Figure 1
From: Long-range spontaneous droplet self-propulsion on wettability gradient surfaces
Fabrication process of wettability gradient surface. (a) Oxidation. (b) Patterns fabrication though UV lithography. (c) Silicon oxide etching via RIE. (d) Silicon etching via deep RIE. (e) Removal of photoresist. (f) SEM images of the patterned wettability gradient surface, SiO2 stripe and the silicon nanopillars structures.
