Gas sensors have become more and more important with the continuous improvement in the industry, because in many cases poisonous and combustible gases arose as by-products during manufacturing. It is essential to detect different gases, for instance, in case of safety equipment, human lives can depend on their proper operation.
In my paper, I discuss the structures of the different gas sensors, in particular metal-oxide based gas sensor and I try to demonstrate the mechanism of vanadium dioxide metal-insulator’s phase transition. In my work, I examined the behavior of vanadium dioxide thin films (produced by pulsed laser deposition and radio-frequency sputtering) in respect of in various gas composition environment, temperature falling near the metal- insulator transition and the temperature range from 150 to 200°C, and I take the current-voltage, the power-temperature and the resistance-temperature characteristics. I performed the tests with and without palladium-activated samples, furthermore i draw the conclusions and I offer further development opportunities.