Study on Single Chip Integrated Methane Sensor based on MEMS Process

Abstract

For decades, globular black-white catalytic gas sensor has the problems of handmade, large element dispersion and matching difficulty. To solve these problems, with combination of silicon-based MEMS technology and nanometer technology, an idea of integrating sensitive components of catalytic sensors and compensation components together into a chip is proposed. $\gamma$-Al2O3/ZrO2 active carriers are created using chemical co-precipitation method and stabilization modification with ThO2+CeO2using doping technology (Pd and Pt as catalysts). In order to fabricate catalytic gas sensors with integration, sensor chip and heat sensitive electrode are manufactured by silicon MEMS and high pure platinum film production process so that the catalytic sensitive elements and temperature-humidity compensating element can be integrated on micro bridge. The results show that the sensor has a fast response to methane gas, with 90% response time of 10s and recovery time of 12s. The average sensitivity of the sensor output is 15mv/1%CH4.