**6. TSV-induced substrate noise in 3D integrated circuits**

Through-Silicon-Via (TSV) is a cylindrical metallic structure that is assumed to be used for power/signal distribution in a three-dimensional (3D) stack of dies. It has dielectric layer around it and normally passes through the Si-substrate in vertical direction. Figure 5 shows the cross section of a Si-Substrate with MOSFET transistor and TSV. Part of the Signal/logic switching transition though TSV can cross-through the barrier layer and may pass through the substrate and impact the performance of neighboring active devices and TSVs, known as TSV induced noise. It depends on TSV to device distance and substrate contacts. The transitions through TSVs may vary the body voltage VB of the MOSFET device. TSVsinduced substrate noise is almost directly related to the density of TSVs.

Fig. 5. Cross-section view of TSV-to-device coupling (Khan, 2009, 2011).

Figure 6 shows variations in the MOSFET device body voltage, VB, for different distances from a TSV for the set of design parameters shown by this Figure. The transitions are very short lived with only 50ps transition time.

Fig. 6. Body voltage during TSV signal transition at different distances, dTSV , for VTSV=1V square wave, hTSV=20um, tliner=1um, dgt=0.5um, signal transition time=50ps (Khan, 2009, 2011).
