Miniaturisierung hochsensitiver, hitzdrahtbasierter Massenflusssensoren mit Hilfe von Halbleiterfertigungstechnologie

We developed a highly sensitive fully integrated mass flow sensor by combining the superior operation principle and sensitivity of conventional, freely suspended macroscopic hot-wire anemometers with the advantages of miniaturized, integrated silicon sensors. This increases the measurement precision tremendously while, at the same time, covering an extremely large measurement range from several µl/min up to several ml/min. The novel concept distinguishes itself by the assembly of thermo-resistive microstructures, suspended above a through-hole processed through the cross section of the silicon chip, which minimizes thermal leakage from the sensing elements into the substrate, maximizes the thermal coupling to the fluid, and, thus, yields an at least twofold increase in measurement resolution compared to state-of-the-art industrial solutions. Manufactured in standard semiconductor technology, it is ready for cost-effective mass-production.