A wafer-bonded floating-element shear stress microsensor with optical position sensing by photodiodes

Author

Padmanabhan, Aravind ; Goldberg, Howard ; Breuer, Kenneth D. ; Schmidt, Martin A.

Author_Institution

Microsystems Technol. Lab., MIT, Cambridge, MA, USA

Volume

5

Issue

4

fYear

1996

fDate

12/1/1996 12:00:00 AM

Firstpage

307

Lastpage

315

Abstract

This paper discusses a noninvasive sensing technique for the direct measurement of low-magnitude shear stresses in laminar and turbulent air flows. The sensing scheme detects the flow-induced in-plane displacement of a microfabricated floating-element structure (500 μm×500 μm×7 μm), using integrated photodiodes. The wall-mounted floating-element sensors were fabricated using a wafer-bonding technology. The sensors were calibrated in a custom-designed laminar flow cell and subsequently shown to be able to transduce shear stresses of 0.01 Pa during tests in a low-speed wind tunnel

Keywords

calibration; laminar flow; micromachining; microsensors; optical sensors; photodiodes; stress measurement; turbulence; wafer bonding; calibration; custom-designed laminar flow cell; direct measurement; floating-element microsensor; flow-induced in-plane displacement; integrated photodiodes; laminar air flows; low-magnitude shear stresses; microfabricated floating-element structure; noninvasive sensing technique; optical position sensing; optical shear stress microsensor; photodiodes; turbulent air flows; wafer-bonding technology; wall-mounted sensors; Atmospheric measurements; Extraterrestrial measurements; Fluid flow measurement; Microsensors; Optical sensors; Photodiodes; Sensor phenomena and characterization; Space technology; Stress measurement; Testing;

fLanguage

English

Journal_Title

Microelectromechanical Systems, Journal of

Publisher

ieee

ISSN

1057-7157

Type

jour

DOI

10.1109/84.546410

Filename

546410