3D printing methods for micro- and nanostructures

The physical and physicochemical fundamentals of three-dimensional (3D) micro- and nanoprinting are presented. 3D printing (or additive manufacturing technology) is a process which fabricates structures and devices by depositing material (usually layer by layer) according to a 3D digital model. The methods and results reviewed here are limited to those from micro- and nanoscale fields, which are in demand in the fields of electronics, photonics, and bionics. Special attention is given to methods for fabricating sub-100-nm structures, including single- and two-photon polymerization stereolithography, electrohydrodynamic inkjet printing, and laser-induced forward transfer. The advantages and disadvantages of 3D printing methods are discussed, together with prospects for their development and application.