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SU-8 photoresist is an ideal thermal-imprinting polymer, which has been widely used in micro-nano devices in recent years. However, the research on the filling behavior of SU-8 photoresist during thermal nanoimprinting is not complete. In this paper, the stress relaxation curves and shear stress/rate flow curves were measured to analyze the temperature dependent rheological properties of SU-8 photoresist. The filling behavior of SU-8 photoresist was discussed based on thermal imprinting results at various temperatures. High-precision nanochannels were fabricated with replication error of 2.8% at optimized thermal imprinting temperature of 85[degrees]C and duration of 10 min, which paves the way for high-precision fabrication of SU-8-based micro-nanofluidic chips. KEYWORDS nanotechnology, processing, structure, thermoplastics, viscoelastic properties, viscosity, 1 | INTRODUCTION In recent years, studies on nanofluid system have been reported in fields of DNA detection, [1-5] bio-chemical analysis, [6-8] and medicine. [9-11] Nanochannels are the basic to [...]

Electrohydrodynamic jet (E-jet) printing promises to become a highly efficient and cost-effective high-resolution additive nanomanufacturing technology. However, nanoscale printing of small-molecule solvent inks requires the fabrication of nano nozzles that will accommodate the considerable spreading of the printed droplets. This study documents our steps in developing a fabrication process for nanoscale printing nozzles. First, a silicon nano nozzle mold was fabricated by side-etch lift-off, ultraviolet lithography, and deep reactive ion etching. Then, the nanoscale polymer nozzle was produced by double-casting polydimethylsiloxane and a bonding process. In the application of a polymer nano nozzle for E-jet printing of ethanolic solutions of 1-hexadecanethiol, droplets with a diameter as small as 160 nm were obtained. These results indicate that a polymer nano nozzle can be well adapted to E-jet printing with a fine resolution. [ABSTRACT FROM AUTHOR]

Hot embossing is an emerging technology, which enables cost-effective and high-productivity nanofabrication. It is important to optimize the processing parameters to achieve high replication accuracy nanostructure fabrication. In this article, to reveal the interrelationship between the hot embossing conditions and replication accuracy of two-dimensional (2D) polyethylene terephthalate (PET) nanochannels, the numerical simulations were conducted by using the generalized Maxwell model. The constants of the generalized Maxwell model were calculated by a newly established fitting formula based on experimental compressive creep curves rather than tensile stress relaxation curves. Replication accuracy of 2D PET nanochannels was evaluated by a method based on weighted averages. Orthogonal method was employed during numerical simulations to optimize the hot embossing process. Under optimized hot embossing parameters, 2D PET nanochannels, ~80 nm wide, 250 nm deep and 4 mm long, were precision-imprinted into a PET sheet, INTRODUCTION In recent years, the study of nanofluidic systems has been reported in a wide spectrum of fields such as chemistry, biology, and medicine. The fabrication technique for nanosized components [...]