Biosensors based on nanowire field effect transistors with Schottky contacts

T E Smolyarova,L V Shanidze,A S Tarasov,F V Zelenov,I A Yakovlev,N V Volkov,A V Lukyanenko,F A Baron

doi:10.1088/1742-6596/1410/1/012013

Abstract

A top-down nanofabrication approach was used to obtain silicon nanowires from silicon-on-insulator wafers using direct-write electron beam lithography and plasma-reactive ion etching. Fabricated with designed pattern silicon nanowires are 0.4, 0.8, 2 μm in width and 100 nm in height. The devices can be applied in future medical diagnostic applications as novel biosensors with detection principle based on the changes in electrical characteristics of the silicon nanowires functionalized with thiol-containing molecules.

Highlights

Nanometer-scale structures, in silicon nanowires (NW), attract considerable attention due to their possible application in nanotechnology and nanomedicine since their sizes are comparable to the sizes of chemical and biological species for detection
The sensing mechanism of such devices may be described in terms of the change in charge density, which induces a change in the electric field at the silicon nanowire surface
Taking into account the advantages of “topdown” approach, we report nanofabrication technology of biosensor based on Schottky barrier nanowire FET using electron beam lithography (EBL) process and chemical wet and plasma-reactive ion etching (RIE), the functionalization process of nanowire surface using the tip of atomic-force microscope and the results of thiol molecules detection

Summary

Introduction

Nanometer-scale structures, in silicon nanowires (NW), attract considerable attention due to their possible application in nanotechnology and nanomedicine since their sizes are comparable to the sizes of chemical and biological species for detection. At that time in integrated nanoscale electronics the considerable attention is paid to devices based on Si NWs with Schottky contacts [1,2]. The most popular method for fabrication of such devices in nanoscale is “top-down” synthesis approach [14,15,16,17,18,19], which allow to regulate device geometry and electrical characteristics due to precise control of lateral sizes of nanowire and enables direct contact with other structures on device. Taking into account the advantages of “topdown” approach, we report nanofabrication technology of biosensor based on Schottky barrier nanowire FET using electron beam lithography (EBL) process and chemical wet and plasma-reactive ion etching (RIE), the functionalization process of nanowire surface using the tip of atomic-force microscope and the results of thiol molecules detection

Methods

Results

Conclusion