Fabrication of micro heaters on polycrystalline 3C-SiC suspended membranes for gas sensors and their characteristics

This paper describes the design, fabrication, and characteristics of micro heaters mad on AlN (0.1 μm)/3C-SiC (1 μm) suspended membranes using surface micromachining technology. 3C-SiC and AlN thin films, which have a large energy band gap and very low lattice mismatch, were used for high-temperature environments. A Pt thin film was used as micro heaters and temperature sensor materials. The resistance of the temperature detector (RTD) and the power consumption of the micro heater were measured and calculated. The heater is designed for an operating temperature up to about 800 °C and can be operated at about 500 °C with a power of 312 mW. The thermal coefficient of the resistance (TCR) of fabricated Pt RTD’s is 3174.64 ppm/°C. The thermal distribution measured by IR thermovision is uniform across the membrane surface.