Droplets wetting and evaporating on ethanol-philic micro-structured surfaces

Four hydrophobic micro-structured surfaces and a polished silicon wafer were tested. First, wettability on different surface morphologies was evaluated. Initial and temporal contact angles were measured. Then, the droplet geometry evolution was monitored. Four evaporation stages were identified. Besides, an evaporation critical time (ECT) was defined. The effects of surface morphology and surface temperature on droplet wetting and evaporating were discussed.