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CoWoS · Chip-on-Wafer-on-Substrate

TSMC's 2.5D packaging that joins logic die and HBM stacks on a silicon interposer; its wafer capacity gates AI supply.

TSMC advanced-packaging process integrating compute and memory on an interposer; an upstream supply chokepoint.

Also written as: Chip-on-Wafer-on-Substrate

Current numbers

~600 kWRubin Ultra Kyber rack (NVL144) on 800 VDC — GTC 2026 also defined NVL576 as an eight-rack MGX system; supply-chain reports (Apr–Jun 2026) say the package was cut to dual-die 2+2 over CoWoS-L warpage, unconfirmed by NVIDIAas of H2 2027 (announced) · register ↗
~120–140k wafers/monthTSMC CoWoS capacity in 2026, from ~75–80k wafers/month; +50–60k at OSAT partners (TrendForce, June 2026)as of 2026-06 · register ↗
~1.0M wafers2026 CoWoS allocation implied by reported shares: NVIDIA ~60%, Broadcom ~15%, AMD ~11% (May 2026)as of 2026-05 · register ↗

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