A novel nanochannel fabrication for nanofluidic applications using synchrotron radiation: Via a micro patterned X-ray mask

Micro- and nanofluidic devices are being used increasingly in biological, chemical, and medical applications, and many fabrication methods have been proposed. While micro-sized structures are simply fabricated using standard ultraviolet (UV) lithography processes, there are still limitations in the fabrication of nano-sized structures. This study presents a novel X-ray mask fabrication method for fabricating extremely long nano-sized channels using synchrotron radiation (width and height: ∼200 nm, length: ∼2 cm). The X-ray mask used for manufacturing the nano-sized channels can simply be fabricated by depositing metal on microstructures tilted at a specific angle. The proposed method overcomes the limitations of traditional nanofabrication methods, which are complex, expensive, and time-consuming. Using the fabricated nanochannels, the generation of ion concentration polarization, a novel transport phenomenon in nanofluidics, was investigated. Our novel fabrication method should be a useful tool for various nanofluidic applications due to its various advantages, including simple fabrication process, controllability, and duplicability.