Ultra wideband 3D interconnects using aerosol jet printing up to 110 GHz

In this paper, the authors present proof of concept 3D printed interconnects fabricated using aerosol jet printing (AJP) technology. A trapezoidal structure was 3D printed on Liquid Crystal Polymer (LCP) and Coplanar Waveguides (CPW) were printed on top of them to imitate mm-wave packaging. The printing was done using silver nanoparticle ink that acquired 40% conductivity of the bulk silver after sintering at 200 °C for one hour. Scattering Parameters (S-parameters) were simulated and measured from 1 GHz to 110 GHz. The CPW interconnects yielded insertion loss of as low as 0.49 dB/mm including the trapezoid, and with a loss of 0.38 dB/mm on LCP substrate at 110 GHz. This work represents AJP as a solution for cost-effective system-on-package (SoP)/ millimeter-wave (mm-wave) systems.