MEMS-based microheaters integrated gas sensors

Abstract

In the present work efforts have been made to develop microheater integrated gas sensors with low power consumption. The design and simulation of a single-cell microheater is carried out using ANSYS. Low power consumption (<35 mW) platinum micro-heater has been fabricated using bulk micromachining technique on silicon dioxide membrane (1.5 μm thin), which provided improved thermal isolation of the active area of 250 × 250 μm². The micro-heater has achieved a maximum temperature of ∼950 °C at an applied dc voltage of 2.5 V. Fabricated mircro-heater has been integrated with SnO₂ based gas sensors for the efficient detection of H₂ and NO₂ gases. The developed sensors were found to yield the maximum sensing response of ∼184 and ∼2.1 with low power consumption of 29.18 and 34.53 mW towards the detection of 1 ppm of NO₂ gas and 500 ppm of H₂ gas, respectively.

Keywords:

• Micro-heaters
• MEMs
• gas sensor
• semiconducting thin film

Acknowledgments

Authors are thankful to CEERI, Pilani for providing ANSYS Software to carry out the theoretical simulation work.