Molecular Gating of Silicon Nanowire Field-Effect Transistors with Nonpolar Analytes
- 23 December 2011
- journal article
- research article
- Published by American Chemical Society (ACS) in ACS Nano
- Vol. 6 (1), 335-345
- https://doi.org/10.1021/nn203653h
Abstract
Silicon nanowire field-effect transistors (Si NW FETs) have been used as powerful sensors for chemical and biological species. The detection of polar species has been attributed to variations in the electric field at the conduction channel due to molecular gating with polar molecules. However, the detection of nonpolar analytes with Si NW FETs has not been well understood to date. In this paper, we experimentally study the detection of nonpolar species and model the detection process based on changes in the carrier mobility, voltage threshold, off-current, off-voltage, and subthreshold swing of the Si NW FET. We attribute the detection of the nonpolar species to molecular gating, due to two indirect effects: (i) a change in the dielectric medium close to the Si NW surface and (ii) a change in the charged surface states at the functionality of the Si NW surface. The contribution of these two effects to the overall measured sensing signal is determined and discussed. The results provide a launching pad for real-world sensing applications, such as environmental monitoring, homeland security, food quality control, and medicine.Keywords
This publication has 38 references indexed in Scilit:
- Enhanced Sensing of Nonpolar Volatile Organic Compounds by Silicon Nanowire Field Effect TransistorsACS Nano, 2011
- Nanomaterials for cross-reactive sensor arraysMRS Bulletin, 2010
- Subthreshold Regime has the Optimal Sensitivity for Nanowire FET BiosensorsNano Letters, 2009
- Semiconducting Nanowire Field-Effect Transistor Biomolecular SensorsIEEE Transactions on Electron Devices, 2008
- Highly ordered nanowire arrays on plastic substrates for ultrasensitive flexible chemical sensorsNature Materials, 2007
- Nanowire electronic and optoelectronic devicesMaterials Today, 2006
- Toward the Nanoscopic “Electronic Nose”: Hydrogen vs Carbon Monoxide Discrimination with an Array of Individual Metal Oxide Nano- and Mesowire SensorsNano Letters, 2006
- Nanowire nanosensorsMaterials Today, 2005
- Electrical detection of single virusesProceedings of the National Academy of Sciences of the United States of America, 2004
- Nanowire Nanosensors for Highly Sensitive and Selective Detection of Biological and Chemical SpeciesScience, 2001