High-Throughput Fabrication of Sub-Micron Pillar Arrays for Free-Solution

DNA Electrophoresis without E-beam Lithography

Y. C. Chan, Y.-K. Lee, M. Wong and Y. Zohar

A new technology approach for the design, fabrication and application of an integrated free-solution electrophoresis microsystem is presented. The technology approach, which utilizes the dual-photolithography provided from a stepper and a contact aligner, allows fast and flexible formation of sub-micron pillar array patterns on a silicon substrate. Combining with standard microfabrication technique and deep-reactive-ion-etching (DRIE), very high aspect-ratio sub-micron pillar arrays can be integrated in regular microfluidic system for free-solution DNA electrophoresis. DNA interaction with pillars inside the microsystem has been demonstrated, supporting the new technology approach a novel technique for Si-based free-solution electrophoresis microsystem fabrication.

ACKNOWLEDGEMENTS

This work is supported by the Hong Kong Research Grant Council through RGC grant HKUST6017/02E.

REFERENCES

[1] D.J. Harrison, K. Fluri, K. Seiler, Z. Fan, C.S. Effenhauser & A. Manz, “Micromachining a miniaturized capillary electrophoresis-based chemical analysis

system on a chip”, Science, vol. 261, pp. 895-897, 1993.

[2] S.C. Jacobson, R. Hergenroder, L.B. Koutny, R.J. Warmack & J.M. Ramsey, “Effects of injection schemes and column geometry on the performance of

microchip electrophoresis devices”, Analytical Chemistry, vol. 66, pp. 1107-1113, 1994.

[3] Y.C. Chan, R.M.S. Ma, M. Carles, N.J. Sucher, M. Wong & Y. Zohar, “DNA kinetics in microfabricated devices”, Proceedings of the IEEE Micro

Electro Mechanical Systems (MEMS) 2002 Conference, pp. 60-63, 2002.

[4] Y.C. Chan, M. Carles, N.J. Sucher, M. Wong & Y. Zohar, “Design and fabrication of an integrated microsystem for microcapillary electrophoresis”, J.

Micromech. Microeng. vol. 13, pp. 914-921, 2003.

[5] W.D. Volkmuth & R.H. Austin, “DNA electrophoresis in microlithographic arrays”, Nature, vol. 358, pp. 600-602, 1992.

[6] S.W.P. Turner, M. Cabodi, & H.G. Craighead, “Confinement-induced entropic recoil of single DNA molecules in a nanofluidic structure”, Physical

Review Letters, vol. 88, pp. 128103/1-4, 2002.

[7] O. Bakajin, T.A.J. Duke, J. Tegenfeldt, C.F. Chou, S.S. Chan, R.H. Austin & E.C. Cox, “Separation of 100-kilobase DNA molecules in 10 seconds”,

Analytical Chemistry, vol. 73, pp. 6053-6056, 2001.

[8] N. Kaji, Y. Tezuka, Y. Takamura, M. Ueda, T. Nishimoto, H. Nakanishi, Y. Horiike & Y. Baba, “Separation of long DNA molecules by quartz

nanopillar chips under a direct current electric field”, Analytical Chemistry, vol. 76, pp. 15-22, 2004.

[9] J.L. Viovy, “Electrophoresis of DNA and other polyelectrolytes: Physical mechanisms”, Reviews of Modern Physics, vol. 72, pp. 813-872, 2000.