Abstract
Microreactors and micro-fluidic devices require micro-tube structures to reserve and manipulate extremely small volume of liquid specimen, and nano-hole on the micro-tube is useful for its injection, aspiration and filtration, etc. In the present study, we attempted to develop a precise etching process to form nano-hole to the edge part of the micro glass tube by controlling SiO2 etching conditions with diluted aqueous HF solution. The arrayed micro-glass-tubes were fabricated by electrochemical etching of Si wafer followed by wet-thermal oxidation. The bottoms of arrayed micro-glass-tubes were exposed from Si wafer, which possessed pyramid-shape edges. The etching with optimized concentration of HF formed uniform nano-holes only at every bottom edge, indicating self-alignment of the etching process. The diameter of the nano-holes was controllable in the range of ca. 100-500 nm by adjusting the immersion duration and thickness of the glass tube. Nonlinear diffusion of fluoride species to the bottom edges could be the origin of the self-aligned formation of nano-holes at the bottom edges.
Original language | English |
---|---|
Pages (from-to) | 200-204 |
Number of pages | 5 |
Journal | Electrochimica Acta |
Volume | 53 |
Issue number | 1 |
DOIs | |
Publication status | Published - 2007 Nov 20 |
Keywords
- Arrayed microstructure
- Etching
- Maskless nanofabrication
- Microreactor
- Silicon micromachining
ASJC Scopus subject areas
- Chemical Engineering(all)
- Electrochemistry