Membrane folding to achieve three-dimensional nanostructures: Nanopatterned silicon nitride folded with stressed chromium hinges

Silicon nitride membranes were nanopatterned and then folded into three-dimensional (3D) configurations. The out-of-plane folding was achieved using stressed metal hinges. The concept of folding nanopatterned membranes into 3D shapes is referred to as nanostructured origami because of the similarity to the Japanese paper-art of origami, in which two-dimensional surfaces are folded into volumetric shapes. The stressed metal hinges were modeled analytically and compared to experiment. Experimental results demonstrated controllable folding of nanopatterned silicon nitride membranes.