A novel micromachined pump based on thick-film piezoelectric actuation

Abstract

A new silicon-based micropump is described in this paper. The key element of the device is a thick-film/silicon micromachined hybrid actuator. The actuation principle relies on the flexure of a screen printed piezoelectric lead zirconate titanate (PZT) layer on a silicon membrane (8 mm/spl times/4 mm/spl times/70 /spl mu/m). Inlet and outlet valves are of the cantilever type and use deep boron diffusion together with KOH etching. Pump rates of up to 120 /spl mu/I min/sup -1/ have been achieved. A maximum backpressure of 2 kPa was measured when using a 600 V/sub pp/ sinusoidal drive voltage at 200 Hz across a 100 /spl mu/m thick PZT layer.