Manipulation of Microfluid Width in a Microchannel Using Gas Boundary

미세 채널에서 가스 경계면을 이용한 미세 유체의 폭 조절

  • 손상욱 (한국과학기술원 기계공학과) ;
  • 이승섭 (한국과학기술원 기계공학과)
  • Published : 2004.08.01


A novel manipulation of microfluid width in a microchannel was presented by controlling inflation of a gas boundary. The gas boundary was formed by heating water with a microheater in a semicircular shape from a chamber which was connected symmetrically to the microchannel. The formed gas boundary inflated perpendicularly to the flow direction and, consequently, the microfluid width was narrowed. The inflation and contraction were flexibly like a virtual wall and dependent on two factors: one is the flow velocity of the microfluid and the other is the pressure inside the gas boundary. Dimensions of the chamber and the microchannel width were determined empirically as same of $300\;{\mu}m$ for stable operation. The width of microfluid was manipulated manually with the microheater and could be maintained as up to $22\;{\mu}m$. The stable focusing began to be distorted when the flow velocity exceeded 17.8 mm/s.


  1. Arash Dodge, Gijs W. K. van Dedem, Nico F. de Rooij, and Elisabeth Verpoorte, 2003, 'Chemical and Physical Processes for Integrated Temperature Control in Microfluidic Devices,' Lab on a chip, Vol. 3, pp. 1-4
  2. Yasuda, K. Umemura, S. -I. and takeda, K., 1995, 'Concentration and Fractionation of Small Particles in Liquid by Ultrasound,' Jpn. J. Appl. Phys., Vol. 34, pp. 2715-2720
  3. Belhardj, S., Mimouni, S., Saidane, A. and Benzohra, M., 2003, 'Using Microchannels to Cool Microprocessors: a Transmission-Line-Matrix Study,' Micro-Electronics J., Vol. 34, pp. 247-253
  4. Nieuwenhuis, J. H., Bastemeijer, J., Sarro, P. M. and Vellekoop, M. J., 2003, 'Integrated Flow-Cells for Novel Adjustable Sheath Flows,' Lab on a chip, Vol. 3, pp. 56-61
  5. Deval, J., Tabeling, P., Ho, C. -M. Ho, 2002, 'A Dielectrophoretic Chaotic Mixer,' Proc. IEEE Int. Conf. On Micro Electro Mechanical Systems (MEMS'02), pp. 36-39
  6. Lee, Y.-K., Deval, J., Tabeling, P. and Ho, C.-M., 2001, 'Chaotic Mixing in Electrokinetically and Pressure Driven Micro Flows,' MEMS 2001, Interlaken, Switzerland, January 21-25, pp. 483-486
  7. Branebjerg, J., Gravesen, P. and Krog, J.P., 1996, 'Fast Mixing by Lamination,' MEMS 96, San Diego, CA, February 11-15, pp. 441-446
  8. James B. Knight, Ashbin Vishwanath, James P. Brody and Robert H. Austin, 1998, 'Hydrodynamic Focusing on a Silicon Chip: Mixing Nanoliters in Microseconds,' Physical Review Letters, Vol. 80, No. 17, pp. 3863-3866
  9. Miyake R., Ohki H., Yamazaki I., Yabe R., 1991, 'A Development of Micro Sheath Flow Chamber,' Proc. IEEE Int. Conf. On Micro Electro Mechanical Systems (MEMS'91), pp. 265-270
  10. Xie, J., He, Q., Tai, Y. -C., Liu, J. and Lee, T., 2002, 'Integrated Electrospray Chip for Mass Spectrometry,' Proc. Int. Conf. On Micro Total Analysis Systems $({\mu}TAS'02),$ pp. 709-711
  11. Yo Han Choi, Sanguk Son and Seung S. Lee, 2003, 'Novel Micropump Using Oxygen as Pumping Source,' Proceedings of the 16th IEEE MEMS conference, pp. 116-119
  12. Chien-Chong Hong, Suresh Murugesan, Sanghyo Kim, Gregory Beaucage, Jin-Woo Choi and Chong H. Ahn, 2003, 'A Functional On-chip Pressure Generator Using Solid Chemical Propellant for Disposable Lab-on-a-chip,' Proceedings of the 16th IEEE MEMS conference, pp. 16-19
  13. Son, S. U., Choi, Y. H. and Lee, S. S. 2003, 'Fabrication of Micro Cell Counter Integrated with Oxygen Pump,' Proc. Korean MEMS Conf., pp. 436-440
  14. Liu, R. H., Yang, J., Pindera, M. Z., Athavale, M. and Grodzinski, P., 2002, 'Bubble-Induced Acoustic Micromixing,' Lab on a chip, Vol. 2, pp. 151-157
  15. Chang, R., 1981, 'Chemistry,' 2nd ed., Random House, New York, p. 63, p. 591