Mechanisms, Capabilities, and Applications of High-Resolution Electrohydrodynamic Jet Printing

This review gives an overview of techniques used for high-resolution jet printing that rely on electrohydrodynamically induced flows. Such methods enable the direct, additive patterning of materials with a resolution that can extend below 100 nm to provide unique opportunities not only in scientific studies but also in a range of applications that includes printed electronics, tissue engineering, and photonic and plasmonic devices. Following a brief historical perspective, this review presents descriptions of the underlying processes involved in the formation of liquid cones and jets to establish critical factors in the printing process. Different printing systems that share similar principles are then described, along with key advances that have been made in the last decade. Capabilities in terms of printable materials and levels of resolution are reviewed, with a strong emphasis on areas of potential application. Electrohydrodynamic jet printing is an additive fabrication approach that enables the direct patterning of materials with nanoscale resolution. This approach, which relies on electrohydrodynamically induced flows of liquid inks, presents a strong potential for printed electronics, tissue engineering, and photonic devices. This review summarizes recent progress, ranging from the underlying processes of jet formation and droplet generation to engineering systems for high-speed printing, functional materials for inks, and practically achievable levels of resolution.