Low pressure drop, CMOS compatible liquid flow sensor with sub ml/h resolution

Abstract

An innovative low cost packaging technique is used to confine a liquid flow to selected chip areas where integrated thermal flow meters have been fabricated by means of conventional simple post-processing steps. The packaging method is based on a plastic adapter, sealed to the chip using a thermal procedure. Direct contact between liquids and sensitive structures allowed to obtain an interesting combination of high resolution (0.2 ml/h in water) and low full scale pressure drop (5 mBar at 20 ml/h).