Flexible MEMS flow sensor based on double-helix heater
To overcome the range limitation of traditional flow sensors,a flexible substrate MEMS thermal flow sensor based on double helix structure heater is proposed.To reduce the heat conduction loss,an uniform through-hole array is made on the substrate.Two pairs of temperature measurement resistors are symmetrically distributed on both sides of the heater,resulting in a wide range and high sensitivity at both small and large flow.The output voltage is measured using a detection circuit based on Wheatstone bridge,at the same time,maintain a constant temperature difference of 200 K between the heater and the ambient temperature to compensate for the self-heating of the resistor.The operating temperature of the sensor is-100～400℃,and the range is 0～60 m/s.The sensitivity is about 12.75 V/(m·s-1)at low flow rates with a resolution of 0.001 mm/s,the sensitivity is about 1.4 mV/(m·s-1)at a high flow rate.The power consumption is as low as 1.3 mW.
MEMSheat flow sensordouble helix structurethermal temperature difference typeflexible
万方数据
维普
