Substrate-integrated waveguides in glass interposers with through-package-vias

This paper presents, for the first time, substrate-integrated waveguides (SIWs) in ultra-thin glass with through-package-vias (TPVs). An SIW operating at 20 GHz was designed in bare glass substrates to support the dominant TE10 mode and to avoid exciting TE₂₀ mode. The simulated propagation constant confirmed the proper design for one-mode excitation, while the distributions of electromagnetic fields and surface current were examined and they exhibited similar patterns to those in dielectric-filled rectangular waveguides. Furthermore, the simulated S-parameter shows that the insertion loss at 20 GHz is 0.67 dB/cm, and 100% relative bandwidth was achieved. Finally, the impacts of TPV taper and the variability of the glass thickness and TPV pitch on the electrical performance of the SIW in glass interposers with TPVs were studied and presented.