Micro-machined resistive micro-heaters for high temperature gas sensing applications

Presented for the first time is the design and fabrication of novel high temperature, low power consumption, and good thermal uniformity micro-heaters for environmental gas sensors. A O/N/O (SiO₂/Si_xN_y/SiO₂) structure of membrane was used for stress compensation and thermal isolation. A Wheatstone-bridge type resistive Pt heating structure and a multi-ringed heat spreading structure was applied to enhance the thermal uniformity. Results show that these fabricated heaters can operate at a high temperature, have low power consumption and good thermal uniformity. The thermal efficiency of the fabricated micro-heaters is 36degC/mW.