MEMS Flow Sensor Using Suspended Graphene Diaphragm With Microhole Arrays

This letter reports a miniature flow sensor using a suspended composite membrane of graphene and silicon nitride containing an array of microscale through-holes. As a fluid flow passes through these microholes, the graphene layer of the composite membrane is stressed to change its electrical resistance due to the piezoresistive effect of graphene. The creation of the microholes in graphene allows for a wide dynamic range of the sensor from 5 to 56 m/s of air flow velocity. The sensor also exhibits an air flow rate sensitivity of similar to 7 x 10(-8) (m/s)(-1).