Abstract
An experimental study has been carried out to estimate the heat transfer improvement offered by a novel electro-osmotic (EO) heat spreader for microprocessor cooling. The proposed design of the elliptical silicon heat spreader can be fabricated at the back surface of the microprocessor as an integral part. Thus, no extra space may be required. The EO heat spreader developed is 0.6 mm3 in volume and it contains a pair of thin gold film electrodes of approximately 1 μm thickness for applying an external electric field that induces electro-osmotic flow. The inner channel surfaces of the heat spreader are electrically insulated with a thin SiO2 layer to minimize current leakage into the wafer. The EO heat spreader constructed is able to generate a flow rate of 0.2028 μl/min at 2 V/mm. With this heat spreader, the temperature of a heat source may be reduced by up to 4°C without the aid of any external mechanical devices. The heat spreader has the potential to make the temperature uniform, if the heat source is non-uniform in nature.
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This work was partially funded by EPSRC grant D070554.
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Eng, P.F., Nithiarasu, P. & Guy, O.J. An experimental study on an electro-osmotic flow-based silicon heat spreader. Microfluid Nanofluid 9, 787–795 (2010). https://doi.org/10.1007/s10404-010-0594-3
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DOI: https://doi.org/10.1007/s10404-010-0594-3