Performance of hydrogen-sensitive MOS capacitances with integrated on-chip signal conditioning

Gas-sensitive MOS capacitors with on-chip readout electronics are investigated. The use of these capacitors in combination with switched capacitor circuitry enables a.c. operation of the device to take place. Measurements show an improved long-term stability. A comparison between the integrated sensor system and a gas-sensitive FET integrated on the same chip allows these different types of sensors to be directly compared.