Charge Transfer Type pH Sensor with Super High Sensitivity

Abstract

We successfully fabricated a super high sensitivity charge transfer type pH sensor. The proposed pH sensor is possible to amplify the sensing signals without an external amplifier by accumulation cycle. The pH sensitivity was obtained 5048 mV/pH, which is approximately 100 times higher than the Ion Sensitive Field Effect Transistor (ISFET), which is the most familiar pH sensor using semiconductor. This is the highest sensitivity of pH in the past. The performance of this charge transfer type pH sensor is equal with glass electrode type pH sensor. In addition, the charge transfer type pH sensor has much possibility to exceed the glass electrode method.