3D nanofabrication by volumetric deposition and controlled shrinkage of patterned scaffolds

Shrinking problems in 3D printing Although a range of materials can now be fabricated using additive manufacturing techniques, these usually involve assembly of a series of stacked layers, which restricts three-dimensional (3D) geometry. Oran et al. developed a method to print a range of materials, including metals and semiconductors, inside a gel scaffold (see the Perspective by Long and Williams). When the hydrogels were dehydrated, they shrunk 10-fold, which pushed the feature sizes down to the nanoscale. Science , this issue p. 1281 ; see also p. 1244