Gas-Sensitive Semiconductor Field-Effect Sensors

摘要

Modified silicon field-effect transistor (FET) and MIS-diodes as well as semiconducting metal oxides were examined for their suitability for the detection of CO, CO2, SO2, NO, N2O, and NH3 gases. The channel conductivity of silicon semiconductor structures was field controlled by the effect of gases and vapours on a sensitive layer of organic material, zeolite or palladium. The conductivity of the material changed for semiconductor oxides. There was no success with gas sensors having organic layers or zeolite. The selective detection of H2 was achieved using MIS-diodes with palladium. Oxidisable gases in air could be detected with the semiconducting metal oxide gas sensors. An increase in sensitivity was achieved compared with established systems and the first indication of selective gas detection was observed.