Effect of substrate contacts on reducing crosstalk noise between TSVs

Abstract

We propose a model for coupling that considers substrate contacts between through silicon vias (TSVs) in bulk-CMOS technologies. The proposed model is compact but has reasonable accuracy for the dense substrate contacts in largescale three dimensional integrated circuits (3D ICs). We describe the modeling for substrate contacts with the equivalent electrical circuit, discuss the impact of substrate contacts on the electrical parasitic parameters, and clarify the effect of substrate contacts on reducing crosstalk noise and increasing delay. Results of analysis show that if substrate contacts are not considered, crosstalk noise becomes the overestimate of 5 to 700 times and delay becomes the underestimate of 1.4 to 2.4 times.

Noise coupling between TSVs and active devices: Planar nMOSFETs vs. nFinFETs

“…As shown in Table 3, placing the substrate contact closer to the active devices led to a reduction of the coupling induced current variation to 1.05 % (at 1 GHz) for planar devices and 0.2% (at 1 GHz) for the FinFet case. Depending on the level of allowed current variation, this may have a big impact on the KOZ extraction: if the maximum allowed total current variation for planar devices is 2% at 1 GHz, the KOZ is 28 µm; with the grounded closed substrate contact [7], the KOZ is as small as 8 µm …”