Title | Microfabricated silicon-on-Pyrex passive wireless wall shear stress sensor |
Publication Type | Conference Paper |
Year of Publication | 2011 |
Authors | Sells, J., V. Chandrasekharan, J. Meloy, M. Sheplak, H. Zmuda, and D. P. Arnold |
Conference Name | 2011 IEEE Sensors2011 IEEE SENSORS Proceedings |
Publisher | IEEE |
Conference Location | Limerick, Ireland |
ISBN Number | 978-1-4244-9288-6 |
Abstract | This paper presents the design, fabrication, and characterization of a passive wireless sensor for the measurement of wall shear stress. A micromachined variable-capacitor shear stress transducer is realized using a silicon-on-Pyrex microfabrication process. The design features a diamond-shaped 2.25 mm2 silicon floating-element to accommodate more comb fingers for improved capacitive transduction in a smaller die area. The variable-capacitor device is connected to a fixed inductor on a printed circuit board to enable passive wireless sensing. The nominal resonant frequency of the device is 168 MHz with a quality factor of 8.6. Calibrations of static shear stress in a flow cell show a linear response to over 4 Pa, with a frequency-shift sensitivity of 474 kHz/Pa (1.1% full scale). Theoretically a minimum detectable shear stress of 4.1 mPa can be resolved giving a 61.7 dB dynamic range. |
DOI | 10.1109/ICSENS.2011.6127352 |
Refereed Designation | Refereed |