Investigation of Metrological Performance of the ISFET-Based pH Sensors

Abstract

The metrological performance characteristics of the dual channel p-type ISFET pH sensors with silicon nitride sensitive layer are investigated. The simplified three-lead sensor design and corresponding signal readout circuit are employed and the sensor transform function is evaluated as dependency of the ISFET channel current on the analyzed solution pH. It is shown that achievable pH measurement accuracy is sufficient for use of the developed sensors in typical laboratory applications in either single channel or differential mode of operation, as alternative to the traditional glass electrodes.

Keywords

• Ion-sensitive field effect transistor
• ISFET
• Biosensor
• pH Measurement
• Sensitivity
• Accuracy