Figure 4

Direct drawing of PDMS micropillars on curved substrates. (a) A schematic diagram of the PDMS micropillar drawing from the curved side area of a thin polymer fiber (Drawn not to scale). (b) The bird’s eye-view optical micrograph of three PDMS micropillars drawn on the side of a 1 mm-diameter PTFE fiber. The heights and aspect ratios of A, B, and C are 726 µm, 617 µm, and 510 µm and 35.0, 28.5, and 24.8, respectively. Along the axial direction, they are separated by ~0.8 mm (Scale bar: 500 µm). (c) The side-view of the micropillar array in (b) (Scale bar: 200 µm).