A Shielding Structure for Crosstalk Reduction in Silicon Interposer

High-density interconnects including redistribution layers (RDLs) and through-silicon-vias (TSVs) in silicon interposer require effective crosstalk-reduction signaling schemes. In this letter, a novel ground RDL lines structure utilizing ohmic contact is proposed for coupling mitigation, where the conventional insulator layer between the silicon substrate and the ground RDL lines is removed. An equivalent circuit model is developed to capture the coupling reduction mechanism. The proposed structure is then verified by the full-wave simulations. Finally, a test sample is fabricated and measured. The measurement results show a good correlation with those of the developed equivalent circuit model.