Fig. 2: Origami induced by capillary forces and residual stress.

a Schematic illustration of the capillary force and examples: b metallic dodecahedra⁴⁰; c reversible actuation microgripper³⁹; d cubic structure with “C-shaped” split-ring resonators (SRRs) patterned on each window⁴³; and e self-folded polyhedral geometries with multilayer patterned structures, along with SEM images⁴¹. f Schematic illustrations of residual stress. g Rolled-up bilayer structures with different turns⁵². h Array of rolled-up nanomembranes⁴⁹. i Ion-beam-induced plastic deformation⁷⁴. j Standing microstage with bending hinges⁸⁸. Images reprinted with permission from: b ref. ⁴⁰ from NAS Publishing; c ref. ³⁹, d ref. ⁴³, e ref. ⁴¹, h ref. ⁴⁹, i ref. ⁷⁴ from Wiley; g ref. ⁵² from ACS; j ref. ⁸⁸ from Elsevier