Aerosol Jet Printed, Microwave Microstrip Ring Resonators for System-In-Package Applications

This article presents the design, simulation, and fabrication of printed microstrip transmission line (TL) and microwave ring resonators using aerosol-jet printing for system-in-package applications. The printed TLs are 8 mm long and their S-parameters are measured over a wide bandwidth ranging from 1 to 26 GHz. Their insertion loss ranges between 0.02 dB/mm at 1 GHz and 0.56 dB/mm at 26 GHz. Ring resonators were designed and printed to operate at center frequencies of 15.5, 17.5, 19.5, and 21.5 GHz by tuning the size of the ring. Variability studies are carried out to evaluate the ability of the printing process to fabricate reproducible devices. The coupling gap is optimized in order to minimize the insertion loss in the ring resonators without compromising Q-factor. The simulations show good agreement with the experimental results. The ability to print both conductors as well as dielectrics for the fabrication of microwave resonators demonstrate the potential for in-package integration of RF resonators for low-cost sensor applications.