Integrated Pre-Concentrator Gas Sensor System For Improved Trace Gas Sensing Performance

An integrated gas measurement system is presented which combines MEMS gas sensors with a micro gas pre-concentration device. Designed to increase gas sensor selectivity and sensitivity, the pre-concentrator samples gases and releases them by thermal desorption. Simulations show that the design works very well for volatile organic compounds in the ppb concentration range, which would be the target gases in indoor air quality monitoring. A gas concentration increase of a factor of 27 was achieved in the presented setup of the simulation. In test measurements with benzene, the successful operation of the integrated system is demonstrated for concentrations down to 10 ppb. The height of the sensor response was nearly doubled during pre-concentrator gas desorption.