Miniaturized and Cost-Effective Programmable 2.5D/3.5D Platforms Enabled by Scalable Embedded Active Bridge Chipset

This paper presents the Embedded Multi-die Active Bridge (EMAB) chip, a programmable bridge for cost-effective 2.5D/3.5D packaging technologies. The EMAB chip features a reconfigurable switch array to establish flexible I/O links for connecting multiple chiplets, forming an EMAB chipset based on user needs. It integrates low-dropout regulators (LDOs) for in-package voltage regulation and supports various transmission interfaces, including checkerboard I/Os (50 Mbps–1 Gbps) and MUX I/Os (up to 8 Gbps). Moreover, multiple EMAB chips can be interconnected in a daisy-chain configuration, enabling easy expansion of the EMAB chipset. Additionally, the EMAB chip eliminates TSVs in silicon interposer-based 2.5D packaging technologies and reduces redistribution layer (RDL) complexity through flexible I/O links established within the EMAB chip. Furthermore, EMAB chip can be pre-manufactured as a precast supporting layer (known good die, KGD), which shortens the product development cycle and enhance integration yield. Overall, the EMAB chip offers a miniaturized, low-cost, fast time-to-market and scalable solution for advanced 2.5D/3.5D packaging.