Non-Silicon MEMS Calorimetric Gas Flow Sensor

A novel non-silicon MEMS calorimetric gas flow sensor is presented. The sensor consists of a metal sensing/heating array placed over a glass substrate and a polyimide layer for passivation. Both the anti-pressure and anti- impact performance is enhanced by using a glass solid substrate instead of a common silicon suspending structure. This merit widens the application range of micro calorimetric sensors from millimeter- or sub-millimeter-tubes to industrial 50 mm-tubes. Both the three-element calorimetric mode and the two-element calorimetric mode were operated and calibrated on an industrial gas calibration system. It is shown that the measuring range of the prototype reaches up to 0-37.5 m³/h. Both Characteristics and optimization methods of the two calorimetric modes are discussed respectively and comparison of the two calorimetric modes is also included.