from step-artefacts (aliasing). Oversampling by a factor of 10 to reduce these artefacts adds another two orders of magnitude 1 PiB per single wafer that has to be transferred in ~1 min to the substrate to achieve high volume manufacturing speeds. Industrial maskless lithography is therefore currently only widely found for structuring lower resolution substrates, like in PCB-panel production, where resolutions ~50µm are most common (at ~2000 times lower throughput demand on the components). Forms Currently, the main forms of maskless lithography are electron beam and optical. In addition, focused ion beam (FIB) systems have established an important niche role in failure analysis and defect repair. Also, systems based on arrays of mechanical and thermally ablative probe tips have been demonstrated. Electron beam (e-beam) The most commonly used form of maskless lithography today is electron beam lithography. Its widespread use is due to the wide range of electron beam systems available accessing an equally wide range of electron beam energies (~10 eV to ~100 keV). This is already being used in wafer-level production at eASIC, which uses conventional direct-write electron beam lithography to customize a single via layer for low-cost production of ASICs. Most maskless lithography systems currently being developed are based on the use of multiple electron beams. The goal is to use the parallel scanning of the beams to speed up the patterning of large areas. However, a fundamental consideration here is to what degree electrons from neighboring beams can disturb one another (from Coulomb repulsion). Since the electrons in parallel beams are traveling equally fast, they will persistently repel one another, while the electron lenses act over only a portion of the electrons' trajectories. Optical Direct laser writing is a very popular form of optical maskless lithography, which offers flexibility, ease of use, and cost effectiveness in R&D processing (small batch production). The underlying technology uses spatial light modulating (SLM) micro-arrays based on glass to block laser pathway from reaching a substrate with a photoresist (in similar manner to digital micromirror devices). This equipment offers rapid patterning at sub-micrometer resolutions, and offers a compromise between performance and cost when working with feature sizes of approximately 200 nm or greater. Direct laser writing for microelectronics packaging, 3D electronics and heterogeneous integration were developed in 1995 at the Microelectronics and Computer Technology Corporation (or MCC) in Austin, Texas. The MCC system was fully integrated with precision control for 3D