Additive Manufacturing for Nano-Feature Applications: Electrohydrodynamic Printing as a Next-Generation Enabling Technology

Regardless of the technology, additive or subtractive, the miniaturization trend is constantly pushing for smaller resolutions. The rise of global challenges in material availability, fabrication in three dimensions (3D), design flexibility and rapid prototyping have pushed additive manufacturing (AM) into the spotlight. Addressing the miniaturization trend, AM has already successfully answered the challenges for microscale 3D fabrication. However, fabricating nano-resolution still presents a challenge. In this review, we will present some of the most reported AM-based technologies capable of nanoscale 3D fabrication addressing resolutions of ≤ 500 nm. The focus is placed on Electrohydrodynamic (EHD) printing (also known as e-jet printing), as EHD printing seems to have the best trade-off when it comes to technique complexity, achievable resolutions, material diversity and potential to scale-up throughput. An overview of the smallest achieved resolutions as well as the most unique use cases and demonstrated applications will be addressed in this work.