Institute of Physics Publishing Journal of Micromechanics and Microengineering Polymer Embossing Tools for Rapid Prototyping of Plastic Microfluidic Devices

In this paper, we describe a simple and rapid method of fabricating hot embossing tools using polydimethylsiloxane (PDMS), which are then used to rapidly fabricate microchannels in polymethylmethacrylate (PMMA). A negative photoepoxy SU-8 or thick positive photoresist AZ4620 on silicon was used for molding during PDMS casting. Fabrication time of these PDMS tools was considerably less than those using conventional techniques and remains the same regardless of the aspect ratio of features. The described approach was used to emboss microchannels in PMMA of aspect ratios up to 2, with depths from 5 to 250 µm and widths over 40 µm. The technique was also applied to fabricating orthogonal 3D microchannels using multiple lithography steps. The use of a soft tool material increased cycle time and limited the tool lifetime to approximately 20 cycles. Our successful demonstration of PDMS embossing tools presents an alternative approach for rapidly prototyping microfluidic biochips when fast processing and low cost are important and the number of samples is relatively low.

[1]  Holger Becker,et al.  Microfluidic devices for μ-TAS applications fabricated by polymer hot embossing , 1998, Photonics West - Micro and Nano Fabricated Electromechanical and Optical Components.

[2]  Suzanne Berry,et al.  Honey I've shrunk biomedical technology! , 2002, Trends in biotechnology.

[3]  W. Stryjewski,et al.  Single molecule detection of double‐stranded DNA in poly(methylmethacrylate) and polycarbonate microfluidic devices , 2001, Electrophoresis.

[4]  Jian Zhang,et al.  Characterization of the polymerization of SU-8 photoresist and its applications in micro-electro-mechanical systems (MEMS) , 2001 .

[5]  Harold G. Craighead,et al.  Entropic trapping and sieving of long DNA molecules in a nanofluidic channel , 1999 .

[6]  G. Kovacs.  Micromachined Transducers Sourcebook , 1998 .

[7]  E. Delamarche,et al.  Patterned delivery of immunoglobulins to surfaces using microfluidic networks. , 1997, Science.

[8]  P. Dario,et al.  Micro-systems in biomedical applications , 2000 .

[9]  Hiroaki Nakanishi,et al.  Fabrication of electrophoresis devices on quartz and glass substrates using a bonding with HF solution , 1997, Proceedings IEEE The Tenth Annual International Workshop on Micro Electro Mechanical Systems. An Investigation of Micro Structures, Sensors, Actuators, Machines and Robots.

[10]  T. Rohr,et al.  Porous polymer monoliths: Simple and efficient mixers prepared by direct polymerization in the channels of microfluidic chips , 2001, Electrophoresis.

[11]  V. Piotter,et al.  Injection molding and related techniques for fabrication of microstructures , 1997 .

[12]  A. B. Frazier,et al.  A low temperature IC compatible process for fabricating surface micromachined metallic microchannels , 1997, Proceedings IEEE The Tenth Annual International Workshop on Micro Electro Mechanical Systems. An Investigation of Micro Structures, Sensors, Actuators, Machines and Robots.

[13]  M. Brunet,et al.  Advanced photoresist technologies for microsystems , 2001 .

[14]  P. Hannaford,et al.  High aspect-ratio micromachining of polymers with an ultrafast laser , 2002 .

[15]  Jack W. Judy,et al.  Microelectromechanical systems (MEMS): fabrication, design and applications , 2001 .

[16]  G. Whitesides,et al.  Rapid Prototyping of Microfluidic Systems in Poly(dimethylsiloxane). , 1998, Analytical chemistry.

[17]  G. Darby.  Physical and Chemical Constants , 1920, Nature.

[18]  Holger Becker,et al.  Hot embossing as a method for the fabrication of polymer high aspect ratio structures , 2000 .

[19]  Zhili Huang,et al.  A method for UV‐bonding in the fabrication of glass electrophoretic microchips , 2001, Electrophoresis.

[20]  Yong-Kweon Kim,et al.  In situ measurement of residual stress in micromachined thin films using a specimen with composite-layered cantilevers , 2000 .

[21]  Jin-Woo Choi,et al.  Fixed-volume metering microdispenser module. , 2002, Lab on a chip.

[22]  Ian Papautsky,et al.  Hollow Metallic Micromachined Needle Arrays , 2000 .

[23]  Liwei Lin,et al.  Silicon-processed plastic micropyramids for brightness enhancement applications , 2000 .

[24]  David Juncker,et al.  Soft and rigid two-level microfluidic networks for patterning surfaces , 2001 .

[25]  E. Y. B. Pun,et al.  Exposure characteristics and three-dimensional profiling of SU8C resist using electron beam lithography , 2001 .

[26]  Oliver Geschke,et al.  CO(2)-laser micromachining and back-end processing for rapid production of PMMA-based microfluidic systems. , 2002, Lab on a chip.

[27]  K. R. Williams,et al.  Novel interconnection technologies for integrated microfluidic systems , 1998 .

