A Pt/Ga/sub 2/O/sub 3//SiC Schottky diode based hydrocarbon gas sensor

This paper presents the propene gas sensing performance of Pt/Ga/sub 2/O/sub 3//SiC based Schottky diodes. The metal oxide semiconducting Ga/sub 2/O/sub 3/ thin films were doped with Zn and prepared by the sol-gel process. The thin films were deposited onto the SiC by the spin coating technique and a Pt layer was deposited on the top of the metal oxide forming the Schottky diode. The sensor responses were stable and repeatable towards propene at operating temperatures between 300 and 600/spl deg/C. The diodes were biased at a constant current of 2 mA. When exposed to 1,900 ppm of propene at an operating temperature of 525/spl deg/C, a shift of 85 mV was observed.