Pt/Ga2O3/SiC MRISiC devices: A study of the hydrogen response

The electrical properties of Pt/Ga2O3/SiC metal oxide semiconductor devices are presented in this paper in order to determine the hydrogen sensing mechanism. This was achieved by studying the role of the interface states upon the introduction of hydrogen/hydrocarbon gas. Current-voltage (I-V), conductance-voltage (C-V) and capacitance-voltage (G-V) experiments have been carried out to investigate the gas sensing mechanism. The devices' hydrogen and propene gas sensitivities were also investigated. This was achieved by operating them as Schottky diodes and by measuring the change in output voltage when kept at a constant forward bias current. Voltage shifts over 1 V were observed. A discussion is also presented on the effect of operating temperature and ambient gas on the sensors' hydrogen response mechanism, which is attributed largely to the passivation and creation of energy states at the Ga2O3/SiC interface.