Biological information (pH/EC) sensor device for quantitatively monitoring plant health conditions

In this study, a sensor device based on MEMS technology is proposed to quantitatively monitor the health conditions of plants using biological information (i.e., pH and electrical conductivity (EC)). The proposed sensor device comprises an ion-sensitive field-effect transistor (ISFET)-based sensor (for pH measurement), an EC sensor, and a p-n diode temperature sensor (for adjusting the temperature dependency of the pH and EC measurements). A prototype of the proposed sensor device was fabricated. Furthermore, the basic performance of the ISFET-based pH sensor and EC sensor was evaluated. Through experiments with mimicking plant, the feasibility of measuring the internal biological information (pH and EC) of plants was demonstrated.