Abstract: During the past decade,high-throughput volume transfers of liquids in the submicroliter range have become an important feature of liquid-handling robotic instruments in protein crystallization,drug discovery and medical diagnostics.Applications requiring quickly measurement of submicroliter to nanoliter quantities flow rate to provide closed-loop control for accurately dispensing liquids with a large range of viscosities and detecting air bubbles or nozzle clogs in real time.In this paper,an integrated high-speed liquid flow sensor based on the measurement of the pressure difference across a flow restriction is presented.The micro-fluidic channel was etched on the backside of two Silicon piezo-resistive pressure sensors.Equations are derived to describe the sensor behavior both statically as well as dynamically,which is helpful for sensor dimension designing.From the dynamics analyses,a working range bandwidth of about 1 KHz is expected.The sensor’s low dead volume,high speed and accuracy allow it to control submicroliter to nanoliter liquid quantities.