Title :
The accurate measurement of a micromechanical force using force-sensitive capacitances
Author :
Wolffenbuttel, M.R. ; Regtien, P.P.L.
Author_Institution :
Dept. of Electr. Eng., Delft Univ. of Technol., Netherlands
fDate :
4/1/1995 12:00:00 AM
Abstract :
A sensor for the precise and accurate measurement of micromechanical forces is presented. The sensor is based on the capacitive detection of force-induced deflection of a microstructure and integrated charge readout. The mechanical performance of the sensor is evaluated and verified with experiments. The structure has been designed to enable the separation of the force-to-deflection and deflection measurements in order to result in a sensor structure in which the response is linear with force and little affected by fringe fields. The sensor is 0.25 mm2 in size and has a force range of 0.2 mN, a zero-force capacitance of 0.5 pF, a sensitivity of 1-5 fF/μN, and a resolution that corresponds to a capacitance variation of 2 fF
Keywords :
electric sensing devices; force measurement; microsensors; 0.5 pF; capacitive detection; deflection measurements; force-induced deflection; force-sensitive capacitances; fringe fields; integrated charge readout; mechanical performance; micromechanical force; microstructure; sensor structure; zero-force capacitance; Capacitance measurement; Capacitive sensors; Electrodes; Force measurement; Force sensors; Mechanical sensors; Micromechanical devices; Sensor phenomena and characterization; Silicon; Springs;
Journal_Title :
Instrumentation and Measurement, IEEE Transactions on
