Development of Micro-hotplate with TaN Heater Based Cu-doped SnO2 Gas Sensor for Low Concentration of H2S Gas

Abstract

In this study, the MEMS-based SnO2 gas sensor with a TaN heater, MSGST, was designed and fabricated using micromachining technology. The heating performance of the TaN heater was measured using an IR thermometer. The response of the MSGST sensor to H2S gas was analyzed by obtaining the relationship between the resistance of the sensor and the gas concentration to determine the best design parameters. Experimental results indicate that a MEMS-based SnO2 gas sensor, integrating TaN with a micro-hotplate, was successfully implemented using micromachining technology. The TaN heater can operate at over 300 degrees C and produce a uniform thermal distribution on the micro-hotplate. The sensitivity of the MSGST sensor to the H2S gas is significantly improved using a Cu catalyst and the optimal design parameters (Sensing film = 100 mu m(2), Cu catalyst = 7.5 mM) are obtained by measuring the gas concentration characterization for each the designed sensor.