Cart (Loading....) | Create Account
Close category search window
 

First Observation of Hydrogen sensing by Trap Assisted Conduction Current in Pd/TiO2/SiC Capacitors at High Temperature

Sign In

Cookies must be enabled to login.After enabling cookies , please use refresh or reload or ctrl+f5 on the browser for the login options.

The purchase and pricing options are temporarily unavailable. Please try again later.
4 Author(s)
Weng, Ming-Hung ; Univ. of Newcastle, Newcastle upon Tyne ; Horsfall, A. ; Mahapatra, Rajat ; Wright, N.

This paper reports the first observation of gas sensing using the leakage current through a capacitor fabricated on silicon carbide (SiC). The dielectric layer used in this sensor has a titanium dioxide layer in addition to the thermally grown silicon dioxide (SiO2) and this operates as an adhesion promoting layer to the catalytic metal gate contact. We have shown that the leakage current through this Pd/TiO2/SiO2/SiC capacitor structure is controlled by a trap assisted tunneling mechanism, using a single barrier height and trap density. This barrier height is lowered in the presence of hydrogen gas at high temperatures, whilst the trap density in the dielectric remains unchanged. This shows that the formation of a charge dipole layer under the contact is responsible for the observed change in characteristics in the hydrogen environment, rather than a change to the bulk properties of the dielectric layer. Further, we show that this technique is not affected by the influence of interface traps, which dominate the low voltage capacitance characteristics at high temperatures, offering the opportunity for a simple, more rugged detection method.

Published in:

Sensors, 2006. 5th IEEE Conference on

Date of Conference:

22-25 Oct. 2006

Need Help?


IEEE Advancing Technology for Humanity About IEEE Xplore | Contact | Help | Terms of Use | Nondiscrimination Policy | Site Map | Privacy & Opting Out of Cookies

A not-for-profit organization, IEEE is the world's largest professional association for the advancement of technology.
© Copyright 2014 IEEE - All rights reserved. Use of this web site signifies your agreement to the terms and conditions.