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Title: A Fringe Field Shaping CMOS Capacitive Imaging Array
While classical electrochemical impedance spectroscopy (EIS) focuses on measurements from a single working electrode, dense active microelectrode arrays offer opportunities for new modes of sensing. Here we present experimental results with an integrated sensor array for electrochemical imaging. The system uses a 100 x 100 custom CMOS electrode array with 10 micron pixels, which measures impedance at frequencies up to 100 MHz. The sensor chip is uniquely designed to take advantage of the electrostatic coupling between groups of nearby pixels to re-shape the local electric field. Multiple bias voltages and clock phases create new types of signal diversity that will enable enhanced sensing modes for computational imaging and impedance tomography.  more » « less
Award ID(s):
2027108
NSF-PAR ID:
10322165
Author(s) / Creator(s):
; ;
Date Published:
Journal Name:
2021 IEEE Sensors Conference
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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