Investigation on the sensitivity of hot-plate gas flow sensors in very low flow regime

The diffusion of thermal gas flow sensors in the field of microfluidic, biomedic and aerospace applications has led to a growing request for more and more accurate devices suitable for very low flow rate. In this work, a theoretical and experimental investigations of the response of a micromachined silicon anemometer in very low gas flow rate is reported. In particular, the dynamical range and sensitivity limits of the presented thermal sensor have been investigated. Possible solutions aimed to increase the sensor performances have been also proposed and discussed.