2003 Volume 71 Issue 6 Pages 394-397
A fabricated hydrogen sensor diode of Pt - thin TiOx layer - SiC structure was found to exhibit a large voltage response up to 3 volts. Diodes with and without the TiOx layer were compared in terms of current-voltage characteristics. The difference in voltage obtained in an H2 atmosphere and that obtained in an O2 atmosphere at a constant forward current was studied. A simple model consisting of a resistance and Schottky diode connected in series was assumed. The voltage change results from changes in both barrier height and series resistance. The change in series resistance is due to a property of TiOx under exposure to hydrogen.