A Coriolis mass flow sensor structure in silicon

The first mass flow sensor in silicon based on the Coriolis force principle is presented. The basic sensor structure consists of a double-loop tube structure in silicon which can also be used for measurement of fluid density. The tube structure is excited electrostatically in a bending or torsion vibration mode. A liquid mass flow induces a Coriolis force which results in a tube twisting angular motion. The Coriolis angular motion is linearly proportional to the mass-flow and is detected optically. The measurement results show good, true mass flow direction sensitivity with high linearity in the investigated flow range below 0.5 g/s.