Research Papers

Improved Flow Rate in Electro-Osmotic Micropumps for Combinations of Substrates and Different Liquids With and Without Nanoparticles

[+] Author and Article Information
Marwan F. Al-Rjoub

School of Dynamic Systems,
University of Cincinnati,
598 Rhodes Hall,
Cincinnati, OH 45221
e-mail: alrjoumf@mail.uc.edu

Ajit K. Roy

Air Force Research Laboratory,
Nanoelectronic Materials Branch,
Materials and Manufacturing Directorate,
2941 Hobson Way,
WPAFB, OH 45433-7750
e-mail: ajit.roy@wpafb.af.mil

Sabyasachi Ganguli

Air Force Research Laboratory,
Nanoelectronic Materials Branch,
Materials and Manufacturing Directorate,
2941 Hobson Way,
WPAFB, OH 45433-7750
e-mail: sabyasachi.ganguli.2@us.af.mil

Rupak K. Banerjee

Fellow ASME
School of Dynamic Systems,
University of Cincinnati,
593 Rhodes Hall,
Cincinnati, OH 45221
e-mail: rupak.banerjee@uc.edu

1Corresponding author.

Contributed by the Electronic and Photonic Packaging Division of ASME for publication in the JOURNAL OF ELECTRONIC PACKAGING. Manuscript received June 17, 2014; final manuscript received September 19, 2014; published online November 17, 2014. Assoc. Editor: Yi-Shao Lai.

This work is in part a work of the U.S. Government. ASME disclaims all interest in the U.S. Government's contributions.

J. Electron. Packag 137(2), 021001 (Jun 01, 2015) (11 pages) Paper No: EP-14-1059; doi: 10.1115/1.4028746 History: Received June 17, 2014; Revised September 19, 2014; Online November 17, 2014

A new design for an electro-osmotic flow (EOF) driven micropump was fabricated. Considering thermal management applications, three different types of micropumps were tested using multiple liquids. The micropumps were fabricated from a combination of materials, which included: silicon-polydimethylsiloxane (Si-PDMS), Glass-PDMS, or PDMS-PDMS. The flow rates of the micropumps were experimentally and numerically assessed. Different combinations of materials and liquids resulted in variable values of zeta-potential. The ranges of zeta-potential for Si-PDMS, Glass-PDMS, and PDMS-PDMS were −42.5–−50.7 mV, −76.0–−88.2 mV, and −76.0–−103.0 mV, respectively. The flow rates of the micropumps were proportional to their zeta-potential values. In particular, flow rate values were found to be linearly proportional to the applied voltages below 500 V. A maximum flow rate of 75.9 μL/min was achieved for the Glass-PDMS micropump at 1 kV. At higher voltages nonlinearity and reduction in flow rate occurred due to Joule heating and the axial electro-osmotic current leakage through the silicon substrate. The fabricated micropumps could deliver flow rates, which were orders of magnitude higher compared to the previously reported values for similar size micropumps. It is expected that such an increase in flow rate, particularly in the case of the Si-PDMS micropump, would lead to enhanced heat transfer for microchip cooling applications as well as for applications involving micrototal analysis systems (μTAS).

