Investigation of Stability of the pH-Sensitive Field-Effect Transistor Characteristics

摘要

The drift of threshold voltage of the p-channel ion-selective field-effect transistors with induced channel caused by long-term influence of negative voltage applied to the channel area through the two-layer SiO_2/Si_3N_4 gate dielectric is investigated. Based on the experimental data a mechanism of the observed instability is proposed and corresponding design and technology enhancements improving sensor stability for prolonged continuous measurements are outlined.