0
Research Papers

Fabrication of Centimeter Long, Ultra-Low Aspect Ratio Nanochannel Networks in Borosilicate Glass Substrates

[+] Author and Article Information
Marie Pinti

e-mail: pinti.3@osu.edu

Tanuja Kambham

e-mail: kambham.1@osu.edu

Bowen Wang

e-mail: wang.3161@osu.edu

Shaurya Prakash

e-mail: prakash.31@osu.edu
Mechanical and Aerospace
Engineering Department,
The Ohio State University,
Columbus, OH 43210

1Corresponding author.

Manuscript received July 25, 2013; final manuscript received August 15, 2013; published online October 3, 2013. Assoc. Editor: Abraham Wang.

J. Nanotechnol. Eng. Med 4(2), 020905 (Oct 03, 2013) (7 pages) Paper No: NANO-13-1042; doi: 10.1115/1.4025366 History: Received July 25, 2013; Revised August 15, 2013

Nanofluidic devices have a broad range of applications resulting from the dominance of surface-fluid interactions. Examples include molecular gating, sample preconcentration, and sample injection. Manipulation of small fluid samples is ideal for micro total analysis systems or lab on chip devices which perform multiple unit operations on a single chip. In this paper, fabrication procedures for two different ultra-low aspect ratio (ULAR) channel network designs are presented. The ULAR provides increased throughput compared to higher aspect ratio features with the same critical dimensions. Channel network designs allow for integration between microscale and nanoscale fluidic networks. A modified calcium assisted glass–glass bonding procedure was developed to fabricate chemically uniform, all glass nanochannels. A polydimethylsiloxane (PDMS)-glass adhesive bonding procedure was also developed as adhesive bonding allows for more robust fabrication with lower sensitivity to surface defects. The fabrication schemes presented allow for a broad array of available parameters for facile selection of device fabrication techniques depending on desired applications for lab on chip devices.

FIGURES IN THIS ARTICLE
<>
Copyright © 2013 by ASME
Your Session has timed out. Please sign back in to continue.

