Chemically sensitive field effect transistor

Janata, J. Chemically Sensitive Field Effect Transistors, in Solid State Chemical Sensors (Janata, J., Huber, R. J., eds.) New York Academic Press 1985, p. 65... 

Shin JE. 1989. Evaluation of chemically-sensitive field-effect transistors for detection of organophosphorus compounds. Wright-Patterson AFB, OH Air Force Institute of Technology. NTIS No. AD-A215-536. 

G.F. Blackburn, Chemically sensitive field-effect transistors, in Biosensors Fundamentals and Applications (A.P.F. Turner, I. Karube, and G.S. Wilson, eds), pp. 481-530. Oxford University Press, Oxford (1987). 

Chemically modified waxes, 26 220 Chemically resistant fibers, 13 389 Chemically sensitive field-effect transistors (ChemFETs), 22 269. See also Field effect transistors (FETs)... 

J. Janata and R. J. Huber, Chemically sensitive field effect transistors. Chapter 3 of... 

H. E. Katz, Chemically Sensitive Field-efFect Transistors and Chemiresistors New Materials and Device Structures , Electroanalysis 16, 1837 (2004). 

Chemically sensitive field effect transistor - CHEM-FET... 

Electrochemical Voltammetry (including amperometry) Potentiometry Chemically sensitized field effect transistor Potentiometry with solid electrolytes for gas sensing... 

J2. Janata, J., and Huber, R. J., Chemically sensitive field effect transistors. In Ion Selective Electrodes in Analytical Chemistry" (H. Freiser, ed.), Vol. 2, pp. 107-174. Plenum, New York, 1980. 

Another important class of sensors is constituted by inorganic field-effect gas sensors, known as chemically sensitive field-effect transistors (CFIEMFETs) [28,31-35]. Their most successful application is in highly sensitive hydrogen sensors commercialized by Sensistor AB (Sweden) more than 15 years ago as leak detectors. They have proven over the years to be very reliable. A CHEMFET is essentially a... 

A. K. Covington and A. Sibbald, Offset-Gate Chemical-Sensitive Field Effect Transistor with Electrolytically Programmable Selectivity. Eur. Pat. Appl. No. 821124, (1982). 

Chemically sensitive field effect transistors are called CHEMFETs. If the coating of the gate of the FET is gas-sensitive, the term GASFET is used instead. When the polymer acts as an ion exchanger with protons or other ions, it results in a pH-sensitive or ion-sensitive device called a pH-FET or ISFET. For instance, a potassium-sensitive device is called a K-ISFET. 

Chemical modulation of work function (WF) is one mode of transduction on which a whole new class of chemical sensors can be based [49]. The measurement of WF requires that the chemically sensitive layer is capaci-tively coupled to the rest of the sensor at one interface. This requirement is satisfied in the vibrating capacitor (Kelvin probe) and in all solid-state devices utilizing the insulated gate. Typical examples are so-called chemically sensitive diodes and chemically sensitive field-effect transistors. 

Janata, J. Electrochemistry of chemically sensitive field effect transistors. Sens. Actuat. B 4, 255-265 (1983)... 

It was established that IL-based chemically sensitive field-effect transistors and quartz crystal microbalance sensors can be developed as well (see, e.g.. Fig. 7.4). For example, chemically sensitive field-effect transistors based on a composite of camphorsulfonic acid (CSA)-doped polyaniline (PAN) and an IL of 1-butyl-3-methylimidazolium bis(trifluoromethanesulfonyl)-imide, BMI(Tf,N) could... 

Electrochemical sensors, among them voltammetric and potentiometric devices, chemically sensitized field effect transistor (CHEMFET) and potentiometric soHd electrolyte gas sensors... 

CHEMFET devices or chemically sensitive field-effect transistors are potentiometric devices in which the metal layer of a solid-state insulated gate field-effect transistor (IGFET) f29] is replaced with a chemically sensitive electroconductive polymer membrane film. Changes in polymer membrane potential modulate the drain impedance of the space-charge region beneath the insulator. The result is a change in drain current /o under a fixed drain voltage Vd- The potential of the membrane may be modulated in the standard way (as in po-tentiometry, above) or may be modulated by an inert electrode placed beneath the film (but isolated from both the source and drain electrodes) and connected to an efficient electrode for the candidate analyte [30]. 

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