On the co-integration of a thermo-resistive flow-rate sensor in a multi-parameter sensing chip for water network monitoring

Motivated by the need for a multi-parameter sensing chip for water networks monitoring, we address here the specific case of a flow-rate sensor where the main challenge is the substrate material. Instead of using conventional low thermal conductivity materials such as glass, silicon has to be used. Indeed, a silicon substrate enables the co-integration of various kinds of sensors on the same chip as reported in this contribution. However, it increases the flow-rate sensor power consumption due to larger thermal leaks. We therefore design and study an optimized low power micro-machined thermal flow-rate sensor based on a silicon substrate and operating according to hot-wire anemometry. It can be considered as an alternative to other well established sensors for liquid flow-rate measurement when both the use of a silicon substrate and a low power consumption are needed.