Pulsed Method for Characterizing Aqueous Media Using Nanowire Field Effect Transistors

This paper presents a method for using nanowire field-effect transistors (NW-FETs) as sensors in aqueous solutions without the need for a reference electrode. A pulsed-gate potential method is used to reduce instabilities related to the dynamics of ions and other charged species present in the solution. Application of this method results in a significant increase in the stability of the electrical properties of the devices, enabling reproducible characterization of aqueous media with NW-FETs. We show that this method can be applied to perform pH measurements with a silicon NW-FET.