Design of a novel 2-D silicon piezoresistive flow sensor

Based on silicon direct bonding, SU-8 photoresist process and piezoresistive sensing, a novel 2D non-thermal flow sensor is introduced firstly where a pillar-beam structure converts the flow velocity and direction to deflection of pillar and corresponding deformation of beams. Deformation sensing is accomplished using piezoresistive strain gauges fabricated at the ends of four orthogonal beams. The velocity and direction can be determined from the change of piezoresistances. A Wheatstone bridge is used to get sinusoidal voltage output. The structure deformation of this device was given by FEA methods, and the output voltages were theoretically calculated