Comprehensive Study of Pd/GaN Metal-Semiconductor-Metal Hydrogen Sensors with Metal-Oxide Mixture

We demonstrate a metal-semiconductor-metal Pd/GaN hydrogen sensor with a porous-like mixture of Pd and SiO2. Beside the symmetrically bidirectional sensing characteristics with a widespread voltage regime ranging at least from −5 to 5 V, a high sensing response of 8 × 105 and 7.7 × 106 corresponding to a Schottky barrier height variation of 352 and 411 meV is obtained in a 4890-ppm H2/N2 ambience at a voltage of −1.5 and −5 V, respectively. A highly efficient dissociation of hydrogen molecules due to an enhanced catalytic activity of the mixture explains the improved performance. Furthermore, dynamic responses by alternately switching the voltage polarity and introducing and removing hydrogen-containing gases are also included to evaluate the proposed device as a high sensing response and low power sensor. These statements are an example of what a properly prepared meeting abstract should look like. Proper column and margin measurements are also indicated.