Novel nanofluidic chemical cells based on self-assembled solid-state SiO2 nanotubes on silicon- on-insulator (SOI) substrates have been successfully fabricated and tested. The vertical SiO2 nanotubes with a smooth cavity are built from Si nanowires which were epitaxially grown on the SOI surface. The nanotubes have a rigid, dry-oxidized SiO2 wall with precisely controlled nanotube inner diameter, very attractive for chemical-/bio-sensing applications. No dispersion/aligning procedures were involved in the fabrication of nanofluidic devices by using this technology, enabling clean and smooth chemical cell. Ion translocation measurements have been successfully carried out on a SiO2 nanotube channel with 20 nm in diameter. A robust and well-controlled nanotube chemical cell is an excellent case of developing functional nanomaterials by leveraging the strength of top-down lithography and the unique advantage of bottom-up growth. These solid, smooth, clean SiO2 nanotubes and nanofluidic devices are very encouraging and attractive in future bio-medical applications, such as single molecule sensing and DNA sequencing.
Pub Type: Journals