High-response and low-power-consumption CO micro gas sensor based on nano-powders and a micro-heater

In this research, a CO micro gas sensor was fabricated based on a micro-heater by using a tin oxide nano-powder for effective gas detection and a monitoring system with low power consumption and high sensitivity. Tin-oxide-based nano-powders were fabricated using a conventional method and their structural properties were examined by using the scanning electron microscope, X-ray diffractor, etc. Membrane type micro-heater based on Si substrate was fabricated by using complementary metal-oxide semiconductor (CMOS) compatible micro electro mechanical systems (MEMS) process by using bulk micromachining. The gas sensing properties for slurry-dropped tin oxide thick film device were measured for CO gas. The micro gas sensors showed high sensitivity and low power consumption, about 15 mW power consumption, 2 ppm CO could be detected.