Abstract
A novel approach for the ion-sensing of electrolyte solution, using specially designed CMOS FinFET process compatible floating-gate (FG) device is proposed. With the self-balancing readout scheme, the floating gate based pH sensor shows a maximum pH readout sensitivity of 115 mV/pH. Through a laterally coupling structure to the metal floating gate of a FinFET, its channel potential can be controlled both by the read gate as well as the sensing gate. In additional, this novel scheme also enables high linearity pH sensing in the target sensing range, readily adjusted by coupling ratios and biasing levels.