PROJECT TITLE :

Drift-Free pH Detection With Silicon Nanowire Field-Effect Transistors

ABSTRACT:

The drift of drain current ( $I_D)$ in silicon nanowire field-impact transistor sensors is analyzed below numerous conditions of pHs and liquid gate voltages ( $V_LG)$ . It is found that H+ penetration into Helmholtz layer or sensing insulator is the reason for the current drift. To suppress the drift, a unique and quick measurement technique with a two-step $V_LG$ is proposed and demonstrated. The drift might be utterly suppressed by controlling the period of the first step pulse. The time required to get rid of the $I_D$ drift is considerably reduced by the proposed method, from $sim 120zero$ s to below 100 s on average.