Step by step
Fabrication proceedure: (a) Si3N4 deposition and photolithography, (b) reactive ion etching (RIE), (c) anisotropic KOH etching to vertically etch Si, (d) local oxidation of silicon, (e) RIE and deep-RIE, (f) dioxide layer deposition for sealing, (g) illustration showing top side view of anisotropic KOH etching, (h) schematic view of microchambers at the end of the nanochannel arrays. (Image credit: University of Tokyo)