Highly Selective MEMS Gas Sensor Based on Temperature-Programmed Desorption Technology.

Aiming at the issue of poor selectivity in metal oxide gas sensors, a novel MEMS gas sensor structure was designed, comprising an adsorption unit and a sensing unit. Based on this design, a gas-sensing method utilizing on-chip programmable temperature analysis technology was developed. By quantifying the gas-sensitive response, we successfully extracted the peak signal of temperature-dependent resistance with high selectivity. The performance results show that ZSM-5, as the adsorbent material, exhibits desorption peak positions at different temperatures for four types of alcohol gases, and the peak height is correlated with the adsorption concentration. The essence of its high selectivity lies in the fact that materials have different desorption activation energies for different gases under the same conditions. This study proposes a new selective MEMS device testing method for identifying gas types and concentrations.