TY  - JOUR
A1  - Miyamoto, Ko-ichiro
A1  - Hayashi, Kosuke
A1  - Sakamoto, Azuma
A1  - Werner, Frederik
A1  - Wagner, Torsten
A1  - Schöning, Michael Josef
A1  - Yoshinobu, Tatsuo
T1  - A high-Q resonance-mode measurement of EIS capacitive sensor by elimination of series resistance
T2  - Sensor and Actuators B: Chemical
N2  - An EIS capacitive sensor is a semiconductor-based potentiometric sensor, which is sensitive to the ion concentration or pH value of the solution in contact with the sensing surface. To detect a small change in the ion concentration or pH, a small capacitance change must be detected. Recently, a resonance-mode measurement was proposed, in which an inductor was connected to the EIS capacitive sensor and the resonant frequency was correlated with the pH value. In this study, the Q factor of the resonant circuit was enhanced by canceling the internal resistance of the reference electrode and the internal resistance of the inductor coil with the help of a bypass capacitor and a negative impedance converter, respectively. 1% variation of the signal in the developed system corresponded to a pH change of 3.93 mpH, which was about 1/12 of the conventional method, suggesting a better performance in detection of a small pH change.
KW  - Negative impedance convertor
KW  - Resonance-mode measurement
KW  - Chemical sensor
KW  - EIS capacitive sensor
Y1  - 2017
UR  - https://opus.bibliothek.fh-aachen.de/opus4/frontdoor/index/index/docId/8146
SN  - 0925-4005
VL  - 248
SP  - 1006
EP  - 1010
PB  - Elsevier
CY  - Amsterdam
ER  -