165—173. CRC Press, Boca Raton (1978). 

S. Kaneko, Solid-State Image Sensor Masakiyo Matsumura, Charge-Coupled Devices M.A. Bosch, Optical Recording... 

When microelectronics and solid state devices developed over the last five to four decades, the development of solid-state sensors followed suit, resulting in the introduction of NTC and PTC resistors to monitor temperature, and first Reed relais and inductive sensors to determine position and distance, or tachometers for rotational measurements in washing machines and dish washers over the past two decades. 

P. G. LeComber and W. E. Spear, The Development of the a-Si H Field-Effect Transistor and Its Possible Applications D. G. Ast, a-Si H FET-Addressed LCD Panel S. Kaneko, Solid-State Image Sensor M. Matsumura, Charge-Coupled Devices M. A. Bosch, Optical Recording A. D Amico and G. Fortmato, Ambient Sensors H. Kukimoto, Amorphous Light-Emitting Devices R. J. Phelan, Jr., Fast Detectors and Modulators J. I. Pankove, Hybrid Structures... 

Another type of high temperature solid state O2 sensor that has been developed is based on the principle of electrochemical pumping of oxygen with Zr02 electrolytes. These sensors have higher sensitivity (generally, a first power dependence on Pq) than the Nernst cell and the resistive device and possess a number of other characteristics that make them very promising for many new applications. 

In this review the basis for the chemical sensitivity of these devices will be explored and the various device structures used for these sensors will be discussed. A survey of the performance of the diode-type and capacitor-type structures will be presented and a comparison of characteristics of these two classes of solid state gas sensors will be given. 

T. Wagner, T. Yoshinobu, C. Rao, R. Otto andM.J. Schoning, All-in-one solid-state device based on a light-addressable potentiometric sensor platform, Sens. Actuators B Chem., 117(2) (2006) 472—479. 

Ion selective membranes are the active, chemically selective component of many potentiometric ion sensors (7). They have been most successfully used with solution contacts on both sides of the membrane, and have been found to perform less satisfactorily when a solid state contact is made to one face. One approach that has been used to improve the lifetime of solid state devices coated with membranes has been to improve the adhesion of the film on the solid substrate (2-5). However, our results with this approach for plasticized polyvinylchloride (PVC) based membranes suggested it is important to understand the basic phenomena occurring inside these membranes in terms of solvent uptake, ion transport and membrane stress (4,6). We have previously reported on the design of an optical instrument that allows the concentration profiles inside PVC based ion sensitive membranes to be determined (7). In that study it was shown that water uptake occurs in two steps. A more detailed study of water transport has been undertaken since water is believed to play an important role in such membranes, but its exact function is poorly understood, and the quantitative data available on water in PVC membranes is not in good agreement (8-10). One key problem is to develop an understanding of the role of water uptake in polymer swelling and internal stress, since these factors appear to be related to the rapid failure of membranes on solid substrates. 

In the area-image sensor, it is expected that highly sensitive solid-state image sensors with high resolution, competitive with vidicons, will become available. The solid-state image sensor, which is made of an a-Si H photodiode array on a Si IC scanner, is the most suitable device for this purpose. 

Measurement of the previously mentioned parameters has proved to be extremely important in the framework of the many industrial and scientific problems at the instrumentation and control levels. In the context of this work, solid-state device that can sense chemical species or physical quantities and give an electric signal as output will be called sensor. 

The last volume of this miniseries, 21, Part D, covers device applications, including solar cells, electrophotography, image pickup tubes, field effect transistors (FETs) and FET-addressed liquid crystal display panels, solid state image sensors, charge-coupled devices, optical recording, visible light... 

The present availabihty of numerous types of solid electrolytes permits transport control of various kinds of mobile ionic species through those solid electrolytes in solid electrochemical cells, and permits electrochemical reactions to be carried out with the surrounding vapor phase to form products of interest. This interfacing of modem vapor deposition technology and solid state ionic technology has led to the recent development of polarized electrochemical vapor deposition (PEVD). PEVD has been applied to fabricate two types of solid state ionic devices, i.e., solid state potenfiometric sensors and solid oxide fuel cells. Investigations show that PEVD is the most suitable technique to improve the solid electrolyte/electrode contact and subsequently, the performance of these solid state ionic devices. 

The performance of the photomultiplier (representative of a very fast responding sensor even in terms of modern solid state devices) is shown in the lower curves and its performance is in complete contrast to that of the cadmium sulfide cell. The time constant, determined again from the slope of the log curve, was found to be only 40 milliseconds. Such a response time is generally acceptable for most GC and LC separations. Nevertheless in both fast GC and fast LC solutes can be eluted in less than 100 milliseconds in which case an... 

Metal- or metal-oxide-based gas sensors are the most widely used solid-state devices for detecting gases in the environment and atmosphere. The high specific surface areas and uniform mesopores of mesoporous materials will result in a higher probability for a gas to interact with the sensing compounds or sites, which is likely to increase the sensitivity of the material.[310]... 

Yao, S. and Stetter, J.R. (2005) Solid-state NOx sensor based on surface modifications of the solid electrolyte. Proceedings of the Electrochemical Society, 2000-52 Solid-State Ionic Devices II Ceramic Sensors, The Electrochemical Society, Pennington. New Jersey, pp. 252-60. 

Jones T A, Bott B, Hurst N W and Mann B 1983 Solid state gas sensors zinc oxide single crystals and metal phthalocyanine films Proc. Int. Meeting on Chemical Sensors (Analytical Chemistry Symposia Series 17, Fukuoda 1993) ed T Seiyama, K Fueki, J Shiokawa and S Suzuki (New York Elsevier) pp 90-4 Saeki H and Suzuki S 1992 Organic thin film semiconductor device Japanese Patent IPX 19881102 63-277732 US Patent 3 Q19 595 Lewis A 1967 The Palladium Hydrogen System (New York Academic)... 

In different studies, it was recognised that mine detection by EN in the field conditions is limited by the parameters of the sensors. An increase of the sensitivity of the devices seems to be the primary task of most current developments, because veiy small amounts of the characteristic volatile compounds (mostly in ppb or even sub-ppb intervals) have to be traced and recognised in gas mixture. Another limitation for the EN applications is related to comparatively long response time of the sensors when small amounts of the chemicals are to be detected. Low rate of adsorption and desorption process for complex volatile compounds seems the main problem in reduction of the detection time in EN especially when it includes solid-state gas sensors. 

This review is written from the point of view of a chemist who is interested in sensors rather than from that of one whose main interest is the analysis of gases as a discipline in its own right. Therefore although the current literature on solid state gas sensors greatly outnumbers that on membrane type sensors this review concentrates on the latter. The reader interested in solid state devices is referred to a number of excellent reviews and conference proceedings which have appeared recently [5-9]. 

Gas sensors for detecting the atmospheric environment must be able to operate stably under deleterious conditions, including chemical and/or thermal attack. Therefore, solid-state gas sensors would appear to be the most appropriate in terms of their practical robustness. Yamazoe describes a gas sensor as a device that basically performs two functions the receptor and the transducer functions... 

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