Micromachined silicon cantilever paddles with piezoresistive readout for flow sensing

A group of piezoresistive silicon cantilever paddles have been fabricated, each of which consists of a paddle square which is attached by two cantilever arms, and a piezoresistive sensor on the root surface of each arm. The process involves a combination of wet and dry etching techniques. The fabricated cantilever paddles are 200-550 mu m long and 25-40 mu m wide with a paddle square of 100-250 mu m. The measured sensitivity (Delta R/R/y(0)) of the cantilever devices is 0.23-2.91 x 10(-6) nm(-1), which is in good agreement with the values predicted by our derived formula. These cantilever paddles have potential application in flow sensors.