Aeromems Wall Hot-Wire Sensor Arrays on Polyimide with Through Foil Vias and Bottom Side Electrical Contacts

Design and manufacturing of linear arrays consisting of forty MEMS wall-hot wires on a flexible substrate featuring through foil vias and bottom side electrical contacts are presented. Realization of through foil contacts featuring a resistance of less than 0.1 Ω is based on a specifically developed process consisting of laser-"drilling" and sputtering, which is presented in detail. Measurements conducted on a flat plate in a wind tunnel demonstrate the sophistication of the system as sensor induced flow disturbances can not be detected. The sensor system presented therefore is an ideal tool to investigate sensitive flow phenomena like transition and separation.