The fabrication process for the capillary-driven SERS-based microfluidic chip. (a) SiO2 film(2 μm) was grown onto a Si wafer using wet oxidation. (b) Lithography. (c) SiO2 was wet-etched by BHF. (d) Si wafer was dry-etched by DRIE. (e, f) Removal of photoresist and SiO2 mask. (g) Au film (200 nm) was deposited on the pattern.
Yang et al. Nanoscale Research Letters 2014 9:138 doi:10.1186/1556-276X-9-138