Microsystem Technologies

, Volume 15, Issue 8, pp 1201–1205

A microcantilever-based gas flow sensor for flow rate and direction detection

  • Rong-Hua Ma
  • Po-Cheng Chou
  • Yu-Hsiang Wang
  • Tzu-Han Hsueh
  • Lung-Ming Fu
  • Chia-Yen Lee
Technical Paper

Abstract

Utilizing conventional micro-electro-mechanical systems techniques, this study fabricates and characterizes a novel micro gas flow sensor comprising four silicon nitride/silicon wafer cantilever beams arranged in a cross-form configuration. The residual stresses induced within the beams during their fabrication cause the tip of each beam to curve slightly in the upward direction. However, as air travels over the surface of the sensor, the upstream cantilevers are deflected in the downward direction, while the downstream cantilevers are deflected in the upward direction. The velocity of the air flow is then determined by measuring the corresponding change in resistance of the piezoresistors patterned on the upper surface of each cantilever beam. It is shown that by measuring the change in resistance of all four cantilever beams, the proposed sensor can detect not only the velocity of the air flow, but also its direction.

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Copyright information

© Springer-Verlag 2008

Authors and Affiliations

  • Rong-Hua Ma
    • 1
  • Po-Cheng Chou
    • 2
  • Yu-Hsiang Wang
    • 3
  • Tzu-Han Hsueh
    • 3
  • Lung-Ming Fu
    • 4
  • Chia-Yen Lee
    • 4
  1. 1.R.O.C. Military AcademyKaohsiungTaiwan
  2. 2.Shu-Te UniversityKaohsiungTaiwan
  3. 3.Da-Yeh UniversityChanghuaTaiwan
  4. 4.National Pingtung UniversityPingtungTaiwan

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