A Review on Direct‐Write Nanoprinting of Functional 3D Structures with Focused Electron Beams

Abstract Following Moore`s law, the performance of devices should double within a two‐year span, which can either be done by reducing the size of the individual components or adapting the working mechanism. In most cases the same mantra applies – pushing the size while keeping the quality. As manufacturing techniques are approaching the atomic scale, however, miniaturization reaches its intrinsic limit, shifting focus toward higher‐dimensional architectures realized by stacking planar layers or fabricating true, free‐standing nanostructures. A mask‐less, additive manufacturing technique with the capability to produce such 3D structures at the nanoscale is called Focused Electron Beam Induced Deposition (FEBID). Applying a focused electron beam in a conventional scanning electron microscope together with a gaseous metal‐precursor gives access to a vast library of complex, 3D nanostructures, which exhibit feature sizes down to the 10 nm‐range and can be printed in a single step on most substrates. This review aims at introducing the technique to a broader scientific community, breaking down the most important processing routes and highlighting disciplines explored so far ranging from nanooptics and nanomagnetism, over scanning probes and field emitters to sensing and particle trapping. Finally, a future roadmap of the technique is discussed, and prospective research focus identified.