title: Maskless fabrication of nano-fluidic channels by two-photon absorption (TPA) polymerization of SU-8 on glass substrate.
abstract: We present a simple, fast, and repeatable method for fabricating nano-fluidic channels based on two-photon absorption (TPA) polymerization. Since our method does not require any mask, it is relatively cheaper and faster than other conventional lithography techniques. We illustrate that SU-8 has pronounced photoinitiation threshold behavior, which linearly decreases as the repetition rate increases. If the pulse energy and the repetition rate are controlled, channel width can be easily controlled. We report fluidic channels up to 110 nm in width, between polymerized parallel ribs, utilizing TPA and the photoinitiation threshold properties of SU-8. Finally, we also show that high repetition rate laser presents greater controllability in size of the polymerized region by varying fluence.
authors.affiliation: Department of Mechanical Engineering, Ryerson University, 350 Victoria Street, Toronto, Ontario, M3N 2H8, Canada. venkat@ryerson.ca
authors.forename: K
authors.initials: K
authors.lastname: Venkatakrishnan
authors.forename: S
authors.initials: S
authors.lastname: Jariwala
authors.forename: B
authors.initials: B
authors.lastname: Tan
mesh_terms: D004852:Epoxy Compounds / Q000737:chemistry* / Q000528:radiation effects*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D005898:Glass / Q000737:chemistry; D008422:Materials Testing; D046210:Microfluidic Analytical Techniques / Q000295:instrumentation* / Q000379:methods; D049329:Nanostructures / Q000737:chemistry* / Q000528:radiation effects*; D036103:Nanotechnology / Q000295:instrumentation* / Q000379:methods*; D010777:Photochemistry / Q000379:methods; D017785:Photons; D011108:Polymers / Q000737:chemistry* / Q000528:radiation effects*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
chemical_list: D004852:Epoxy Compounds; D011108:Polymers; C520895:SU-8 compound