Development of LIGA-fabricated, self-priming, in-line gear pumps

This paper reports the development and characterization of the self-priming, magnetically-actuated, two-gear plastic pump which is fabricated by the sacrificial LIGA process. This positive displacement, in-line pump provides a flow rate of 350 μl/min at 5000 rpm, over 140 cm-H₂O (~2 psi) of head pressure and 28.8 cm-H₂O vacuum on the suction side for a single stage pump. It is the first non-diaphragm, microfabricated pump. A two stage in-line pump generated 533 mm-H₂O vacuum at its inlet (21" H₂O). This performance demonstrates a viable, microfabricated alternative to syringe pumps and compressed gas for moving fluids in micro-instrumentation