Micropump fabricated with LIGA process

Summary form only given. A prototype micropump made of a gold structure 100 μm in height, covered by a titanium membrane on one side and a glass plate on the other, is reported. The titanium membrane is 2.7-μm thick and deflects to near the bottom of the pump chamber (100 μm) under a pressure of 500 hPa. Pump chambers with diameters of 2 to 5 mm have been fabricated with volumes from 0.3 μl to 2 μl. To fabricate the pump, a low-adhesive carbon layer was deposited onto a silicon wafer and covered by a titanium layer. Openings in the titanium were patterned by photolithography and etching. On top of these openings perforated polyimide membranes were built up, forming inlet valves on the titanium layer. Then, the gold structure, aligned relative to the microvalves, was fabricated with the LIGA process. The microstructure was closed with a glass plate