3D printing of functional metal and dielectric composite meta‐atoms

In this report, a novel fabrication method, based on casting Field's metal inside dielectric molds made via fused deposition modeling, is presented. Fused deposition modeling (FDM) has become one of the most common rapid prototyping methods. Whilst it generally produces good quality mechanical structures in thermoplastics, few reliable methods have been demonstrated that produce good quality 3D electrically conductive structures. By using Field's metal to transform dielectric molds into conductive structures, nearly any continuous metal geometry buried within the polymer can be created, allowing for the realization of complex 3D architectures. A wide range of thermoplastic materials used in fused deposition modeling have been investigated, to identify the best candidates in terms of processing temperature, relative permittivity, and loss tangent. Experimental measurements and X-ray computer tomography scans are used to determine the quality of structures fabricated using this method. Based on these findings, functional metamaterials devices operating at 600–700 MHz with high Q-factors have been produced. This method shows potential to be incorporated into standard FDM setups and could be utilized for the fabrication of curved and 3D geometries.