Hybrid 3D Printing of Molten Metal Microdroplets and Polymers for Prototyping of Printed Circuit Boards Featuring Interdigitated 3D Capacitors

This paper presents layer-by-layer additive manufacturing (AM) of molten metal microdroplets and dielectric materials to fabricate multilayer hybrid circuit boards featuring interdigitated 3D capacitors. The printed metal lines have a low resistance of 5 m Omega/mm, 12 times lower than state-of-the-art conductive inks. Exploiting the advantages of Sn-based oxide as an ideal candidate for Electrical Energy Storage Systems (ESS), we successfully fabricated an out-of-plane capacitor module using a combination of polymer and metal materials. The fabrication process exhibited an exceptional aspect ratio of 16, illustrating the successful incorporation of 20 metal layers in the out-of-plane capacitor module. Q factor obtained for the 3D capacitor was in the range of 66-500. Additionally, a fully automated printing technique was employed to produce a multilayer hybrid electrical printed circuit board (PCB), eliminating the need for post-processing. This streamlined approach presents an efficient and comprehensive solution for the one-stop printing of intricate electrical circuits. (c) 2024 The Authors. IEEJ Transactions on Electrical and Electronic Engineering published by Institute of Electrical Engineer of Japan and Wiley Periodicals LLC.