Micro-fabricated electrokinetic pump
View Patent ↗An electrokinetic pump for pumping a liquid includes a pumping body having a plurality of narrow, short and straight pore apertures for channeling the liquid through the body. A pair of electrodes for applying a voltage differential are formed on opposing surfaces of the pumping body at opposite ends of the pore apertures. The pumping body is formed on a support structure to maintain a mechanical integrity of the pumping body. The pump can be fabricated using conventional semiconductor processing steps. The pores are preferably formed using plasma etching. The structure is oxidized to insulate the structure and also narrow the pores. A support structure is formed by etching a substrate and removing an interface oxide layer. Electrodes are formed to apply a voltage potential across the pumping body. Another method of fabricating an electrokinetic pump includes providing etch stop alignment marks so that the etch step self-terminates.
1. An electrokinetic pump for pumping a liquid comprising:
a. a body having a predetermined thickness, the body including a first outer surface and a second outer surface, wherein the first and second outer surfaces include a thin film of oxide insulation;
b. a plurality of pore apertures for channeling the liquid through the body, wherein each pore aperture extends from the first outer surface to the second outer surface and includes the thin film of oxide insulation within; and
c. a pair of electrodes for applying a voltage differential between the first outer surface and the second outer surface, wherein the voltage differential drives the liquid through the each of the pore apertures.
2. The electrokinetic pump according to claim 1 further comprising a support element coupled to the body, wherein the support element includes a plurality of support structures.
3. A cooling system loop for cooling a heat emitting device with a liquid, wherein the heat emitting device outputs the liquid having a first temperature, the cooling system comprising:
a. a microchannel heat exchanger for cooling the liquid from the heat emitting device at the first temperature to a second temperature, wherein the microchannel heat exchanger outputs the liquid at the second temperature; and
b. an electrokinetic pump for osmotically pumping the liquid output from the microchannel heat exchanger to the heat emitting device, wherein the liquid pumped to the heat emitting device is substantially at the second temperature, the electrokinetic pump further comprising:
i. a body having a predetermined thickness, the body including a first outer surface and a second outer surface, wherein the first and second outer surfaces include a thin film of oxide insulation;
ii. a plurality of pore apertures for channeling the liquid through the body, wherein each pore aperture extends from the first outer surface to the second outer surface and includes the thin film of oxide insulation within; and
iii. a pair of electrodes for applying a voltage differential between the first outer surface and the second outer surface, wherein the voltage differential drives the liquid through the each of the pore apertures.
4. The cooling system loop according to claim 3 wherein the electrokinetic pump further comprises a support element coupled to the body, wherein the support element includes a plurality of support structures.