[28]  C. Gärtner,et al.  Polymer microfabrication technologies , 2002 .

[29]  Bernd Loechel.  Thick-layer resists for surface micromachining , 2000 .

[30]  M. A. Northrup,et al.  A Mems-based Miniature DNA Analysis System , 1995, Proceedings of the International Solid-State Sensors and Actuators Conference - TRANSDUCERS '95.

[31]  Chang Liu,et al.  Re-configurable fluid circuits by PDMS elastomer micromachining , 1999, Technical Digest. IEEE International MEMS 99 Conference. Twelfth IEEE International Conference on Micro Electro Mechanical Systems (Cat. No.99CH36291).

[32]  Holger Becker,et al.  Fabrication of polymer high-aspect-ratio structures with hot embossing for microfluidic applications , 1999, MOEMS-MEMS.

[33]  M. Despont,et al.  SU-8: a low-cost negative resist for MEMS , 1997 .

[34]  Richard J. Colton,et al.  Hybrid macro–micro fluidics system for a chip-based biosensor , 2002 .

[35]  J. Rossier,et al.  UV Laser Machined Polymer Substrates for the Development of Microdiagnostic Systems. , 1997, Analytical chemistry.

[36]  G. Whitesides,et al.  Rapid prototyping of microfluidic switches in poly(dimethyl siloxane) and their actuation by electro-osmotic flow , 1999 .

[37]  Ian Papautsky,et al.  A low-temperature IC-compatible process for fabricating surface-micromachined metallic microchannels , 1998 .

[38]  Richard A. Mathies,et al.  Microfabrication Technology for the Production of Capillary Array Electrophoresis Chips , 1998 .

[39]  C Gärtner,et al.  Polymer microfabrication methods for microfluidic analytical applications , 2000, Electrophoresis.

[40]  E. S. Kolesar,et al.  Silicon-micromachined gas chromatography system used to separate and detect ammonia and nitrogen dioxide. I. Design, fabrication, and integration of the gas chromatography system , 1994 .

[41]  A. Manz,et al.  Design of an open-tubular column liquid chromatograph using silicon chip technology , 1990 .

[42]  F. Watt,et al.  Micromachining using focused high energy ion beams: Deep Ion Beam Lithography , 1999 .

[43]  G. Whitesides,et al.  Components for integrated poly(dimethylsiloxane) microfluidic systems , 2002, Electrophoresis.

[44]  A. Manz,et al.  Integration Of A Micro Liquid Chromatograph Onto A Silicon Chip , 1995, Proceedings of the International Solid-State Sensors and Actuators Conference - TRANSDUCERS '95.

[45]  Shaochen Chen,et al.  Fabrication of Biodegradable Polymeric Micro-Devices Using Laser Micromachining , 2002 .

[46]  P. Dario,et al.  Non-traditional technologies for microfabrication , 1995 .

[47]  L J Kricka,et al.  Manipulation and flow of biological fluids in straight channels micromachined in silicon. , 1994, Clinical chemistry.

[48]  Swomitra K. Mohanty,et al.  Rapid micromold tooling for injection molding microfluidic components , 2002 .

[49]  A. Manz,et al.  Glass chips for high-speed capillary electrophoresis separations with submicrometer plate heights , 1993 .

[50]  S. Clark,et al.  High-speed parallel separation of DNA restriction fragments using capillary array electrophoresis. , 1993, Analytical biochemistry.

[51]  Effects of direct and pulse current on copper electrodeposition through photoresist molds , 2000 .

[52]  G. W. C. Kaye,et al.  Tables of Physical and Chemical Constants , 2018 .

[53]  R. Ghodssi,et al.  Microfluidic systems with on-line UV detection fabricated in photodefinable epoxy , 2001 .

[54]  S. Terry,et al.  A gas chromatographic air analyzer fabricated on a silicon wafer , 1979, IEEE Transactions on Electron Devices.

[55]  G. Whitesides,et al.  Fabrication of microfluidic systems in poly(dimethylsiloxane) , 2000, Electrophoresis.

[56]  Peter Vettiger,et al.  High-aspect-ratio, ultrathick, negative-tone near-UV photoresist and its applications for MEMS , 1998 .

[57]  A. Duncan,et al.  Laser microfabricated model surfaces for controlled cell growth. , 2002, Biosensors & bioelectronics.

[58]  I. Mezić,et al.  Chaotic Mixer for Microchannels , 2002, Science.

[59]  Benedetto Allotta,et al.  Micromechatronics in medicine , 1996 .

[60]  Erol C. Harvey,et al.  Patterning, electroplating and removal of SU-8 moulds by excimer laser micromachining , 2001 .

[61]  Guann-Pyng Li,et al.  Characterizing the process of cast molding microfluidic systems , 1999, MOEMS-MEMS.

[62]  Thomas Laurell,et al.  Porous silicon as the carrier matrix in microstructured enzyme reactors yielding high enzyme activities , 1997 .

[63]  Michael G. Olsen,et al.  Passive mixing in microchannels: Fabrication and flow experiments , 2001 .