Sloped-Gate Voltage Method for Improving Measurement of Poly-Si Nanowire FET in Aqueous Environment

Abstract

Nanowire field-effect transistors are suited to study the activity of biomolecules in bionanotechnology. The changes of biomolecules process are efficiently affected the charge at the nanowire surface; thus, the electrical characterization of NW-FET is changed. Although NW-FET is a well-known device in bioapplications, however, the intrinsic electrical characterization of NW-FET effect on real electrical measurement is not well studied. We present herein a novel measurement method to avoid errors in electrical characteristic of nanowire field-effect transistors. A physical model is developed to explore the effect of the leakage current, which is influenced by the charging effect of an equivalent capacitor in a NW-FET. We also present a sloped-gate voltage method to reduce the effect of equivalent capacitor in air, liquid, and phosphate buffered solution. The application of the sloped-gate voltage method significantly increases the stability of electrical characterization measurements. This method can also be easily applied to biosensing experiments.

(Invited) The Next Generation Biochip

“…In aqueous environment, intrinsic electrical properties of pSNWFET may affect real electrical measurement. We develop a novel sloped-gate voltage method for improving measurement of pSNWFET in aqueous environment (4). A physical model is developed to explore the effect of the leakage current, which is influenced by the charging effect of an equivalent capacitor in a pSNWFET.…”