Impact of On-Chip Interconnect on the Performance of 3-D Integrated Circuits With Through-Silicon Vias: Part II

3-D integration using through-silicon vias (TSVs) can decrease interconnect length and improve chip performance. In this paper, electrical links consisting of TSVs and horizontal wires are designed, fabricated, and measured to analyze TSV capacitance and link delay. Compact models for the capacitance of a TSV surrounded by variable number of ground TSVs are developed and compared with measurements. The impact of TSV placement and scaling on link performance is further analyzed. The results demonstrate that placing TSVs closer to their drivers can effectively improve the performance of 3-D integrated circuit (3-D IC) links. Moreover, link delay is significantly improved by scaling TSV geometry to the point that 3-D IC links become on-chip wire limited.