Pt/mixed Al2O3 and Ga2O3 reactive insulator/AlGaN metal-insulator-semiconductor (MIS)-type hydrogen sensors were fabricated using a photoelectrochemical oxidation method to directly oxidize AlGaN employed for increasing the sensor response to hydrogen gas. When hydrogen gas was sensed, the MIS hydrogen sensors exhibited a larger reduction of the barrier height and series resistances than that of the Pt/AlGaN metal-semiconductor (MS)-type hydrogen sensors. As a result, the MIS hydrogen sensors could detect the hydrogen concentration lower than 100 ppm H2 /air while the MS hydrogen sensors could not detect such low hydrogen concentration. This provides a promising potential candidate of using a mixed Al2 O3 and Ga2O3 insulator for AlGaN-based hydrogen gas sensors.
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Renewable Energy, Sustainability and the Environment
- Surfaces, Coatings and Films
- Materials Chemistry