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3D-printed circuit boards: How they’re
made and why they matter
Once confined mainly to home-brew tinkering, circuit boards created via 3D printing are now practical for some manufactured products. J.F. Brandon • BotFactory Inc.
Example of an nScrypt system extruding conductive traces on a FDM-printed substrate.
In the past ten years 3D Printing has gone om a niche prototyping tool to a process acceptable for mass production. Most of the recent hubbub has been about monolithic plastic and metals. But new materials and processes have appeared to help create 3D-printed PCBs that meet long-standing engineering problems. If the history of electronics manufacturing could be summarized in one phase, it would be, “Shrinking everything to nothing to squeeze out something faster.” The push towards miniaturization has been driven by the inviolable laws of nature – faster devices that consume less power require shorter electrical paths. However, the printed circuit board is an outlier in the electronics world. PCBs still use basic drilling and plating processes perfected 50 years ago. That is not to say that PCB manufacturing is trivial or antiquated. But the investment in new PCB manufacturing methods is a pittance compared to the hundreds of billions put into chip fabs by IC makers such as TMSC and AMD. 52
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It is worth looking at the details of PCBs and their construction. The word ‘printed’ in printed circuit board only describes half of the process – the silkscreen masks are the only part that is printed. A PCB is originally copper foil on a rigid fiberglass laminate which is selectively etched, drilled, and plated using a set of silkscreens and chemical baths to produce the final product. The sole purpose of the PCB is to reliably connect passive and active components and provide a reliable platform for integration or interactions with the rest of a product. For example, the PCB in the average computer keyboard connects electronic elements together, and manages human interactions and provides a sound mechanical connection to DESIGN WORLD
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