Capacitively Coupled Multichip Modules

This paper introduces a radically new method for interconnecting electronic packages electrically and mechanically. It applies to Levels 0-3 inclusive, including die-to-die (Level 0 - Level 0), die-to- substrate (0-1), substrate-to-substrate (1-1), module-to- module (2-2), and substrate to cable or backplane (1-3). Pulse signals are used to signal among semiconductor wafers, dies, modules, or other ensembles of components Capacitive coupling makes possible extremely dense, low-cost, high-performance interconnections. Uniform electrical interfaces make an integrated package possible, collapsing the traditional packaging hierarchy into a single uniform level. Inherently much lower cost is entailed in the design, test, assembly, and rework of capacitively coupled multichip modules than for conductive modules. Savings accrue from eliminating mechanical connectors, backplane structures, processing equipment & steps, materials, and failure modes of all of these. The requisite equipment already exists in foundries, not just in dedicated MCM houses. Substrates may be thin or thick film, so long as smoothness and planarity match the density and decoupling requirements. For these reasons, any system comprising two or more die where pulse drivers and receivers can be designed in may be a candidate for capacitive coupling.