References

Swaminathan, V. V., Gibson, L. R., II, Pinti, M., Prakash, S., Bohn, P. W., and Shannon, M. A., 2012, “Ionic Transport in Nanocapillary Array Membranes,” J. Nanopart. Res., 14, p. 951. [CrossRef]
Prakash, S., Piruska, A., Gatimu, E. N., Bohn, P. W., Sweedler, J. V., and Shannon, M. A., 2008, “Nanofluidics: Systems and Applications,” IEEE Sens. J., 8(5), pp. 441–450. [CrossRef]
Prakash, S., Karacor, M. B., and Banerjee, S., 2009, “Surface Modification in Microsystems and Nanosystems,” Surf. Sci. Rep., 64(7), pp. 233–254. [CrossRef]
Prakash, S., and Karacor, M. B., 2011, “Characterizing Stability of “Click” Modified Glass Surfaces to Common Microfabrication Conditions and Aqueous Electrolyte Solutions,” Nanoscale, 3(8), pp. 3309–3315. [CrossRef] [PubMed]
Shannon, M. A., 2012, “Water Desalination: Fresh for Less,” Nat. Nanotechnol., 5, pp. 248–250. [CrossRef]
Kim, S. J., Ko, S. H., Kang, K. H., and Han, J., 2010, “Direct Seawater Desalination by Ion Concentration Polarization,” Nat. Nanotechnol., 5, pp. 297–301. [CrossRef] [PubMed]
Kuo, T. C., Cannon, D. M.Jr., Chen, Y., Tulock, J. J., Shannon, M. A., Sweedler, J. V., and Bohn, P. W., 2003, “Gateable Nanofluidic Interconnects for Multilayed Microfluidic Separation Systems,” Anal. Chem., 75(8), pp. 1861–1867. [CrossRef] [PubMed]
Pardon, G., and Wijingaart, W. V. D., “Modelling and Simulation of Electrostatically Gated Nanochannels,” Adv. Colloid Interface Sci. (in press).
Goswami, P., and Chakraborty, S., 2010, “Energy Transfer through Streaming Effects in Time-Periodic Pressure-Driven Nanochannel Flows With Interfacial Slip,” Langmuir, 26(1), pp. 581–590. [CrossRef] [PubMed]
Pennathur, S., Eijkel, J. C., and Berg, A. V. D., 2007, “Energy Conversion in Microsystems: Is There a Role for Micro/Nanofluidics,” Lab Chip, 10, pp. 1234–1237. [CrossRef]
Matteucci, M., Christiansen, T. L., Tanzi, S., Ostergaard, P. F., and Larsen, S. T., 2013, “Fabrication and Characterization of Injection Molded Multi Level Nano and Microfluidic Systems,” Microelectron. Eng., 111, pp. 294–298. [CrossRef]
Yasuri, T., Rahong, S., Motoyama, K., Yanagida, T., Wu, Q., Kaji, N., Kanai, M., Doi, K., Nagashima, K., Tokeshi, M., Taniguchi, M., Kawano, S., Kawai, T., and Baba, Y., 2013, “DNA Manipulation and Separation in Sublithographic-Scale Nanowire Array,” ACS Nano, 7(4), pp. 3029–3035. [CrossRef] [PubMed]
Fu, J., Schoch, R. B., Stevens, A. L., Tannenbaum, S. R., and Han, J., 2007, “A Patterned Anisotropic Nanofluidic Sieving Structure for Continuous-Flow Separation of DNA and Proteins,” Nat. Nanotechnol., 2(2), pp. 121–128. [CrossRef] [PubMed]
Prakash, S., Pinti, M., and Bhushan, B., 2012, “Theory, Fabrication and Applications of Microfluidic and Nanofluidic Biosensors,” Philos. Trans. R. Soc. London, 370, pp. 2269–2303. [CrossRef]
Mark, D., Haeberle, S., Roth, G., Stetten, F. V., and Zengerle, R., 2012, “Microfluidic Lab-on-a-Chip Platforms: Requirements, Characteristics, and Applications,” Chem. Soc. Rev., 39, pp. 1153–1182. [CrossRef]
Kovarik, M. L., Gach, P. C., Ornoff, D. M., Wang, Y., Balowski, J., Farrag, L., and Allbritton, N. L., 2012, “Micro Total Analysis Systems for Cell Biology and Biochemical Assays,” Anal. Chem., 84, pp. 516–540. [CrossRef] [PubMed]
Rios, A., Zougagh, M., and Avila, M., 2012, “Miniaturization Through Lab-on-a-Chip: Utopia or Reality for Routine Laboratories? A Review,” Anal. Chim. Acta, 740, pp. 1–11. [CrossRef] [PubMed]
Squires, T. M., Messinger, R. J., and Manalis, S. R., 2008, “Making it Stick: Convection, Reaction and Diffusion in Surface-Based Biosensors,” Nat. Biotechnol., 26(4), pp. 417–426. [CrossRef] [PubMed]
Pinti, M., and Prakash, S., 2013, “Fabrication of Hybrid Micro-Nanofluidic Devices With Centimeter Long Ultra-Low Aspect Ratio Nanochannels,” Proceedings of ASME 2013 International Mechanical Engineering Congress and Exposition, IMECE2013_65763, November 17–21, San Diego, CA (in press).