Copyright © 2014 by ASME
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Probstein, R., 1994, Physicochemical Hydrodynamics: An Introduction, Wiley, Hoboken, NJ, Chap. VI.
Iverson, B. D., and Garimella, S. V., 2008, “Recent Advances in Microscale Pumping Technologies: A Review and Evaluation,” Microfluid. Nanofluid., 5(2), pp. 145–174. [CrossRef]
Chen, C., and Santiago, J., 2002, “A Planar Electroosmotic Micropump,” J. Microelectromech. Syst., 11(6), pp. 672–683. [CrossRef]
Chujo, H., Matsumoto, K., and Shimoyama, I., 2003, “A High Flow Rate Electro-Osmotic Pump With Small Channels in Parallel,” IEEE 16th Annual International Conference on Micro Electro Mechanical Systems (MEMS-03), Kyoto, Japan, Jan. 19–23, pp. 351–354. [CrossRef]
Chen, L., Wang, H., Ma, J., Wang, C., and Guan, Y., 2005, “Fabrication and Characterization of a Multi-Stage Electroosmotic Pump for Liquid Delivery,” Sens. Actuators, B, 104(1), pp. 117–123. [CrossRef]
Seibel, K., Schöler, L., Schäfer, H., and Böhm, M., 2008, “A Programmable Planar Electroosmotic Micropump for Lab-on-a-Chip Applications,” J. Micromech. Microeng., 18(2), p. 025008. [CrossRef]
Zeng, S., Chen, C. H., Mikkelsen, J. C., and Santiago, J. G., 2001, “Fabrication and Characterization of Electroosmotic Micropumps,” Sens. Actuators, B, 79(2–3), pp. 107–114. [CrossRef]
Takamura, Y., Onoda, H., Inokuchi, H., Adachi, S., Oki, A., and Horiike, Y., 2003, “Low‐Voltage Electroosmosis Pump for Stand‐Alone Microfluidics Devices,” Electrophoresis, 24(1–2), pp. 185–192. [CrossRef] [PubMed]
Jahanshahi, A., Axisa, F., and Vanfleteren, J., 2012, “Fabrication of a Biocompatible Flexible Electroosmosis Micropump,” Microfluid. Nanofluid., 12(5), pp. 771–777. [CrossRef]
Harms, T., Kazmierczak, M., and Gerner, F., 1999, “Developing Convective Heat Transfer in Deep Rectangular Microchannels,” Int. J. Heat Fluid Flow, 20(2), pp. 149–157. [CrossRef]
Al-Rjoub, M. F., Roy, A. K., Ganguli, S., and Banerjee, R. K., 2011, “Assessment of an Active-Cooling Micro-Channel Heat Sink Device, Using Electro-Osmotic Flow,” Int. J. Heat Mass Transfer, 54(21), pp. 4560–4569. [CrossRef]
Laser, D. J., Myers, A. M., Yao, S. H., Bell, K. F., Goodson, K. E., Santiago, J. G., and Kenny, T. W., 2003, “Silicon Electroosmotic Micropumps for Integrated Circuit Thermal Management,” 12th International Conference on Solid State Sensors, Actuators and Microsystem, Boston, MA, June 8–12, Vol. 1, pp. 151–154.
Jung, J. Y., Oh, H. S., and Kwak, H. Y., 2009, “Forced Convective Heat Transfer of Nanofluids in Microchannels,” Int. J. Heat Mass Transfer, 52(1), pp. 466–472. [CrossRef]
Eng, P., Nithiarasu, P., and Guy, O., 2010, “An Experimental Study on an Electro-Osmotic Flow-Based Silicon Heat Spreader,” Microfluid. Nanofluid., 9(4–5), pp. 787–795. [CrossRef]
Zhang, L., Koo, J. M., Jiang, L., Asheghi, M., Goodson, K. E., Santiago, J. G., and Kenny, T. W., 2002, “Measurements and Modeling of Two-Phase Flow in Microchannels With Nearly Constant Heat Flux Boundary Conditions,” J. Microelectromech. Syst., 11(1), pp. 12–19. [CrossRef]
Sze, A., Erickson, D., Ren, L. Q., and Li, D. Q., 2003, “Zeta-Potential Measurement Using the Smoluchowski Equation and the Slope of the Current-Time Relationship in Electroosmotic Flow,” J. Colloid Interface Sci., 261(2), pp. 402–410. [CrossRef] [PubMed]
Jiang, L. N., Mikkelsen, J., Koo, J. M., Huber, D., Yao, S. H., Zhang, L., Zhou, P., Maveety, J. G., Prasher, R., Santiago, J. G., Kenny, T. W., and Goodson, K. E., 2002, “Closed-Loop Electroosmotic Microchannel Cooling System for VLSI Circuits,” IEEE Trans. Comp. Packag. Technol., 25(3), pp. 347–355. [CrossRef]
ESI, 2006, “CFD-ACE+ User Manual V2006,” ESI Group, Huntsville, AL.
ASTM, 1983, “Standard Specification for Reagent Water,” ASTM International, West Conshohocken, PA, Standard No. D1193-1977.
Dasgupta, S., Bhagat, A. A. S., Horner, M., Papautsky, I., and Banerjee, R. K., 2008, “Effects of Applied Electric Field and Microchannel Wetted Perimeter on Electroosmotic Velocity,” Microfluid. Nanofluid., 5(2), pp. 185–192. [CrossRef]
Comandur, K., Bhagat, A., Dasgupta, S., Papautsky, I., and Banerjee, R., 2010, “Transport and Reaction of Nanoliter Samples in a Microfluidic Reactor Using Electro-Osmotic Flow,” J. Micromech. Microeng., 20(3), p. 035017. [CrossRef]
Bousse, L., Mostarshed, S., Van Der Shoot, B., De Rooij, N., Gimmel, P., and Göpel, W., 1991, “Zeta Potential Measurements of Ta2O5 and SiO2 Thin Films,” J. Colloid Interface Sci., 147(1), pp. 22–32. [CrossRef]
Prakash, P., Grissom, M. D., Rahn, C. D., and Zydney, A. L., 2006, “Development of an Electroosmotic Pump for High Performance Actuation,” J. Membr. Sci., 286(1), pp. 153–160. [CrossRef]
Yao, S., Myers, A. M., Posner, J. D., Rose, K. A., and Santiago, J. G., 2006, “Electroosmotic Pumps Fabricated From Porous Silicon Membranes,” J. Microelectromech. Syst., 15(3), pp. 717–728. [CrossRef]
Moffat, R., 1988, “Describing the Uncertainties in Experimental Results,” Exp. Therm. Fluid Sci., 1(1), pp. 3–17. [CrossRef]
Kline, S., and McClintock, F., 1953, “Describing Uncertainties in Single-Sample Experiments,” Mech. Eng., 75(1), pp. 3–8.


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Fig. 1

Schematics of the micropump showing the major components; the PDMS-cast microchannels and the Si substrate

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Fig. 2

Fabrication processes of the PDMS cover (not to scale)

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Fig. 3

ESEM photographs showing the PDMS cover (80×) and a single microchannel wall (500×)

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Fig. 4

(a) Schematics of the experimental flow loop and (b) photograph of the experimental flow loop

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Fig. 5

Experimental setup used to evaluate the P–Q curve of the micropump

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Fig. 6

Fluid flow rates at different voltages for DS water, DI water, 1% Al2O3, and 0.4 mM borax buffer (showing R2 values for two voltage ranges 100–500 V and 100–800 V)

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Fig. 7

Pressure–flow (P–Q) curves for the Si-PDMS micropump using: (a) DI water, (b) DS water, (c) 0.4 mM borax buffer, and (d) 1% Al2O3 nanoparticle solution

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Fig. 8

Fluid flow rates at different voltages for Si-PDMS, Glass-PDMS, and PDMS-PDMS, using DS water

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Fig. 9

Experimental and numerical flow rates for: (a) Si-PDMS section, (b) Glass-PDMS section, and (c) PDMS-PDMS section

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Fig. 10

ESEM photographs of silicon etched microchannels used in earlier designs. (a) Wet etched channels, (b) wet etched channel walls, and (c) dry etched channels.

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Fig. 11

Magnitude of Joule heating in (W) for all liquids at different EOF voltages




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