Advanced RF/baseband interconnect schemes for inter- and intra-ULSI communications

Future inter- and intra-ULSI interconnect systems demand extremely high data rates (up to 100 Gbps/pin or 20-Tbps aggregate) as well as bidirectional multiI/O concurrent service, re-configurable computing/processing architecture, and total compatibility with mainstream silicon system-on-chip and system-in-package technologies. In this paper, we review recent advances in interconnect schemes that promise to meet all of the above system requirements. Unlike traditional wired interconnects based solely on time-division multiple access for data transmission, these new interconnect schemes facilitate the use of additional multiple access techniques including code-division multiple access and frequency-division multiple access to greatly increase bandwidth and channel concurrency as well as to reduce channel latency. The physical transmission line is no longer limited to a direct-coupled metal wire. Rather, it can be accomplished via either wired or wireless mediums through capacitor couplers that reduce the baseband noise and dc power consumption while simplifying the fabrication process by eliminating vertical metal studs needed in three-dimensional ICs. These new advances in interconnect schemes would fundamentally alter the paradigm of ULSI data communications and enable the design of next-generation computing/processing systems.