Laser-Induced Graphene, Fused Filament Fabrication, and Aerosol Jet Printing for Realizing Conductive Elements of UHF RFID Antennas

In this work, three promising Additive Manufacturing (AM)/3D-printing technologies, able to realize conductive elements, are adopted in the realization of antennas. The selected techniques are Fused Filament Fabrication (FFF), Aerosol Jet Printing (AJP), and Laser-Induced Graphene (LIG), which have been compared by measuring the performance of an ultrahigh (UHF) radiofrequency identification (RFID) tag, specifically designed, and realized for the scope. Results have also been analyzed against to data obtained by a reference sample realized in Aluminum. The FFF tag has been manufactured by extruding the Electrifi conductive filament over an ABS printed substrate, used also for the AJP-made antenna. Conversely, the LIG tag has been produced by laser-burning a Kapton polyimide sheet. All the tested technologies, each one with its pros and cons, allowed to realize working prototypes, even if, as expected, with performance lower than the comparison sample. An electroplating process has been also adopted to increase conductivity, with improvements in the FFF prototype. The obtained results are quite satisfactory. Those related to LIG technology do not yet guarantee performance comparable to the other techniques. Nevertheless, the prospect of creating "green" and cost-effective antennas pushes towards further studies, already underway, which include the study of antenna shapes more suitable for the specific technique as well as process optimizations to increase conductivity.