Silicon interposer platform with low-loss through-silicon vias using air

A silicon interposer platform featuring low-loss through-silicon vias (TSVs) using air is proposed and demonstrated. The proposed low-loss TSVs are fabricated by partially etching silicon between the signal and ground TSVs. High-frequency characterization in the 10 MHz-to-20 GHz frequency range demonstrates that the proposed TSVs reduce capacitance by 63.2% at 20 GHz compared to conventional TSVs.