Title :
A metal-on-silicon differential capacitive shear stress sensor
Author :
Chandrasekharan, V. ; Sells, J. ; Meloy, J. ; Arnold, D.P. ; Sheplak, M.
Author_Institution :
Interdiscipl. Microsyst. Group, Univ. of Florida, Gainesville, FL, USA
Abstract :
The paper presents a direct, capacitive shear stress sensor with performance sufficient for time-resolved turbulence measurements. The device employs a bulk-micromachined, metal-plated, differential capacitive floating-element design. A simple, two-mask fabrication process is used with DRIE on an SOI wafer to form a tethered floating element structure with comb fingers for transduction. Experimental results indicate a linear sensitivity of 7.66 mV/Pa up to the testing limit of 1.9 Pa at a bias voltage of 10 V , and a bandwidth of 6.2 kHz . The sensor possesses a dynamic range Gt 102 dB and a noise floor of 14.9 muPa/radic(Hz) at 1 kHz , outperforming previously reported sensors by nearly two orders of magnitude in MDS.
Keywords :
capacitive sensors; microfabrication; microsensors; passivation; silicon-on-insulator; SOI wafer; capacitive shear stress sensor; differential capacitive floating-element design; metal-on-silicon differential capacitive sensor; tethered floating element structure; time-resolved turbulence measurements; two-mask fabrication process; Bandwidth; Capacitive sensors; Electromagnetic interference; Fabrication; Fingers; Nickel; Packaging; Stress measurement; Temperature sensors; Thermal stresses; Shear stress sensor; capacitive sensors; comb fingers; metal passivation;
Conference_Titel :
Solid-State Sensors, Actuators and Microsystems Conference, 2009. TRANSDUCERS 2009. International
Conference_Location :
Denver, CO
Print_ISBN :
978-1-4244-4190-7
Electronic_ISBN :
978-1-4244-4193-8
DOI :
10.1109/SENSOR.2009.5285808
