A Novel Additive Manufacturing System for 3D Printed Electronics: Wire-Resin Co-Axial Material Extrusion

Abstract

As interest in a system-level approach to electronics manufacturing grows, processes for independently manufacturing complex circuit designs are gaining more traction. The current processes face multiple challenges, for example, issues such as ink “wash-out” that continue to occur due to higher temperature and pressure in processes such as in-mold electronics. Other processes, such as embedded three-dimensional (EMB3D) printing, require creating a new mold design for every design iteration, which is challenging and time-consuming. Therefore, there is a need for a robust method to rapidly fabricate complex interconnections within the same machine envelope. Presently, there are limited wire-embedding techniques for manufacturing interconnections in a planar build layer. This paper presents a novel wire-embedding technique through a co-axial extrusion process, which can be retrofitted into a generic material extrusion (MEX)-based hybrid additive manufacturing (AM) machine and uses a wire-based feedstock, which is substantially less expensive than conductive inks and requires fewer processing steps than conventional direct ink writing systems. Hybrid AM machines retrofitted with this system can be used to develop capabilities to incorporate functional electronic components within the print volume and can be used in applications such as antennas, strain sensors, neural probes, sensing elements, electrodes, and anti-counterfeiting features, among others. Hybrid AM can potentially automate this process by integrating complementary techniques such as pick-and-place and wire-embedding simultaneously within a single build.