Characterization of Fine Pitch Interconnections (<=10um) on Silicon Interconnect Fabric for Heterogeneous Integration - Siva Jangam

The Silicon-Interconnect Fabric (Si-IF) is a highly scalable platform for heterogenous integration of dielets. We propose a fine-pitch integration scheme where dielets are attached to the Si-IF with fine-pitch interconnects (≤10 µm) at short inter-dielets spacings (≤100 µm) using direct metal-metal Thermal Compression Bonding process (TCB). As a result, short links on Si-IF (≤ 500 µm) are used for inter-dielet communication, reducing the latency to ≤ 35 ps. We experimentally demonstrated the measured insertion loss in these short Si-IF links (≤ 500 µm) is ≤2 dB for frequencies up to 30 GHz. As a result, we show that assemblies on Si-IF have 10-40X lower parasitic inductance, and 7-35X lower parasitic capacitance compared to assemblies on interposers and PCBs. We propose the Simple Universal Parallel intERface for chips (SuperCHIPS) protocol as a physical layer for data transfer that efficiently utilizes the fine pitch Si-IF technology. Using SuperCHIPS protocol, data rates of ≥ 10 Gbps/link are realizable at an energy/bit of ≤0.04 pJ/b. Further, the aggregate bandwidth/mm is ≥ 8 Tbps/mm. This corresponds to an improvement of 120-300X in bandwidth/mm and a reduction of 100-500X in energy/bit compared to conventional systems.