Title:A Thermal Microfluidic Flow Sensor Screen-Printed onto an Ultrathin PMMA FoilAuthor(s):Rafael Ecker, Tina Mitteramskogler, Bernhard JakobyAbstract:This paper reports on the devised fabrication procedure and experimental investigation and characterization of a thermal based flow sensor for microfluidic systems based on polymer technology. The sensor itself is screen-printed onto a self-fabricated ultrathin polymethylmethacrylate (PMMA) foil, which minimizes the heat capacity and therefore yields fast response times of integrated thermal transducers. Integrating the foil-based sensor into the center of a PMMA stack consisting of a substrate and a top plate (both preprocessed to form a microfluidic channel) enables a suitable material compatibility and a low-cost fabrication procedure. Using the well-known evaluation principles of thermal anemometers, the four-wire sensor can be used for accurate flow measurements in such polymer-based microfluidic systems, where the measurement range of the sensor is easily adaptable by changing the channel's height. Currently, it is possible to measure flows starting in the range of 10 μl per minute up to 1000 μl per minute.Booktitle:2023 IEEE SENSORSPublisher:IEEEPage Reference:page 1-4, 4 page(s)Publishing:11/2023