Transient Analysis of Through-Silicon Vias in Floating Silicon Substrate

For through-silicon vias (TSVs) in a floating silicon substrate, electric fields from signal TSVs terminate at ground TSVs instead of the substrate. The MOS capacitance of TSVs in a floating silicon substrate is quite different from that of TSVs in a well-grounded silicon substrate. Therefore, it is essential to perform transient analysis of such TSVs to facilitate designs and applications of 2.5-D and 3-D ICs. This paper presents a systematic study of time-domain responses of TSVs in a floating silicon substrate. Impacts of the floating substrate and the temperature are considered and investigated thoroughly. The equivalent circuit models are developed and applied to predict the signal propagation. The crosstalk voltages among TSVs are accurately captured and compared for different oxide charges and temperatures.