Duan, C., Wang, W., and Xie, Q., 2013, “Fabrication of Nanofluidic Devices,” Biomicrofluidics, 7, p. 026501. [CrossRef]
Pinti, M., and Prakash, S., 2011, “A Two-Step Wet Etch Process for the Facile Fabrication of Hybrid Micro-Nanofluidic Devices,” Proceedings of ASME 2011 International Mechanical Engineering Congress and Exposition, IMECE2011_64508, November 11–17, Denver, CO, pp. 647–651.
Huang, X. T., Gupta, C., and Pennathur, S., 2010, “A Novel Fabrication Method for Centimeter-Long Surface-Micromachined Nanochannels,” J. Micromech. Microeng., 20, p. 015040. [CrossRef]
Han, A., Rooij, N. F. D., and Staufer, U., 2006, “Design and Fabrication of Nanofluidic Devices by Surface Micromachining,” Nanotechnology, 17(10), pp. 2498–2503. [CrossRef] [PubMed]
Duan, C., and Majumdar, A., 2010, “Anomalous Ion Transport in 2-nm Hydrophillic Nanochannels,” Nat. Nanotechnol., 5, pp. 848–852. [CrossRef] [PubMed]
Menard, L. D., and Ramsey, J. M., 2011, “The Fabrication of Sub-5 nm Nanochannels in Insulating Substrates Using Focused Ion Beam Milling,” Nano Lett., 11, pp. 512–517. [CrossRef] [PubMed]
Mao, P., and Han, J., 2005, “Fabrication and Characterization of 20 nm Planar Nanofluidic Channels by Glass-Glass and Glass-Silicon Bonding,” Lab Chip, 5, pp. 837–844. [CrossRef] [PubMed]
Haneveld, J., Tas, N. R., Brunets, N., Jansen, H. V., and Elwenspoek, M., 2008, “Capillary Filling of Sub-10 nm Nanochannels,” J. Appl. Phys., 104, p. 014309. [CrossRef]
Duan, C., Karnik, R., Liu, M. C., and Majumdar, A., 2012, “Evaporation-Induced Cavitation in Nanofluidic Channels,” Proc. Natl. Acad. Sci. U.S.A., 109(10), pp. 3688–3693. [CrossRef] [PubMed]
Allen, P. B., and Chiu, D. T., 2008, “Calcium-Assisted Glass-to-Glass Bonding for Fabrication of Glass Microfluidic Devices,” Anal. Chem., 80, pp. 7153–7157. [CrossRef] [PubMed]
Iliescu, C., Chen, B., and Miao, J., 2008, “On the Wet Etching of Pyrex Glass,” Sens. Actuators, A, 143, pp. 154–161. [CrossRef]
Bhattacharya, S., Datta, A., Berg, J. M., and Gangopadhyay, S., 2005, “Studies on Surface Wettability of Poly(Dimethyl) Siloxane (PDMS) and Glass Under Oxygen-Plasma Treatment and Correlation with Bond Strength,” J. Microelectromech. Syst., 14(3), pp. 590–597. [CrossRef]
Knight, R. D., 2003, Physics for Scientists and Engineers: A Strategic Approach, Addison-Wesley, San Francisco, CA.
Tay, F., Iliescu, C., Jing, J., and Miao, J., 2006, “Defect-Free Wet Etching Through Pyrex Glass Using Cr/Au Mask,” Microsyst. Technol., 12, pp. 935–939. [CrossRef]
Zhu, H., Holl, M., Ray, T., Bhushan, S., and Meldrum, D. R., 2009, “Characterization of Deep Wet Etching of Fused Silica Glass for Single Cell and Optical Sensor Deposition,” J. Micromech. Microeng., 19, p. 065013. [CrossRef]
Prakash, S., Long, T. M., Selby, J. C., Moore, J. S., and Shannon, M. A., 2007, ““Click” Modification of Silica Surfaces and Glass Microfluidic Channels,” Anal. Chem., 79(4), pp. 1661–1667. [CrossRef] [PubMed]
Yeom, J., Wu, Y., Selby, J. C., and Shannon, M. A., 2005, “Maximum Achievable Aspect Ratio in Deep Reactive Ion Etching of Silicon Due to Aspect Ratio Dependent Transport and the Microloading Effect,” J. Vac. Sci. Technol. B, 23(6), pp. 2319–2329. [CrossRef]
Yeom, J., and Shannon, M. A., 2009, “Detachment Lithography of Photosensitive Polymers: A Route to Fabricating Three-Dimensional Structures,” Adv. Funct. Mater., 20, pp. 289–295. [CrossRef]
Jackman, R. J., Wilbur, J. L., and Whitesides, G. M., 1995, “Fabrication of Submicrometer Features on Curved Substrates by Microcontact Printing,” Science, 269, pp. 664–666. [CrossRef] [PubMed]
Leong, T. G., Lester, P. A., Koh, T. L., Call, E. K., and Gracias, D. H., 2007, “Surface Tension-Driven Self-Folding Polyhedra,” Langmuir, 23, pp. 8747–8751. [CrossRef] [PubMed]
Mata, A., Fleischman, A. J., and Roy, S., 2005, “Characterization of Polydimethylsiloxane (PDMS) Properties for Biomedical Micro/Nanosystems,” Biomed. Microdevices, 7(4), pp. 281–293. [CrossRef] [PubMed]

