Growth-Like Swelling of 2D Precursors for Efficient Fabrication of Complex 3D Microstructures

3D microstructures have offered the potential for performance enhancement in nearly every type of microsystem. Although traditional solvent-induced swelling can easily and efficiently fabricate some complex 3D microstructures, their 3D morphology can be maintained only in a solvent environment, which severely limits the applications of these 3D microstructures. Here, we present a fabrication method to induce photocurable monomers into elastomeric microstructures to generate a buckling deformation of the microstructures, which is stable and irreversible after photo-curing. This process is applicable to a variety of elastomeric polymers, photocurable monomers, and solvents. A 4-inch sample of these 3D microstructures can be efficiently fabricated within 5–20 min. Moreover, it is compatible with imprinting processes, thereby further expanding both the material applicability and manufacturing efficiency for 3D microstructures. Meanwhile, a variety of complex 3D microstructures are obtained by controlling the growth-like swelling cycles and the shape of 2D precursors. To demonstrate the enormous potential of this growth-like swelling process, we use this strategy to fabricate octopus-inspired 3D micro-sucker arrays for underwater adhesion.