Conference Paper

Micromachined porous polymer for bubble free electro-osmotic pump

Dept. of Electr. Eng. & Comput. Sci., Michigan Univ., Ann Arbor, MI
DOI: 10.1109/MEMSYS.2002.984050 Conference: Micro Electro Mechanical Systems, 2002. The Fifteenth IEEE International Conference on
Source: IEEE Xplore

ABSTRACT A novel porous polymer was microfabricated to serve as a porous
plug for a new device, the porous plug electro-osmotic pump (pp-EOP).
The plug eliminates any back pressure effects while enhances
electro-osmotic flow in a channel. The pp-EOP was batch fabricated by
surface micromachining on top of a silicon wafer. The pp-EOP device is
driven by a periodic, zero-average injected current signal at low
frequencies producing bubble-free electro-osmotic flow with reversible
net movement. Testing of the device produced an average water-air
interface velocity of 1.8 μm/s at 0.8 Hz. The velocity was increased
to 4.8 and to 13.9 μm/s by necking the channel size

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