Figure 7. 3D images and x−z cross sections of water drops condensing on a LIS composed of hydrophilic rectangular pillars (w, s = 20 μm, h = 10 μm).

Images are recorded after (a) 50 s, (b) 200 s and (c) 260 s, respectively. The drops nucleate and grow preferentially on the pillar top surface. Few drops nucleate on a lubricant surface. In the later stage (c) the drops contact the pillars’ bottom surface. The water drops wet the bottom surface by displacing the lubricant, and the drops do not detach again. Movies of 3D images and x−y and x−z cross sections are available in the supplemental files S3 and S4.