Micro/nano functional devices fabricated by additive manufacturing

Micro/nano functional devices featuring deep integration, intelligence, and miniaturization have attracted considerable attention in frontier areas of research, such as micro/nano optics, micro/nano sensors, micro-electromechanical systems, and biomedicine. However, traditional micro/nano fabrication techniques, such as lithography, electrodeposition, etching, and laser microfabrication show inferior capability for manufacturing micro/nano structures with sophisticated geometries and multi-materials. Additive manufacturing (AM) is an advanced manufacturing process that offers great freedom in fabricating highly sophisticated structures over a wide length scale—from nanometers to millimeters. AM technology provides multi-scale, multi-material, and multi-dimensional manufacturing abilities for micro/nano functional devices, greatly advancing their development and applications. In this paper, a comprehensive review of recent advances in the AM of micro/nano functional devices is provided. Functional materials for micro/nano AM are also summarized. Micro/nano AM techniques, as well as fabricated micro/nano functional devices, are highlighted. Finally, limitations of the current investigations are discussed, and a future envision of multiple micro/nano functional devices is proposed. We hope that this review will provide a formwork of micro/nano functional devices fabricated by AM, which could offer a destination board to researchers interested in this area.