Inkjet printed 3D architectures: from silver micropillar arrays and lattices to multimaterial metamaterials

Inkjet printing can offer scalable, on-site manufacturing for a wide variety of functional materials, such as metal nanoparticles and polymers. However, to date inkjet deposition of complex 3D geometries remains challenging limiting its application potential. We report on inkjet printing of highly conductive silver structures with fully 3D architectures, based on self-supporting tilted micropillars. These structures can be printed in large arrays, with a vertical height of several millimetres and strut thickness of 50 μm. To demonstrate their potential, the pillars are arranged into lattices, and spiralling structures. Metamaterial structure is produced consisting of floating silver shapes supported by a polymer matrix, and highly anisotropic dielectric properties are demonstrated at microwave frequencies, which can be easily tailored by the orientation of the silver elements. These results push the boundaries of 3D geometric complexity in inkjet printing, enabling new and improved manufacturing solutions for communication systems, electronics and metamaterials.