Sense Piezoresistor Pressure Glass Support URE 56.3 Schematic cross section of a silicon piezoresistive pressure sensor. A differential pressure deforms the hragm, producing strain in the integrated piezoresistor. The change in resistance is measured via a wheatstone e bride. Defining Terms Micromachining: The set of processes which produce three-dimensional microstructures using sequential photolithographic pattern transfer and etching or deposition in a batch processing method. Microsensor: A sensor which is fabricated using integrated circuit and micromachining technologies Repeatability: The ability of a sensor to reproduce output readings for the same value of measurand, when Sensitivity: The ratio of the change in sensor output to a change in the value of the measurand. Sensor: A device which produces a usable output in response to a specified measurand Stability: The ability of a sensor to retain its characterisctics over a relatively long period of time Related Topics 58.6 Smart Sensors. 114.1 Introduction. 114.2 Physical Sensors. 114.3 Chemical Sensors. 114.4 Bioa alytical Sensors. 114.5 Applicatio References ANSI," Electrical Transducer Nomenclature and Terminology, ANSI Standard MC6. 1-1975(ISA S37.1) Research Triangle Park, N.C.: Instrument Society of America, 1975 D.S. Ballentine, Jr et al, Acoustic Wave Sensors: Theory, Design, and Physico-Chemical Applications, San Diego, Calif: Academic Press, 1997. A J. Bard and L. R. Faulkner, Electrochemical Methods: Fundamentals and Applications, New York: John wiley &Sons,1980 R.S. C Cobbold, Transducers for Biomedical Measurements: Principles and Applications, New York: John wiley &Sons,1974. Gopel, J. Hesse, and J. N. Zemel, Eds, Sensors: A Comprehensive Survey, vol. 1, Fundamentals and general Aspects, T. Grandke and W. H. Ko, Eds, Weinheim, Germany: VCH, 1989 J Janata, Principles of Chemical Sensors, New York, Plenum Press, 1989 c 2000 by CRC Press LLC© 2000 by CRC Press LLC Defining Terms Micromachining: The set of processes which produce three-dimensional microstructures using sequential photolithographic pattern transfer and etching or deposition in a batch processing method. Microsensor: A sensor which is fabricated using integrated circuit and micromachining technologies. Repeatability: The ability of a sensor to reproduce output readings for the same value of measurand, when applied consecutively and under the same conditions. Sensitivity: The ratio of the change in sensor output to a change in the value of the measurand. Sensor: A device which produces a usable output in response to a specified measurand. Stability: The ability of a sensor to retain its characterisctics over a relatively long period of time. Related Topics 58.6 Smart Sensors • 114.1 Introduction • 114.2 Physical Sensors • 114.3 Chemical Sensors • 114.4 Bioan￾alytical Sensors • 114.5 Applications References ANSI, “Electrical Transducer Nomenclature and Terminology,” ANSI Standard MC6.1-1975 (ISA S37.1), Research Triangle Park, N.C.: Instrument Society of America, 1975. D. S. Ballentine, Jr. et al., Acoustic Wave Sensors: Theory, Design, and Physico-Chemical Applications, San Diego, Calif.: Academic Press, 1997. A. J. Bard and L. R. Faulkner, Electrochemical Methods: Fundamentals and Applications, New York: John Wiley & Sons, 1980. R. S. C. Cobbold, Transducers for Biomedical Measurements: Principles and Applications, New York: John Wiley & Sons, 1974. W. Göpel, J. Hesse, and J. N. Zemel, Eds., Sensors: A Comprehensive Survey, vol. 1, Fundamentals and General Aspects, T. Grandke and W. H. Ko, Eds., Weinheim, Germany: VCH, 1989. J. Janata, Principles of Chemical Sensors, New York, Plenum Press, 1989. FIGURE 56.3 Schematic cross section of a silicon piezoresistive pressure sensor. A differential pressure deforms the silicon diaphragm, producing strain in the integrated piezoresistor. The change in resistance is measured via a Wheatstone bridge