Figure 2.

a) Schematics showing the curvature of unfoldable 3D microtips controlled by molecular interactions between the precursor and the solid‐mold. b) Predicted and experimental curvatures (r/R) of various solid molds. c–f) Tilted SEM images and cross‐sectional OM images of various architectures: c) cylindrical pillars without trapped airs, μ‐SCs fabricated by d) PDMS mold, e) FOTCS‐treated silicon mold, f) s‐PUA mold. Here, scale bars (white) correspond to 200 µm. g) Dry/wet adhesion strengths for various μ‐SC arrays with 5 different microtips. h,i) Dry/wet adhesion performances for 3 μ‐SCs in different sizes (15, 50, and 500 µm in diameter) with ≈0.93 curvature. j) Detailed unfolding (i) and pulling‐off (ii) processes of a 3D microtip in a microsucker and corresponding images in wet surface. k) Wet‐adhesion profiles for predictions (suction stress, capillary interaction, and total adhesion) and measured data with respect to radius of a void (r_v) between a 3D microtip and a substrate as the adhesive is pulled off. Error bars represent standard deviations (for g–i; N = 10).