Pad Redistribution Chip for Compact Stacked Packages

The patent transitions from planar wire routing (2D horizontal/vertical extension) to three-dimensional vertical stacking with through-silicon vias (TSVs). Electrical connections are established by routing signals vertically through the substrate via TSVs, then redistributing them on the opposite surface. This dimensional change eliminates wire interference while maintaining compact package footprint.

The patent introduces through-silicon vias (TSVs) as intermediary structures to transfer electrical signals between different layers. The TSVs act as vertical conduits that penetrate the substrate, enabling compact inter-layer connections without requiring long horizontal wire traces, thus resolving the contradiction between reliable connections and compact size.

The patent enables multi-chip stacking by implementing vertical signal routing through TSVs. Each chip layer can be independently connected to the substrate below through vertical vias, eliminating the need for horizontal wire routing between stacked chips. This allows higher chip density without increasing wire interference.

The patent segments the electrical connection paths into vertical TSV routes and horizontal redistribution layers. By separating the vertical signal transmission function (handled by TSVs) from the horizontal signal routing function (handled by redistribution traces on chip surfaces), the design enables compact multi-chip stacking while avoiding wire interference.

The patent performs pad redistribution during the wafer fabrication stage using standard semiconductor manufacturing processes. The TSVs and redistribution traces are formed as part of the wafer-level processing before chip dicing, which simplifies subsequent assembly. This preliminary action embeds the redistribution functionality directly into the chip structure, avoiding complex post-assembly modifications.

The patent uses standard semiconductor fabrication techniques (photolithography, etching, deposition, plating) to create the pad redistribution structure. These are universal, well-established processes that can be integrated into existing manufacturing lines, reducing the need for specialized equipment or complex manufacturing steps despite the added functionality.