Figures

Grahic Jump Location
Fig. 1

A schematic representation of the two fluidic network designs. Design 1 had two micron depth channels connected by a bank of nanometer depth channels. The depth of each feature was controlled by the etching time. The microchannels were 3 cm long and 131 μm ± 1 μm wide with a typical depth of 8.0 μm ± 0.1 μm. The nanochannel array consisted of 3–6 nanochannels that were 0.5 cm long and 33 μm ± 1 μm wide. The depth of the nanochannels ranged from 16.0 nm ± 0.1 nm to 227 nm ± 5 nm. Design 2 had nanoscale depth features only. The upper branch was 1 cm long and 106 μm wide. At the Y-junction the channel split into two 56 μm wide branches. Depths of the “Y” nanochannel network ranged from 77 nm ± 6 nm to 446 nm ± 5 nm.

Grahic Jump Location
Fig. 2

(a) A microscope image showing channel deformation in a 77 nm deep, 50 μm nominal width channel. (b) A microscope image showing channel deformation in a 77 nm deep, 100 μm nominal width channel fabricated without a metal mask. (c) A microscope image showing a visually uniform channel width for a 77 nm deep channel fabricated with a metal mask as marked by the white arrows.

Grahic Jump Location
Fig. 3

(a) A flow chart of channel network fabrication for Design 1. Briefly, a metal etch mask was applied to a piranha cleaned borosilicate substrate. UV lithography was used to pattern microchannel features. UV lithography with a modified spin process was used to create nanochannel pattern. (b) A schematic representation of the defect formed at the micronanochannel interface using standard UV lithography without a modified spin process. The photoresist did not fully fill the microchannel, leading to delamination at the micronanochannel interface. The nanochannels were fluidically connected by a ridge of the same depth as the nanochannels.

Grahic Jump Location
Fig. 4

SEM images of the micro-nanochannel interface of the hybrid channel network (Design 1). Figure 4(a) shows the nanoscale defect caused by photoresist delamination resulting in fluidically connected nanochannels. The ridge connecting the channels was the same depth as the channel itself [21]. Figure 4(b) shows a device fabricated using the modified spin procedure, resulting in elimination of the defect.

Grahic Jump Location
Fig. 5

An SEM image of a 227 nm deep 33 μm wide nanochannel bonded using a 2 μm thick PDMS adhesive layer [19]. The inset shows a zoomed in image of the channel cross section.

Grahic Jump Location
Fig. 6

A plot of measured current as a function of applied voltage for a 22 nm PDMS-glass device. A linear trend was observed suggesting that the in the voltage range tested the nanochannel permits ions to move across and is evidence for electrokinetic transport through nanochannels.

Grahic Jump Location
Fig. 7

A cross section image of a 56 μm wide and 77 nm deep nanofluidic channel bonded using calcium assisted bonding. The channel height varies at different points in the channel from 62 to 77 nm, presumably due to cutting the nanochannels for imaging [28].

Grahic Jump Location
Fig. 8

Microscope images of nanochannels of various depths filling with isopropyl alcohol in a capillary fill. Lines denoting the channel walls have been added to the image of the 77 nm deep channel for visual clarity.

Tables

Errata

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related Journal Articles
Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In