AC coupled interconnect for dense 3-D ICs

This paper presents the potential application of AC Coupled Interconnect (ACCI) for dense three-dimensional (3-D) ICs. The concept of inductive ACCT for 3-D stacking ICs has been proposed. Combined with the "through vias" technology, the inductive ACCI can provide small pitch vertical interconnects, as well as an excellent thermal solution for dense 3-D ICs. The transformer modeling and transceiver circuit design have also been investigated. The simulations predict that for 20 μm thinned die stacks coupled by a 100 μm diameter transformer, the transceiver circuit fed with a 5 Gbps input stream consumes 15.6 mW power.