Deep-UV patterning of commercial grade PMMA for low-cost, large-scale microfluidics

Although PMMA can be exposed using a variety of exposure sources, deep-UV at 254 nm is of interest because it is relatively inexpensive. Additionally, deep-UV sources can be readily scaled to large area exposures. Moreover, this paper will show that depths of over 100µm can be created in commercial grade PMMA using an uncollimated source. These depths are sufficient for creating microfluidic channels. This paper will provide measurements of the dissolution depth of commercial grade PMMA as a function of the exposure dose and etch time, using an IPA:H2O developer. Additionally, experiments were run to characterize the dependence of the dissolution rate on temperature and agitation. The patterned substrates were thermally bonded to blank PMMA pieces to enclose the channels and ports were drilled into the reservoirs. The resulting fluidic systems were then tested for leakage. The work herein presents the patterning, development and system behaviour of a complete microfluidics system based on commercial grade PMMA.

[1]  T. Hubbard,et al.  Two-phase interdigitated microelectrode arrays for electrokinetic transport of microparticles , 2008 .

[2]  M. Parameswaran,et al.  Deep-UV exposure of poly(methyl methacrylate) at 254 nm using low-pressure mercury vapor lamps , 2008 .

[3]  K. Williams,et al.  Deep UV pattern definition in PMMA , 2008 .

[4]  E. Mazur,et al.  Femtosecond laser waveguide micromachining of PMMA films with azoaromatic chromophores. , 2008, Optics express.

[5]  Nam-Trung Nguyen,et al.  Low-pressure, high-temperature thermal bonding of polymeric microfluidic devices and their applications for electrophoretic separation , 2006 .

[6]  J. A. van Kan,et al.  Fabrication of PMMA micro- and nanofluidic channels by proton beam writing: electrokinetic and morphological characterization , 2006 .

[7]  Jürgen Mohr,et al.  Modification of polymethylmethacrylate by deep ultraviolet radiation and bromination for photonic applications , 2006 .

[8]  Aigars Piruska,et al.  The autofluorescence of plastic materials and chips measured under laser irradiation. , 2005, Lab on a chip.

[9]  Tejal A. Desai,et al.  Microfabrication of Multilayer, Asymmetric, Polymeric Devices for Drug Delivery , 2005 .

[10]  D. Joy,et al.  Low Voltage Electron Beam Lithography in PMMA , 2005 .

[11]  Gang Chen,et al.  Low‐Temperature Thermal Bonding of PMMA Microfluidic Chips , 2005 .

[12]  T. Lippert.  Laser application of polymers , 2004 .

[13]  Gary H. Bernstein,et al.  Low temperature development of PMMA for sub-10-nm electron beam lithography , 2003, 2003 Third IEEE Conference on Nanotechnology, 2003. IEEE-NANO 2003..

[14]  Serguei Mikhailov,et al.  Creating sub-surface channels in PMMA with ion beam lithography in only one step , 2003 .

[15]  Pascal Meyer,et al.  Investigations of the development rate of irradiated PMMA Microstructures in deep X-ray lithography , 2002 .

[16]  T. Fujii.  PDMS-based microfluidic devices for biomedical applications , 2002 .

[17]  H. Becker,et al.  Polymer microfluidic devices. , 2002, Talanta.

[18]  Christel Ellstrom,et al.  Integrated Cell Based Assays in Microfabricated Disposable CD Devices , 2000 .

[19]  Ulrich Jagdhold,et al.  DUV and e-beam chemistry of high-sensitivity positive PMMA-based resist , 1999, Advanced Lithography.

[20]  M. Gaitan,et al.  Plastic Microfluid Devices for Clinical Measurements , 1998 .

[21]  Dorian Liepmann,et al.  Key Elements of A Transparent Teflon® Microfluidic System , 1998 .

[22]  S. Soper,et al.  Microcapillary electrophoresis devices fabricated using polymeric substrates and X‐ray lithography , 1998 .

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

[24]  T. Seguchi,et al.  Low temperature gamma-ray irradiation effects on polymer materials—3. Gas evolution and change of molecular weight , 1996 .

[25]  M. Breese,et al.  MeV ion beam lithography of PMMA , 1993 .

[26]  P. Russell,et al.  Low‐voltage electron beam lithography , 1992 .

[27]  Bumkyoo Choi,et al.  Deep X-ray and UV lithographies for micromechanics , 1990, IEEE 4th Technical Digest on Solid-State Sensor and Actuator Workshop.

[28]  J. Moacanin,et al.  Characterization of a dissociative excited state in the solid state: Photochemistry of poly/methyl methacrylate/ - Photochemical processes in polymeric systems. V , 1980 .

[29]  H. Hiraoka,et al.  Radiation chemistry of poly(methacrylates) , 1977 .

[30]  B. Lin.  Deep uv lithography , 1975 .