Nanorod based Schottky contact gas sensors in reversed bias condition
- 10 June 2010
- journal article
- Published by IOP Publishing in Nanotechnology
- Vol. 21 (26), 265502
- https://doi.org/10.1088/0957-4484/21/26/265502
Abstract
There has been significant interest in using electronically contacted nanorod or nanotube arrays as gas sensors, whereby an adsorbate modifies either the impedance or the Fermi level of the array, enabling detection. Typically, such arrays demonstrate the I-V curves of a Schottky diode that is formed using a metal-semiconductor junction with rectifying characteristics. We show in this work that nanostructured Schottky diodes have a functionally different response, characteristic of the large electric field induced by the size scale of the array. Specifically, they are characterized by a low reverse breakdown voltage. As a result, the reverse bias current becomes a strong function of the applied voltage. In this work, for the first time, we model this unique feature by describing the enhancement effect of high aspect ratio nanostructures on the I-V characteristics of a Schottky diode. A Pt/ZnO/SiC nanostructured Schottky diode is fabricated to verify the theoretical equations presented. The gas sensing properties of the Schottky diode in reversed bias is investigated and it is shown that the theoretical calculations are in excellent agreement with measurements.This publication has 33 references indexed in Scilit:
- Hydrogen and hydrocarbon gas sensing performance of Pt/WO3/SiC MROSiC devicesSensors and Actuators B: Chemical, 2005
- Electrical and hydrogen sensing characteristics of Pd/ZnO Schottky diodes grown on GaAsSemiconductor Science and Technology, 2005
- Room temperature carbon monoxide sensor using ITO/n-GaAs Schottky contactSensors and Actuators B: Chemical, 2004
- Electrical Properties of Tin Dioxide Two-Dimensional NanostructuresThe Journal of Physical Chemistry B, 2004
- Current/voltage characteristics of a semiconductor metal oxide gas sensorSensors and Actuators B: Chemical, 2003
- Microstructure, dielectric properties and hydrogen gas sensitivity of sputtered amorphous Ba0.67Sr0.33TiO3 thin filmsMaterials Science and Engineering B, 2000
- High temperature Pt Schottky diode gas sensors on n-type GaNSensors and Actuators B: Chemical, 1999
- A study of hydrogen detection with palladium modified porous siliconAnalytica Chimica Acta, 1998
- Why bother about gas-sensitive field-effect devices?Sensors and Actuators A: Physical, 1996
- A novel PVD technique for the preparation of SnO2 thin films as C2H5OH sensorsSensors and Actuators B: Chemical, 1992